A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
Chromatographic techniques in which the mobile phase is a liquid.
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
The systematic study of the complete complement of proteins (PROTEOME) of organisms.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
The protein complement of an organism coded for by its genome.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
An extraction method that separates analytes using a solid phase and a liquid phase. It is used for preparative sample cleanup before analysis by CHROMATOGRAPHY and other analytical methods.
Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.
A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.
The identification of selected parameters in newborn infants by various tests, examinations, or other procedures. Screening may be performed by clinical or laboratory measures. A screening test is designed to sort out healthy neonates (INFANT, NEWBORN) from those not well, but the screening test is not intended as a diagnostic device, rather instead as epidemiologic.
A mass-spectrometric technique that is used for microscopic chemical analysis. A beam of primary ions with an energy of 5-20 kiloelectronvolts (keV) bombards a small spot on the surface of the sample under ultra-high vacuum conditions. Positive and negative secondary ions sputtered from the surface are analyzed in a mass spectrometer in regards to their mass-to-charge ratio. Digital imaging can be generated from the secondary ion beams and their intensity can be measured. Ionic images can be correlated with images from light or other microscopy providing useful tools in the study of molecular and drug actions.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.
Copies of DNA sequences which lie adjacent to each other in the same orientation (direct tandem repeats) or in the opposite direction to each other (INVERTED TANDEM REPEATS).
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.
Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.
Concentration or quantity that is derived from the smallest measure that can be detected with reasonable certainty for a given analytical procedure.
Techniques for labeling a substance with a stable or radioactive isotope. It is not used for articles involving labeled substances unless the methods of labeling are substantively discussed. Tracers that may be labeled include chemical substances, cells, or microorganisms.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
A process that includes the determination of AMINO ACID SEQUENCE of a protein (or peptide, oligopeptide or peptide fragment) and the information analysis of the sequence.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Databases containing information about PROTEINS such as AMINO ACID SEQUENCE; PROTEIN CONFORMATION; and other properties.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
Mixtures of many components in inexact proportions, usually natural, such as PLANT EXTRACTS; VENOMS; and MANURE. These are distinguished from DRUG COMBINATIONS which have only a few components in definite proportions.
Methods for assessing flow through a system by injection of a known quantity of an indicator, such as a dye, radionuclide, or chilled liquid, into the system and monitoring its concentration over time at a specific point in the system. (From Dorland, 28th ed)
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.
A research technique to measure solvent exposed regions of molecules that is used to provide insight about PROTEIN CONFORMATION.
Separation of a mixture in successive stages, each stage removing from the mixture some proportion of one of the substances, for example by differential solubility in water-solvent mixtures. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.
A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.
A chromatography technique in which the stationary phase is composed of a non-polar substance with a polar mobile phase, in contrast to normal-phase chromatography in which the stationary phase is a polar substance with a non-polar mobile phase.
The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.
The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.
Techniques for using whole blood samples collected on filter paper for a variety of clinical laboratory tests.
Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)
The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
The systematic identification and quantitation of all the metabolic products of a cell, tissue, organ, or organism under varying conditions. The METABOLOME of a cell or organism is a dynamic collection of metabolites which represent its net response to current conditions.
Compounds in which a methyl group is attached to the cyano moiety.
Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Glycosides of GLUCURONIC ACID formed by the reaction of URIDINE DIPHOSPHATE GLUCURONIC ACID with certain endogenous and exogenous substances. Their formation is important for the detoxification of drugs, steroid excretion and BILIRUBIN metabolism to a more water-soluble compound that can be eliminated in the URINE and BILE.
Sequential operating programs and data which instruct the functioning of a digital computer.
The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.
The development and use of techniques and equipment to study or perform chemical reactions, with small quantities of materials, frequently less than a milligram or a milliliter.
A plant genus of the family RANUNCULACEAE. Members contain a number of diterpenoid alkaloids including: aconitans, hypaconitine, ACONITINE, jesaconitine, ignavine, napelline, and mesaconitine. The common name of Wolfbane is similar to the common name for ARNICA.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
Use of various chemical separation and extraction methods, such as SOLID PHASE EXTRACTION; CHROMATOGRAPHY; and SUPERCRITICAL FLUID EXTRACTION; to prepare samples for analytical measurement of components.
A constituent of STRIATED MUSCLE and LIVER. It is an amino acid derivative and an essential cofactor for fatty acid metabolism.
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
The chemical and physical integrity of a pharmaceutical product.
The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.
Derivatives of phosphatidic acid in which the hydrophobic regions are composed of two fatty acids and a polar alcohol is joined to the C-3 position of glycerol through a phosphodiester bond. They are named according to their polar head groups, such as phosphatidylcholine and phosphatidylethanolamine.
A highly-sensitive (in the picomolar range, which is 10,000-fold more sensitive than conventional electrophoresis) and efficient technique that allows separation of PROTEINS; NUCLEIC ACIDS; and CARBOHYDRATES. (Segen, Dictionary of Modern Medicine, 1992)
The characteristic 3-dimensional shape of a carbohydrate.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The products of chemical reactions that result in the addition of extraneous chemical groups to DNA.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
Drugs and their metabolites which are found in the edible tissues and milk of animals after their medication with specific drugs. This term can also apply to drugs found in adipose tissue of humans after drug treatment.
A technique using antibodies for identifying or quantifying a substance. Usually the substance being studied serves as antigen both in antibody production and in measurement of antibody by the test substance.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
An essential amino acid. It is often added to animal feed.
The sum of the weight of all the atoms in a molecule.
Drugs used by veterinarians in the treatment of animal diseases. The veterinarian's pharmacological armamentarium is the counterpart of drugs treating human diseases, with dosage and administration adjusted to the size, weight, disease, and idiosyncrasies of the species. In the United States most drugs are subject to federal regulations with special reference to the safety of drugs and residues in edible animal products.
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Proteins found in any species of bacterium.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Devices for accelerating charged particles in a spiral path by a constant-frequency alternating electric field. This electric field is synchronized with the movement of the particles in a constant magnetic field.
The process of cleaving a chemical compound by the addition of a molecule of water.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Proteins prepared by recombinant DNA technology.
Organic compounds containing a carbonyl group in the form -CHO.
A territory of Australia consisting of Canberra, the national capital and surrounding land. It lies geographically within NEW SOUTH WALES and was established by law in 1988.
Elements of limited time intervals, contributing to particular results or situations.
A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An examination of chemicals in the blood.
The application of medical knowledge to questions of law.
Derivatives of GLUCURONIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that include the 6-carboxy glucose structure.
An infant during the first month after birth.
Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
Ligand-binding assays that measure protein-protein, protein-small molecule, or protein-nucleic acid interactions using a very large set of capturing molecules, i.e., those attached separately on a solid support, to measure the presence or interaction of target molecules in the sample.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Method for assessing flow through a system by injection of a known quantity of radionuclide into the system and monitoring its concentration over time at a specific point in the system. (From Dorland, 28th ed)
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)
Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.
Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.
Sulfonic acid derivatives that are substituted with an aliphatic hydrocarbon group.
A class of membrane lipids that have a polar head and two nonpolar tails. They are composed of one molecule of the long-chain amino alcohol sphingosine (4-sphingenine) or one of its derivatives, one molecule of a long-chain acid, a polar head alcohol and sometimes phosphoric acid in diester linkage at the polar head group. (Lehninger et al, Principles of Biochemistry, 2nd ed)
A system for verifying and maintaining a desired level of quality in a product or process by careful planning, use of proper equipment, continued inspection, and corrective action as required. (Random House Unabridged Dictionary, 2d ed)
Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.
Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.
An indicator of body density as determined by the relationship of BODY WEIGHT to BODY HEIGHT. BMI=weight (kg)/height squared (m2). BMI correlates with body fat (ADIPOSE TISSUE). Their relationship varies with age and gender. For adults, BMI falls into these categories: below 18.5 (underweight); 18.5-24.9 (normal); 25.0-29.9 (overweight); 30.0 and above (obese). (National Center for Health Statistics, Centers for Disease Control and Prevention)
A component of PHOSPHATIDYLCHOLINES or LECITHINS, in which the two hydroxy groups of GLYCEROL are esterified with fatty acids. (From Stedman, 26th ed) It counteracts the effects of urea on enzymes and other macromolecules.
Established cell cultures that have the potential to propagate indefinitely.
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.
An estrogenic steroid produced by HORSES. It has a total of five double bonds in the A- and B-ring. High concentration of equilenin is found in the URINE of pregnant mares.
Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.
A flavoprotein oxidoreductase that has specificity for medium-chain fatty acids. It forms a complex with ELECTRON TRANSFERRING FLAVOPROTEINS and conveys reducing equivalents to UBIQUINONE.
Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.
Substances which, when ingested, inhaled, or absorbed, or when applied to, injected into, or developed within the body in relatively small amounts may, by their chemical action, cause damage to structure or disturbance of function. (From Dorland, 27th ed)
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
A plant genus of the family FABACEAE. Members contain MANNOSE-BINDING LECTINS and dioclein.
Methods of comparing two or more samples on the same two-dimensional gel electrophoresis gel.
The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.
Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The rate dynamics in chemical or physical systems.
Methods for determining interaction between PROTEINS.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
A cell line derived from cultured tumor cells.
The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight [1.00784; 1.00811]. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas. Hydrogen ions are PROTONS. Besides the common H1 isotope, hydrogen exists as the stable isotope DEUTERIUM and the unstable, radioactive isotope TRITIUM.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Any compound that contains a constituent sugar, in which the hydroxyl group attached to the first carbon is substituted by an alcoholic, phenolic, or other group. They are named specifically for the sugar contained, such as glucoside (glucose), pentoside (pentose), fructoside (fructose), etc. Upon hydrolysis, a sugar and nonsugar component (aglycone) are formed. (From Dorland, 28th ed; From Miall's Dictionary of Chemistry, 5th ed)
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Inborn errors of metabolism characterized by defects in specific lysosomal hydrolases and resulting in intracellular accumulation of unmetabolized substrates.
Stable nitrogen atoms that have the same atomic number as the element nitrogen, but differ in atomic weight. N-15 is a stable nitrogen isotope.
A multistage process that includes the determination of a sequence (protein, carbohydrate, etc.), its fragmentation and analysis, and the interpretation of the resulting sequence information.
Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.
The clear, viscous fluid secreted by the SALIVARY GLANDS and mucous glands of the mouth. It contains MUCINS, water, organic salts, and ptylin.
Simple sugars, carbohydrates which cannot be decomposed by hydrolysis. They are colorless crystalline substances with a sweet taste and have the same general formula CnH2nOn. (From Dorland, 28th ed)
The removal of a soluble component from a liquid mixture by contact with a second liquid, immiscible with the carrier liquid, in which the component is preferentially soluble. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Semisynthetic derivative of ergot (Claviceps purpurea). It has complex effects on serotonergic systems including antagonism at some peripheral serotonin receptors, both agonist and antagonist actions at central nervous system serotonin receptors, and possibly effects on serotonin turnover. It is a potent hallucinogen, but the mechanisms of that effect are not well understood.
A plant genus of the family Ephedraceae, order Ephedrales, class Gnetopsida, division Gnetophyta.
A principle of estimation in which the estimates of a set of parameters in a statistical model are those quantities minimizing the sum of squared differences between the observed values of a dependent variable and the values predicted by the model.
Errors in the metabolism of LIPIDS resulting from inborn genetic MUTATIONS that are heritable.
Metals that constitute group 1(formerly group Ia) of the periodic table. They are the most strongly electropositive of the metals. Note that HYDROGEN is not considered an alkali metal even though it falls under the group 1 heading in the periodic table.
The aggregation of soluble ANTIGENS with ANTIBODIES, alone or with antibody binding factors such as ANTI-ANTIBODIES or STAPHYLOCOCCAL PROTEIN A, into complexes large enough to fall out of solution.
A flavonol glycoside found in many plants, including BUCKWHEAT; TOBACCO; FORSYTHIA; HYDRANGEA; VIOLA, etc. It has been used therapeutically to decrease capillary fragility.
A plant genus of the family FABACEAE. Members contain resins (RESINS, PLANT) and GLUCANS.
Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.
An emulsifying agent produced in the LIVER and secreted into the DUODENUM. Its composition includes BILE ACIDS AND SALTS; CHOLESTEROL; and ELECTROLYTES. It aids DIGESTION of fats in the duodenum.
A separation technique which combines LIQUID CHROMATOGRAPHY and CAPILLARY ELECTROPHORESIS.
Controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision. (From Webster's Collegiate Dictionary, 1993)
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A plant genus of the family Paeoniaceae, order Dilleniales, subclass Dilleniidae, class Magnoliopsida. These perennial herbs are up to 2 m (6') tall. Leaves are alternate and are divided into three lobes, each lobe being further divided into three smaller lobes. The large flowers are symmetrical, bisexual, have 5 sepals, 5 petals (sometimes 10), and many stamens.
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
An NAD-dependent glyceraldehyde-3-phosphate dehydrogenase found in the cytosol of eucaryotes. It catalyses the dehydrogenation and phosphorylation of GLYCERALDEHYDE 3-PHOSPHATE to 3-phospho-D-glyceroyl phosphate, which is an important step in the GLYCOLYSIS pathway.
Methods used to measure the relative activity of a specific enzyme or its concentration in solution. Typically an enzyme substrate is added to a buffer solution containing enzyme and the rate of conversion of substrate to product is measured under controlled conditions. Many classical enzymatic assay methods involve the use of synthetic colorimetric substrates and measuring the reaction rates using a spectrophotometer.
An estrogenic steroid produced by HORSES. It has a total of four double bonds in the A- and B-ring. High concentration of euilin is found in the URINE of pregnant mares.
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
Chemical groups containing the covalent disulfide bonds -S-S-. The sulfur atoms can be bound to inorganic or organic moieties.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.
Disorders affecting amino acid metabolism. The majority of these disorders are inherited and present in the neonatal period with metabolic disturbances (e.g., ACIDOSIS) and neurologic manifestations. They are present at birth, although they may not become symptomatic until later in life.
Enzymes that catalyze the first step in the beta-oxidation of FATTY ACIDS.
Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically.
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.
Complex sets of enzymatic reactions connected to each other via their product and substrate metabolites.
Oligosaccharides containing two monosaccharide units linked by a glycosidic bond.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.
Oligosaccharides containing various types of glycosidic linkages that yield branching or antennae. The number of antennae (such as bi-, tri-, tetra-, or penta-antennary) in the oligosaccharides on the PROTEOGLYCANS; GLYCOPROTEINS; or LIPOPOLYSACCHARIDES contribute to their biological activities, such as receptor binding and metabolism.

Targeted comparative proteomics by liquid chromatography-tandem Fourier ion cyclotron resonance mass spectrometry. (1/5193)

In proteomics, effective methods are needed for identifying the relatively limited subset of proteins displaying significant changes in abundance between two samples. One way to accomplish this task is to target for identification by MS/MS only the "interesting" proteins based on the abundance ratio of isotopically labeled pairs of peptides. We have developed the software and hardware tools for online LC-FTICR MS/MS studies in which a set of initially unidentified peptides from a proteome analysis can be selected for identification based on their distinctive changes in abundance following a "perturbation". We report here the validation of this method using a mixture of standard proteins combined in different ratios after isotopic labeling. We also demonstrate the application of this method to the identification of Shewanella oneidensis peptides/proteins exhibiting differential abundance in suboxic versus aerobic cell cultures.  (+info)

The identification of 3,4-MDMA from its mass equivalent isomers and isobaric substances using fast LC-ESI-MS-MS. (2/5193)

3,4-methylenedioxymethamphetamine (3,4-MDMA, "Ecstacy") and its 17 isomers and isobaric substances are studied using liquid chromatography (LC)-positive electrospray ionization-mass spectrometry (MS). 3,4-MDMA is a controlled substance, whereas in many countries the other studied isobaric compounds are not. A method for confirmation of the presence of 3,4-MDMA in drug seizures is developed and validated. Using single MS, the compounds produce an intense protonated molecule and some characteristic fragments; but tandem MS (MS-MS) is applied to enhance specificity. The MS-MS fragmentation is studied in order to distinguish 3,4-MDMA from the other 17 related compounds. However, the MS-MS spectra of 3,4-MDMA and six related compounds are very similar. Therefore, the LC-MS-MS method is developed for the unambiguous identification of 3,4-MDMA. The use of a monolithic column allows for 5-min gradient runs. This qualitative method is tested with 49 Ecstacy samples seized by the police. All results are congruent with the ones obtained with other methods.  (+info)

Parallel ion parking: improving conversion of parents to first-generation products in electron transfer dissociation. (3/5193)

Electron-transfer dissociation (ETD) in a tandem mass spectrometer is an analytically useful ion/ion reaction technique for deriving polypeptide sequence information, but its utility can be limited by sequential reactions of the products. Sequential reactions lead to neutralization of some products, as well as to signals from products derived from multiple cleavages that can be difficult to interpret. A method of inhibiting sequential ETD fragmentation in a quadrupole ion trap is demonstrated here for the reaction of a triply protonated peptide with nitrobenzene anions. A tailored waveform (in this case, a filtered noise field) is applied during the ion/ion reaction time to accelerate simultaneously first-generation product ions and thereby inhibit their further reaction. This results in a approximately 50% gain in the relative yield of first-generation products and allows for the conversion of more than 90% of the original parent ions into first-generation products. Gains are expected to be even larger when higher charge-state cations are used, as the rates of sequential reaction become closer to the initial reaction rate.  (+info)

Some structural properties of plant serine:glyoxylate aminotransferase? (4/5193)

The structural properties of photorespiratory serine:glyoxylate aminotransferases (SGAT, EC 2.6.1.45) from maize (Zea mays L.) and wheat (Triticum aestivum L.) leaves were examined. By means of molecular sieving on Zorbax SE-250 column and filtration through centrifugal filters it was shown that dimers of wheat enzyme (molecular mass of about 90 kDa) dissociate into component monomers (molecular mass of about 45 kDa) upon decrease in pH value (from 9.1 or 7.0 to 6.5). At pH 9.1 a 50-fold decrease of ionic strength elicited a similar effect. Under the same conditions homodimers of the maize enzyme (molecular mass similar to that of the wheat enzyme) remained stable. Immunoblot analysis with polyclonal antiserum against wheat seedling SGAT on leaf homogenates or highly purified preparations of both enzymes showed that the immunogenic portions of the wheat enzyme are divergent from those of the maize enzyme. The sequence of 136 amino acids of the maize enzyme and 78 amino acids of the wheat enzyme was established by tandem mass spectrometry with time of flight analyzer. The two enzymes likely share similarity in tertiary and quaternary structures as well as high level of hydrophobicity on their molecular surfaces. They likely differ in the mechanism of transport from the site of biosynthesis to peroxisomes as well as in some aspects of secondary structure.  (+info)

Two-dimensional gas-phase separations coupled to mass spectrometry for analysis of complex mixtures. (5/5193)

Ion mobility spectrometry (IMS) has been explored for decades, and its versatility in separation and identification of gas-phase ions is well established. Recently, field asymmetric waveform IMS (FAIMS) has been gaining acceptance in similar applications. Coupled to mass spectrometry (MS), both IMS and FAIMS have shown the potential for broad utility in proteomics and other biological analyses. A major attraction of these separations is extremely high speed, exceeding that of condensed-phase alternatives by orders of magnitude. However, modest separation peak capacities have limited the utility of FAIMS and IMS for analyses of complex mixtures. We report 2-D gas-phase separations that join FAIMS to IMS, in conjunction with high-resolution and accuracy time-of-flight (TOF) MS. Implementation of FAIMS/IMS and IMS/MS interfaces using electrodynamic ion funnels greatly improves sensitivity. Evaluation of FAIMS/IMS/TOF performance for a protein mixture tryptic digest reveals high orthogonality between FAIMS and IMS dimensions and, hence, the benefit of FAIMS filtering prior to IMS/MS. The effective peak capacities in analyses of tryptic peptides are approximately 500 for FAIMS/IMS separations and approximately 10(6) for 3-D FAIMS/IMS/MS, providing a potential platform for ultrahigh-throughput analyses of complex mixtures.  (+info)

Newborn screening of inherited metabolic diseases by tandem mass spectrometry. (6/5193)

Application of TMS technology in newborn screening has resulted in major expansion of disorder panel for metabolic diseases in recent years. This automated, multiplex testing methodology detects multiple analytes from single analysis of one blood spot, which leads to detection of 30-35 disorders of amino acids, organic acids, and fatty acids metabolism. The early identification of persons affected with inborn errors of metabolism has led to unexpected discoveries related to the natural history of the disorder or options for therapy. This article summarized (1) the basic principles of this technology and methodology. (2) Current status of application of this methodology in the United States, European countries and in China. (3) The positive impacts on the public health and advances in medical genetics. Finally (4) Challenges, issues and possible solutions. The purpose of this article aimed at introducing new technology and exploring the possibilities of implementing into developing countries where medical genetics is not developed and foreseeing the possible problems and obstacles.  (+info)

Peptide-phospholipid cross-linking reactions: identification of leucine enkephalin-alka(e)nal-glycerophosphatidylcholine adducts by tandem mass spectrometry. (7/5193)

The covalent interactions between peptides and lipid oxidation products, with formation of Schiff and Michael adducts, are known to occur during free radical oxidative damage. In this study, leucine-enkephalin-glycerophosphatidylcholine alka(e)nal adducts were analyzed by electrospray tandem mass spectrometry (MS/MS). Upon collision-induced dissociation of the Leucine enkephalin-2-(9-oxo-nonanoyl)-1-palmitoyl-3-glycerophosphatidylcholine, an alkanal Schiff adduct observed at m/z 1187.7, the main product ions were attributed to the phosphocholine polar head and loss of the peptide. Also, product ions resulting from characteristic losses of phosphatidylcholines and cleavages of the peptide chain (mainly b-type) were observed. Additional product ions formed by combined peptide and phosphatidylcholine fragmentations were identified. The fragmentation pattern of the leucine enkephalin-alkanal Schiff adduct and the leucine enkephalin-alkenal phosphatidylcholine Schiff and Michael adducts were similar, although the loss of the peptide for the Michael adduct should occur through a distinct mechanism. These fragmentation pathways differ greatly from those described for peptide-lipid Schiff and Michael adducts, in which only peptide chain cleavages are reported, probably due to charge retention in the glycerophosphatidylcholine polar head in peptide-glycerophosphatidylcholine adducts.  (+info)

Cytoskeletal components of an invasion machine--the apical complex of Toxoplasma gondii. (8/5193)

The apical complex of Toxoplasma gondii is widely believed to serve essential functions in both invasion of its host cells (including human cells), and in replication of the parasite. The understanding of apical complex function, the basis for its novel structure, and the mechanism for its motility are greatly impeded by lack of knowledge of its molecular composition. We have partially purified the conoid/apical complex, identified approximately 200 proteins that represent 70% of its cytoskeletal protein components, characterized seven novel proteins, and determined the sequence of recruitment of five of these proteins into the cytoskeleton during cell division. Our results provide new markers for the different subcompartments within the apical complex, and revealed previously unknown cellular compartments, which facilitate our understanding of how the invasion machinery is built. Surprisingly, the extreme apical and extreme basal structures of this highly polarized cell originate in the same location and at the same time very early during parasite replication.  (+info)

TY - JOUR. T1 - Quantification of sunitinib in human plasma by high-performance liquid chromatography-tandem mass spectrometry. AU - Minkin, Patton. AU - Zhao, Ming. AU - Chen, Zhaoyuan. AU - Ouwerkerk, Jan. AU - Gelderblom, Hans. AU - Baker, Sharyn D.. PY - 2008/10/15. Y1 - 2008/10/15. N2 - A rapid, sensitive and specific method was developed and validated using LC/MS/MS for determination of sunitinib in human plasma. Sample preparation involved a liquid-liquid extraction by the addition of 0.2 mL of plasma with 4.0 mL tert-butyl-methyl-ether extraction solution containing 25 ng/mL of the internal standard clozapine. Separation of compounds was achieved on a C18 (50 mm × 2.1 mm i.d., 3.5 μm) analytical column using a mobile phase consisting of acetonitrile/H20 (65:35, v/v) containing 0.1% formic acid and isocratic flow at 0.150 mL/min for 3 min. The analytes were monitored by tandem-mass spectrometry with electrospray positive ionization. Linear calibration curves in human plasma were ...
TY - JOUR. T1 - Determination of methylmalonyl coenzyme A by ultra high-performance liquid chromatography tandem mass spectrometry for measuring propionyl coenzyme A carboxylase activity in patients with propionic acidemia. AU - Gotoh, Kana. AU - Nakajima, Yoko. AU - Tajima, Go. AU - Watanabe, Yoriko. AU - Hotta, Yuji. AU - Kataoka, Tomoya. AU - Kawade, Yoshihiro. AU - Sugiyama, Naruji. AU - Ito, Tetsuya. AU - Kimura, Kazunori. AU - Maeda, Yasuhiro. PY - 2017/3/1. Y1 - 2017/3/1. N2 - Propionic acidemia (PA) is an inherited metabolic disease caused by low activity of propionyl coenzyme A (CoA) carboxylase (PCC), which metabolizes propionyl-CoA into methylmalonyl-CoA. Although many patients with PA have been identified by tandem mass spectrometry since the test was first included in neonatal mass screening in the 1990s, the disease severity varies. Thus, determining the specific level of PCC activity is considered to be helpful to grasp the severity of PA. We developed a new PCC assay method by ...
A quantitative, selective and fast ultra-high performance liquid chromatography tandem mass spectrometry method for the simultaneous analysis of 33 basic drugs in hair (amphetamines, cocaine, opiates, opioids and metabolites)
Florentina Laura Chiriac, Iuliana Paun, Florinela Pirvu, Luoana Florentina Pascu, Marcela Niculescu, Toma Galaon - Liquid Chromatography Tandem Mass Spectrometry Method for Ultra-Trace Analysis of Organic UV Filters in Environmental Water Samples
TY - JOUR. T1 - Online solid phase extraction with liquid chromatography-tandem mass spectrometry for determination of estrogens and glucocorticoids in water. AU - Goh, Shalene Xue Lin. AU - Duarah, Ankur. AU - Zhang, Lifeng. AU - Snyder, Shane A.. AU - Lee, Hian Kee. N1 - Funding Information: This work was supported by the Singapore National Research Foundation under its Environmental & Water Technologies Strategic Research Programme administered by the Environmental & Water Industry Programme Office (EWI) of the Public Utilities Board, Singapore (Grant no. 706-000-016-490/706-000-016-133 ). S.X.L. Goh is grateful for the award of a graduate research scholarship from the EWI. Publisher Copyright: © 2016 Elsevier B.V.. PY - 2016/9/23. Y1 - 2016/9/23. N2 - The present work describes the development of a novel fully automated online solid phase extraction (SPE) coupled with high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) using negative electrospray ionisation (ESI) for ...
TY - JOUR. T1 - Comparison of gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry methods to quantify α-tocopherol and αtocopherolquinone levels in human plasma. AU - Mottier, Pascal. AU - Gremaud, Eric. AU - Guy, Philippe A.. AU - Turesky, Robert J.. PY - 2002/2/1. Y1 - 2002/2/1. N2 - Two mass spectrometric methods were established for the quantitative analyses of α-tocopherol (TH) and its oxidation product α-tocopherolquinone (TQ) in human plasma. Both methods make use of isotopically labeled internal standards of different levels of deuteration (d3-TH and d6-TQ). Plasma (100 μl) was saponified in the presence of a mixture of antioxidants, and then TH and TQ were extracted with hexane. With the GC-MS method, the analytes were first converted into O-trimethylsilyl derivatives before analysis in the selective ion monitoring mode. The derivatization procedure led to the quantitative conversion of TQ into the O-trimethylsilyl derivative of ...
A novel liquid chromatography-tandem mass spectrometry method is described for the quantitative determination of the endogenous CYP 3A4/5 marker 4β-hydroxycholesterol in human K(2)-EDTA plasma. It is based on alkaline hydrolysis to convert esterified to free 4β-hydroxycholesterol, followed by analyt …
A stereoselective, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the determination of R-acenocoumarol and S-acenocoumarol in human plasma was developed and validated at IPRC bioanalytical labs. The procedure involved solid phase extraction of both enantiomers and their corresponding internal standard. The chromatographic separation was accomplished employing a chiral column and proper mobile phase. Detection was carried out using Waters Micromass® Quattro Premier mass spectrometer in multiple reaction monitoring (MRM) mode using turbo ion spray with negative ionization. The method was validated over a linear range of 0.40 - 40.00 ng/ml for R-acenocoumarol and 0.20 - 20.00 ng/ml for the S-acenocoumarol. Method validation covered different parameters such as linearity, accuracy, precision and stability. The method was successfully applied for the determination of R and S-acenocoumarol in plasma samples of 28 healthy subjects who participated in a pharmacokinetics
Abstract: A liquid chromatography tandem mass spectrometry method was developed for quantifying ten cannabinoids in oral fluid (OF). This method utilizes OF collected by the Quantisal device and concurrently quantifies cannabinol (CBN), cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-THC (11-OH-THC), 11-nor-9-carboxy-Δ9-THC (THC-COOH), 11-nor-9-carboxy-Δ9-THC glucuronide (THC-COOH-gluc), Δ9-THC glucuronide (THC-gluc), cannabigerol (CBG), tetrahydrocannabiverin (THCV), and Δ9-tetrahydrocannabinolic acid A (THCA-A). Solid phase extraction was optimized using Oasis Prime HLB 30 mg 96-well plates. Cannabinoids were separated by liquid chromatography over a BEH C18 column and detected by a Waters TQ-S micro tandem mass spectrometer. The lower limits of quantification (LLOQ) were 0.4 ng/mL for CBN, CBD, THC, 11-OH-THC, THC-gluc, and THCV; and 1.0 ng/mL for THC-COOH, THC-COOH-gluc, CBG and THCA-A. Linear ranges extended to 2000 ng/mL for THC and 200 ng/mL for all other analytes. ...
RATIONALE Neonicotinoids (NNIs) are the fastest expanding group of pesticides in the world over the last two decades; however, they may be a significant contributing factor to bee mortality. The widespread use of NNIs makes it critical to monitor their residuals in the environment. Published methods for NNI analysis are mainly focused on agricultural and food products, and many of them only measured a portion of the commercially available NNIs. METHODS Utilizing a biphenyl stationary-phase column, a sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed to determine eight NNIs, including acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitempyram, thiacloprid and thiamethoxam in environmental water. Two multiple reaction monitoring (MRM) transitions were monitored for each compound to ascertain true positive identification. Isotope-labelled NNIs, d3-acetamiprid, d3-clothianidin, d4-imidacloprid and d3-thiamethoxam, were used to compensate for
An improved method for determining levels of levosulpiride in human plasma using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated. The protein precipitation method was used for plasma sample preparation. Levosulpiride and an internal standard (IS) were isocratically separated on a UPLC BEN C(18) column with a mobile phase of ammonium formate buffer (1 mM, adjusted to pH 3 with formic acid) and acetonitrile (60:40, v/v). MS/MS detection was performed by monitoring the parent -, daughter pair of levosulpiride and the IS at m/z 342 -, 112 and 329 -, 256, respectively. The method was linear from 2.5 to 200 ng/mL and exhibited acceptable precision and percent recovery. The method was successfully demonstrated in pharmacokinetic and bioequivalence studies of two levosulpiride oral formulations administered to healthy volunteers. When compared to the previous LC-MS methods, the proposed method is faster, well-validated, and uses lesser plasma ...
TY - JOUR. T1 - Validation of a high throughput method for serum/plasma testosterone using liquid chromatography tandem mass spectrometry (LC-MS/MS). AU - Singh, Ravinder Jit. PY - 2008/12/12. Y1 - 2008/12/12. N2 - Testosterone, the major androgenic hormone in humans, is commonly measured to aid in the diagnosis of clinical conditions related to its excess or deficiency. In addition, testosterone measurements are used to monitor testosterone replacement-, or antiandrogen therapy. Most commonly, automated direct immunoassays have been used to measure testosterone in human serum. Their advantage compared with other methodologies, lies in high- and rapid sample throughput with minimal human intervention. However, many automated testosterone immunoassays suffer from poor accuracy at the low concentration levels (,50 ng/dL) seen in women and children, or in men undergoing anti-androgen therapy. Our objective was to develop a LC-MS/MS method which measures testosterone in human serum while fulfilling ...
The obligate intracellular lifestyle of Plasmodium falciparum and the difficulties in obtaining sufficient amounts of biological material have hampered the study of specific metabolic pathways in the malaria parasite. Thus, for example, the pools of sugar nucleotides required to fuel glycosylation reactions have never been studied in-depth in well-synchronized asexual parasites or in other stages of its life cycle. These metabolites are of critical importance, especially considering the renewed interest in the presence of N-, O-, and other glycans in key parasite proteins. In this work, we adapted a liquid chromatography tandem mass spectrometry (LC-MS/MS) method based on the use of porous graphitic carbon (PGC) columns and MS-friendly solvents to quantify sugar nucleotides in the malaria parasite. We report the thorough quantification of the pools of these metabolites throughout the intraerythrocytic cycle of P. falciparum The sensitivity of the method enabled, for the first time, the targeted ...
TY - JOUR. T1 - Analysis of metribuzin and its metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry. AU - Kai, Shigemi. AU - Akaboshi, Takeshi. AU - Waki, Masumi. AU - Fuzimaki, Teruhisa. AU - Kanazawa, Hideko. PY - 2011/2. Y1 - 2011/2. N2 - A method for simultaneous determination of metribuzin (MET) and three metribuzin metabolites in livestock products and seafoods by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. MET and its metabolites were extracted from a sample with acetonitrile, followed by InertSepC18 and BondElut SAX cartridge cleanup. The LC separation was performed on a C18 column using 0.01 mol/L ammonium formate-acetonitrile-methanol (70 : 21 : 9) as the mobile phase and MS detection with both positive and negative ion electrospray ionization. The mean recoveries from 10 livestock products and seafoods were generally ,60%, and the relative standard deviations were ,20%.. AB - A method for simultaneous ...
Liquid chromatography tandem mass spectrometry is one of the most specific techniques available in clinical laboratories. In the past, immunoassays were the primary methodology for analysis of steroids in biological samples because they are rapid and easy to perform. However, these methods were shown to suffer from the lack of specificity for measuring many of the diagnostically important steroids. LC-MS/MS overcomes many of the limitations of immunoassays, enhances diagnostic utility of the testing, and expands diagnostic capabilities in endocrinology. In addition to the superior quality of the measurements, LC-MS/MS allows high throughput testing using small sample volume with minimal sample preparation, and frees the laboratory from dependence on suppliers of assay specific reagents. LC-MS/MS is being widely employed for routine measurement of steroids, and the methodology plays an important role in the standardization and harmonization of measurements among clinical laboratories.. ...
Peptide identification is an important problem in proteomics. One of the most popular scoring schemes for peptide identification is X-Corr (cross-correlation). Since calculating X-Corr is computationally intensive, a lot of efforts have been made to develop fast X-Corr engines. However, the existing X-Corr engines are not suitable for high-resolution MS/MS spectrometry because they are either slow or require a specific type of CPU. We present a portable high-speed X-Corr engine for high-resolution tandem mass spectrometry by developing a novel algorithm for calculating X-Corr. The algorithm enables X-Corr calculation 1.25-49 times faster than previous algorithms for 0.01 Da fragment tolerance. Furthermore, our engine is easily portable to any machine with different types of CPU because it is developed in C language. Hence, our X-Corr engine will expedite peptide identification by high-resolution tandem mass spectrometry ...
A highly sensitive and selective liquid chromatography-mass spectrometry (LC-MS) method has been developed for the determination of epirubicin in serum and c...
Busulfan is an alkylating agent widely used in the ablation of bone marrow cells before hematopoietic stem cell transplant. Due to large intraindividual and interindividual variations, and narrow therapeutic window, therapeutic drug monitoring of busulfan is warranted. A quick and reliable HPLC-MS/MS method was developed for the assay of plasma busulfan. HPLC involved C18 column, and MS/MS was used in electrospray ionization (ESI) positive mode. Quantitation and identification of busulfan was made using various multiple reactions monitoring (MRMs). Isotopic labeled busulfan-d8 was used as the internal standard. The method is linear from 50 to 2500 ng/mL and has with-in run and between-run imprecision of |10|%.
TY - JOUR. T1 - Reference ranges for testosterone in men generated using liquid chromatography tandem mass spectrometry in a community-based sample of healthy nonobese young men in the framingham heart study and applied to three geographically distinct cohorts. AU - Bhasin, Shalender. AU - Pencina, Michael. AU - Jasuja, Guneet Kaur. AU - Travison, Thomas G.. AU - Coviello, Andrea. AU - Orwoll, Eric. AU - Wang, Patty Y.. AU - Nielson, Carrie. AU - Wu, Frederick. AU - Tajar, Abdelouahid. AU - Labrie, Fernand. AU - Vesper, Hubert. AU - Zhang, Anqi. AU - Ulloor, Jagadish. AU - Singh, Ravinder. AU - DAgostino, Ralph. AU - Vasan, Ramachandran S.. PY - 2011/8/1. Y1 - 2011/8/1. N2 - Context: Reference ranges are essential for partitioning testosterone levels into low or normal and making the diagnosis of androgen deficiency. We established reference ranges for total testosterone (TT) and free testosterone (FT) in a community-based sample of men. Methods: TT was measured using liquid chromatography ...
BACKGROUND: Oral fluid is an alternative matrix with potential applications in road-side drug screening, work-place testing, drug treatment programs, and epidemiological surveys. Development of methods for extensive drug screening in oral fluid is warranted. METHODS: We developed a liquid chromatography- tandem mass spectrometry (LC-MS/MS) method for drug screening of preserved oral fluid collected with the Intercept collection device. Samples were prepared by liquid-liquid extraction with ethylacetate/heptane (4:1). LC-separation was achieved with an Atlantis dC18-column (2.1 x 50 mm, 3 microm particle). Mass detection was performed by positive ion mode electrospray LC-MS/MS and included the following drugs/metabolites: morphine, 6-monoacetylmorphine, codeine, buprenorphine, methadone, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxyethylamphetamine, cocaine, benzoylecgonine, Delta-9-tetrahydrocannabinol, lysergic acid ...
TY - JOUR. T1 - Asymmetric dimethylarginine predicts survival in the elderly. AU - Pizzarelli, Francesco. AU - Maas, Renke. AU - Dattolo, Pietro. AU - Tripepi, Giovanni. AU - Michelassi, Stefano. AU - DArrigo, Graziella. AU - Mieth, Maren. AU - Bandinelli, Stefania. AU - Ferrucci, Luigi. AU - Zoccali, Carmine. PY - 2013/12. Y1 - 2013/12. N2 - Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase implicated in several age-related biological mechanisms such as telomere shortening and cell senescence. We tested the hypothesis that ADMA blood level is an independent predictor of mortality in elderly. This is a longitudinal population-based cohort study. Participants are a representative cohort of 1,025 men and women (age range 65-102 years) living in Chianti area, Tuscany, Italy. The plasma ADMA was measured by liquid chromatography- tandem mass spectrometry. During the follow-up (95±32 months), 384 individuals died, of whom 141 (37 %) died of cardiovascular (CV) ...
SICHILONGO, Kwenga F.; MUCKOYA, Vallerie A. y NINDI, Mathew M.. A rapid and sensitive LC-MS/MS method for the determination of multi-class residues of antibiotics in chicken liver. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp.01-06. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a1.. A very sensitive, simple and cost-effective liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the determination of multi-class antibiotics in chicken liver was developed. The drugs under consideration were sulfaguanidine and sulfamethazole, trimethoprim, tetracycline, chlortetracycline and tylosin. Linear calibrations were established for all the analytes and the R2 values ranged between 0.9990 and 0.9997. The limits of quantitation (LOQs) varied between 0.025 and 78.8 μg kg-1. The limit of detections (LODs) were better than those that have been reported for the same antibiotics in many instances in other studies and ranged between 0.010-31.5 μg kg-1 with the ...
SICHILONGO, Kwenga F.; MUCKOYA, Vallerie A. e NINDI, Mathew M.. A rapid and sensitive LC-MS/MS method for the determination of multi-class residues of antibiotics in chicken liver. S.Afr.j.chem. (Online) [online]. 2015, vol.68, pp.01-06. ISSN 1996-840X. http://dx.doi.org/10.17159/0379-4350/2015/v68a1.. A very sensitive, simple and cost-effective liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method for the determination of multi-class antibiotics in chicken liver was developed. The drugs under consideration were sulfaguanidine and sulfamethazole, trimethoprim, tetracycline, chlortetracycline and tylosin. Linear calibrations were established for all the analytes and the R2 values ranged between 0.9990 and 0.9997. The limits of quantitation (LOQs) varied between 0.025 and 78.8 μg kg-1. The limit of detections (LODs) were better than those that have been reported for the same antibiotics in many instances in other studies and ranged between 0.010-31.5 μg kg-1 with the ...
An original liquid chromatography-tandem mass spectrometry (LC-MS-MS) method coupled to online extraction has been developed for cyanide determination in blood. A method involving fluorimetric detection after naphthalene-2,3-dicarboxyaldehyde (NDA) complexation by taurine in the presence of cyanide was previously described. Its performance was limited because of the absence of an internal standard (IS). Using cyanide isotope 13C15N as IS allowed quantification in MS-MS. After the addition of 13C15N, 25 µL of blood were diluted in water and deproteinized with methanol. Following derivatization with NDA and taurine for 10 min at 4°C, 100 µL was injected into the online LC-MS-MS system. An Oasis HLB was used as an extraction column, and a C18 Atlantis was the analytical column. The chromatographic cycle was performed with an ammonium formate (20 mM, pH 2.8) (solvent A) and acetonitrile/solvent A (90:10, v/v) gradient in 6 min. Detection was performed in negative electrospray ionization mode ...
Disease-specific compounds (biomarkers) are analyzed in clinical laboratories to assist with diagnosing diseases. This thesis describes development and validation of liquid chromatography tandem mass spectrometry (LC-MS/MS) based tests for diagnosing a diverse group of endocrine and metabolic diseases. The analytical methods used on-line and off-line sample extraction and analytical derivatization as means of enhancing the analytical sensitivity, specificity and clinical utility. All developed methods were extensively validated and reference intervals for the biomarker concentrations were established in blood samples of healthy adults and children. Advantages of the LC-MS/MS as an analytical technique include possibility of simultaneous measurement of multiple analytes and ability of confirming their identity. In this thesis we proposed and evaluated approaches for the assessment of the specificity of analysis in the methods that use tandem mass spectrometry detection. To enhance throughput of ...
La presente simulazione è stata realizzata sulla base delle specifiche raccolte sul tavolo ER del Focus Group IRIS coordinato dallUniversità di Modena e Reggio Emilia e delle regole riportate nel DM 598/2018 e allegata Tabella A. Cineca, lUniversità di Modena e Reggio Emilia e il Focus Group IRIS non si assumono alcuna responsabilità in merito alluso che il diretto interessato o terzi faranno della simulazione. Si specifica inoltre che la simulazione contiene calcoli effettuati con dati e algoritmi di pubblico dominio e deve quindi essere considerata come un mero ausilio al calcolo svolgibile manualmente o con strumenti equivalenti ...
High throughput online solid phase extraction-ultra high performance liquid chromatography-tandem mass spectrometry method for polyfluoroalkyl phosphate esters, perfluoroalkyl phosphonates, and other perfluoroalkyl substances in human serum, plasma, and whole ...
In forensic investigations, such as drug-facilitated crimes, reference values are useful for interpretation of hair results. The aim of this study was to establish levels of zopiclone and two main metabolites, N-desmethylzopiclone and zopiclone N-oxide, in hair after the administration of a single dose of zopiclone, as very limited data are published. A controlled study was performed, where 16 volunteers consumed either 5 or 10mg zopiclone. Hair was sampled prior to consumption and 14, 30, 60, and 120 days after intake. The deposition of drug in hair segments of all sampling time points was followed in small hair segments of 5-mm, using a validated ultra-high performance liquid chromatography-tandem mass spectrometry method. In all participants, hair segments corresponding to the time of intake were positive for zopiclone, but also with lower concentrations in the neighbouring segments. The highest zopiclone concentrations were detected in samples collected 30 or 60 days after intake. For all ...
TY - JOUR. T1 - Effect of ionization modifiers on the simultaneous analysis of all classes of phospholipids by nanoflow liquid chromatography/tandem mass spectrometry in negative ion mode. AU - Bang, Dae Young. AU - Lim, Sangsoo. AU - Moon, Myeong Hee. N1 - Funding Information: This study was supported by the National Research Foundation (NRF) of Korea grant (No. 2011-0016438 ) funded by the Korean government (MEST) and in part by a grant (No. 2011-0001125 ). PY - 2012/6/1. Y1 - 2012/6/1. N2 - The effect of ionization modifiers added to the mobile phase of nanoflow liquid chromatography-tandem mass spectrometry (nLC-ESI-MS 3) on the simultaneous analysis of all phospholipid (PL) classes in negative ion mode has been investigated. While MS analysis of most PL classes is carried out in negative ion mode, analysis of neutral polar (polar but electrically neutral) lipids like phosphatidylcholine (PC) and sphingomyelin (SM) is highly efficient in positive ion mode. Therefore, analysis of PL mixture ...
Charlène Pouech, Florent Lafay, Laure Wiest, Robert Baudot, Didier Léonard, et al.. Monitoring the extraction of additives and additive degradation products from polymer packaging into solutions by multi-residue method including solid phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry analysis. Analytical and Bioanalytical Chemistry, Springer Verlag, 2014, 406 (5), pp.1493-1507. 〈10.1007/s00216-013-7551-4〉. 〈hal-00924245〉 ...
TY - JOUR. T1 - Performance metrics for liquid chromatography-tandem mass spectrometry systems in proteomics analyses. AU - Rudnick, Paul A.. AU - Clauser, Karl R.. AU - Kilpatrick, Lisa E.. AU - Tchekhovskoi, Dmitrii V.. AU - Neta, Pedatsur. AU - Blonder, Nikša. AU - Billheimer, Dean D.. AU - Blackman, Ronald K.. AU - Bunk, David M.. AU - Cardasis, Helene L.. AU - Ham, Amy Joan L.. AU - Jaffe, Jacob D.. AU - Kinsinger, Christopher R.. AU - Mesri, Mehdi. AU - Neubert, Thomas A.. AU - Schilling, Birgit. AU - Tabb, David L.. AU - Tegeler, Tony J.. AU - Vega-Montoto, Lorenzo. AU - Variyath, Asokan Mulayath. AU - Wang, Mu. AU - Wang, Pei. AU - Whiteaker, Jeffrey R.. AU - Zimmerman, Lisa J.. AU - Carr, Steven A.. AU - Fisher, Susan J.. AU - Gibson, Bradford W.. AU - Paulovich, Amanda G.. AU - Regnier, Fred E.. AU - Rodriguez, Henry. AU - Spiegelman, Cliff. AU - Tempst, Paul. AU - Liebler, Daniel C.. AU - Stein, Stephen E.. PY - 2010/2. Y1 - 2010/2. N2 - A major unmet need in LC-MS/MS-based ...
Sigma-Aldrich offers abstracts and full-text articles by [Gabriela Peste, Nela Bibire, Mihai Apostu, Aurel Vlase, Corneliu Oniscu].
Adequate vitamin D status is necessary throughout life in terms of maintaining bone strength, calcium and phosphorus balance, as well as prevention of rickets in children and osteomalacia in adults. The accepted biomarker used for the assessment of vitamin D status is circulating total 25-hydroxyvitamin D (25(OH)D) concentration, which is comprised of the sum of 25-hydroxyvitamin D3 (25(OH)D3) and 25-hydroxvitamin D2 (25(OH)D2) The use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the analysis of total 25(OH)D has also enabled the detection of low concentration, minor vitamin D metabolites in serum. The aims of this work were to examine the impact of three such minor vitamin D metabolites, 25(OH)D2, 24,25-dihydroxyvitamin D (24,25(OH)2D), and 3 epimer of 25(OH)D3 (3-epi-25(OH)D3) on the assessment of vitamin D nutritional status and also to provide further insight and refinement of our understanding of the vitamin D metabolic pathway. This required the development and ...
Steuer, Andrea E; Poetzsch, Michael; Stock, Lorena; Eisenbeiss, Lisa; Schmid, Yasmin; Liechti, Matthias E; Kraemer, Thomas (2017). Development and validation of an ultra-fast and sensitive microflow liquid chromatography-tandem mass spectrometry (MFLC-MS/MS) method for quantification of LSD and its metabolites in plasma and application to a controlled LSD administration study in huma. Drug Testing and Analysis, 9(5):788-797. ...
Detection Of Biomarkers in Cerebrospinal Fluid of Multiple Sclerosis Patients By Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS ...
University of Leicester researchers writing in the journal Chemical Research in Toxicology say they have found convincing evidence that cannabis smoke damages DNA and it could potentially increase the risk of cancer development in humans.Using a newly developed highly sensitive liquid chromatography-tandem mass spectrometry method, the University
Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) has become one of the most used tools in mass spectrometry based proteomics. Various algorithms have since been developed to automate the process for modern high-throughput LC-MS/MS experiments. A probability based statistical scoring model for assessing peptide and protein matches in tandem MS database search was derived. The statistical scores in the model represent the probability that a peptide match is a random occurrence based on the number or the total abundance of matched product ions in the experimental spectrum. The model also calculates probability based scores to assess protein matches. Thus the protein scores in the model reflect the significance of protein matches and can be used to differentiate true from random protein matches. The model is sensitive to high mass accuracy and implicitly takes mass accuracy into account during scoring. High mass accuracy will not only reduce false positives, but also improves the
Lipids are ubiquitous and serve numerous biological functions; thus lipids have been shown to have great potential as candidates for elucidating biomarkers and pathway perturbations associated with disease. Methods expanding coverage of the lipidome increase the likelihood of biomarker discovery and could lead to more comprehensive understanding of disease etiology. We introduce LipidMatch, an R-based tool for lipid identification for liquid chromatography tandem mass spectrometry workflows. LipidMatch currently has over 250,000 lipid species spanning 56 lipid types contained in in silico fragmentation libraries. Unique fragmentation libraries, compared to other open source software, include oxidized lipids, bile acids, sphingosines, and previously uncharacterized adducts, including ammoniated cardiolipins. LipidMatch uses rule-based identification. For each lipid type, the user can select which fragments must be observed for identification. Rule-based identification allows for correct annotation of
Grape pomace extract (GPE) is a rich and relatively low-cost source of phenolic compounds. However, little is known about the main GPE metabolites in mammals, which could help explain the observed health-promoting effects. This study investigated the presence of parent compounds from flavanol, flavonol and stilbene families and their metabolites in rat plasma and tissues after an acute intake of GPE in doses of 300 and 600 mg kg/body weight. The measurement of free compounds and their metabolites was performed by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results showed the presence of epicatechin, epicatechin methyl-glucuronide, epicatechin methyl-sulphate, catechin, catechin-glucuronide, quercetin methyl-glucuronide, resveratrol-3-glucuronide, resveratrol-4-glucuronide and resveratrol-3-sulphate in plasma, which was dose dependent. The most abundant measured compound in plasma was epicatechin-glucuronide. The presence of glucuronidated and ...
Liquid Chromatography / Tandem Mass Spectrometry (LS/MS/MS). Liquid chromatography/tandem mass spectrometry provides identification of analytes of interest within a mixture based on retention time and characteristic parent/daughter ion fragmentation patterns, which provides the compounds unique molecular fingerprint. When liquid chromatography is suitable for separation of compounds, LC/MS/MS can provide significantly greater sensitivity than the corresponding gas chromatography/mass spectrometry (i.e., GC/MS). KorvaLabs employs LC/MS/MS for the identification of substances in white powders - such as in the case of certification of dietary supplements - and for certain compounds in urine where GC/MS is not sufficient.. Gas Chromatography / Mass Spectrometry (GC/MS). Like LC/MS, the related gas chromatography/mass spectrometry (i.e., GC/MS)provides identification based on retention time and ion fragmentation patterns; however, GC/MS… KorvaLabs uses GC/MS for the detection of most banned ...
In early 2011, a food sample of pink colored sugar coated sesame seed from Pakistan was sent to the lab for color determination. The paper chromatography method could not determine any dyes. (As found out later, the unknown pink dye was not an acid dye.) From research it was found that Rhodamine B was a pink water soluble basic dye commonly used as a food adulterant. A standard was ordered and then a qualitative high performance Liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) method was developed (Waters UPLC Aquity w/Waters Premier XE triple quadrapole) to determine Rhodamine B. After utilizing this new method, Rhodamine B was found in the sugar coated sesame seed.. Rhodamine B is an industrial dye and is not allowed in food anywhere in the world. Industrial dyes are not allowed in food because they are toxic; in fact, some industrial dyes are used for suicide.2,3,4 In addition, industrial dyes are not made to food grade specifications with regard to dye purity, heavy metal (i.e., ...
Abstract To support therapeutic drug monitoring of patients with cancer, a fast and accurate method for simultaneous quantification of the registered anticancer drugs afatinib, axitinib, ceritinib, crizotinib, dabrafenib, enzalutamide, regorafenib and trametinib in human plasma using liquid chromatography tandem mass spectrometry was developed and...
Environmental phenols are a group of chemicals with widespread uses in consumer and personal care products, food and beverage processing, and in pesticides. We assessed exposure to benzophenone-3, bisphenol A (BPA), triclosan, methyl- and propyl parabens, and 2,4- and 2,5-dichlorophenol or their precursors in 506 pregnant women enrolled in the National Childrens Study (NCS) Vanguard Study. We measured the urinary concentrations of the target phenols by using online solid-phase extraction-isotope dilution high performance liquid chromatography-tandem mass spectrometry. NCS women results were compared to those of 524 similar-aged women in the National Health and Nutrition Examination Survey (NHANES) 2009-2010, and to 174 pregnant women in NHANES 2005-2010. In the NCS women, we found significant racial/ethnic differences ( ...
Protein glycosylation has a major influence on functions of proteins. Studies have shown that aberrations in glycosylation are indicative of disease conditions. This has prompted major research activities for comparative studies of glycoproteins in biological samples. Multiple reaction monitoring (M …
Labeled as emerging organic contaminants, pharmaceuticals and personal care products (PPCPs) have been the focus of global environmental research for over a decade. PPCPs have caused widespread concern due to their extensive use. As PPCPs were designed to correct, enhance, or protect a specific physiological or endocrine condition, their target effects in humans and/or farm stocks are relatively well understood and documented. However, there is limited knowledge about their unintended effects in the environment. To address the occurrence, distribution and fate of PPCPs in the environment, efficient and reliable analytical methods are needed. The relatively low concentration, high polarity, and thermal lability of some PPCPs, together with their interaction with complex environmental matrices, makes their analysis challenging. Sample preparation followed by GC or HPLC separation and mass spectrometry (MS) detection has become the standard approach for evaluating PPCPs in environmental samples. ...
Japans largest platform for academic e-journals: J-STAGE is a full text database for reviewed academic papers published by Japanese societies
Detailed HPLC/MS/MS studies on blood samples collected from normal healthy human subjects were performed to generate a reference of sphingolipid (SPL) levels for future investigations into diseases utilizing blood as a matrix. The impact of sample collection (serum, plasma, and anticoagulants), attributes of blood donors (gender, fasting state) and handling of blood were investigated. In addition, the SPL metabolomic profiles (18C sphingoid backbone, C14 to C26 N-acyl chain) of human plasma were determined. Blood was collected from healthy males and non-pregnant females under fasting and nonfasting conditions with and without various anticoagulants (EDT A, citrate and heparin). Plasma prepared with EDT A was determined to be ideal over the other blood formulations for SPL analyses, yielding the lowest variances in determination of most analyzed SPL classes. Sph1 P levels were higher in serum than plasma (0.67~M vs. 0.32jJM) with no effect on other SPLs in EDTA plasma. There were no variances on ...
ePIC (electronic Publication Information Center) is the official repository for publications and presentations of Alfred Wegener Institute for Polar and Marine Research (AWI)
Close The Infona portal uses cookies, i.e. strings of text saved by a browser on the users device. The portal can access those files and use them to remember the users data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser. ...
Journal of Chemistry is a peer-reviewed, Open Access journal that publishes original research articles as well as review articles on all aspects of fundamental and applied chemistry.

No data available that match "tandem mass spectrometry"


Tandem parallel fragmentation of peptides for mass spectrometry.. Ramos AA1, Yang H, Rosen LE, Yao X. ... of tandem mass spectrometers are sequentially combined to develop parallel collision-induced-dissociation mass spectrometry ( ... We implement the method using a quadrupole time-of-flight tandem mass spectrometer. The instrument is operated in TOF-MS mode ... p2CID MS). Compared to MS/MS spectra, the p2CID mass spectra show increased signal intensities (2-400-fold) and number of ...
Mass spectrometry/mass spectrometry: techniques and applications of tandem mass spectrometry. New York, N.Y: VCH Publishers. ... Tandem mass spectrometry includes triple quadrupole mass spectrometer (QqQ), quad time of flight (Q-TOF), and hybrid mass ... Mass Spectrometry/Mass Spectrometry: Techniques and Applications of Tandem. Chichester: John Wiley & Sons. ISBN 978-0-471-18699 ... Sleno L, Volmer DA (October 2004). "Ion activation methods for tandem mass spectrometry". Journal of Mass Spectrometry. 39 (10 ...
We applied TagGraph to a published human proteomic dataset of 25 million mass spectra and tripled confident spectrum ... Although mass spectrometry is well suited to identifying thousands of potential protein post-translational modifications (PTMs ... Ma, B. et al. PEAKS: powerful software for peptide de novo sequencing by tandem mass spectrometry. Rapid Commun. Mass Spectrom. ... Na, S., Bandeira, N. & Paek, E. Fast multi-blind modification search through tandem mass spectrometry. Mol. Cell. Proteomics 11 ...
Mass spectrometry has become a key technology for modern large-scale protein sequencing. Tandem mass spectrometry, the process ... Decision tree-driven tandem mass spectrometry for shotgun proteomics.. Swaney DL1, McAlister GC, Coon JJ. ... Recent advances in mass spectrometry now permit two discrete, and complementary, types of peptide ion fragmentation: collision- ... The probability of either a ETD or CAD tandem MS event resulting in a high confidence sequence identification for peptide ...
Ion-electron reaction based fragmentation methods (ExD) in tandem mass spectrometry (MS), such as electron capture dissociation ... of a new qQq-FTICR mass spectrometer for post-translational modification analysis and top-down tandem mass spectrometry of ... and can be easily identified using mass spectrometry (MS) [40]. Isomerization does not change the molecular mass of the protein ... 2.3 Mass Spectrometry. Most ECD experiments were performed on a custom built qQq-FTICR MS with a nanospray source and a 7 T ...
Schilling O., auf dem Keller U., Overall C.M. (2011) Protease Specificity Profiling by Tandem Mass Spectrometry Using Proteome- ... Craig, R., and Beavis, R. C. (2004) TANDEM: matching proteins with tandem mass spectra, Bioinformatics 20, 1466-1467.PubMed ... Protease Specificity Profiling by Tandem Mass Spectrometry Using Proteome-Derived Peptide Libraries. ... and identified by liquid chromatography-tandem mass spectrometry. The corresponding nonprime-side sequences are derived ...
Generating Peptide Sequence Tags for Peptide Identification via Tandem Mass Spectrometry ... TANDEM: matching proteins with tandem mass spectra by Robertson Craig, Ronald C. Beavis - Bioinformatics , 2004 ... Summary: Tandem mass spectra obtained from fragmenting peptide ions contain some peptide sequence specific information, but ... Summary: Tandem mass spectra obtained from fragmenting peptide ions contain some peptide sequence specific information, but ...
Californias Experience Implementing a Pilot Newborn Supplemental Screening Program Using Tandem Mass Spectrometry. Lisa ... Californias Experience Implementing a Pilot Newborn Supplemental Screening Program Using Tandem Mass Spectrometry ... Newborn Screening for Isovaleric Acidemia Using Tandem Mass Spectrometry: Data from 1.6 Million Newborns ... Californias Experience Implementing a Pilot Newborn Supplemental Screening Program Using Tandem Mass Spectrometry ...
High Mass-Accuracy LC-MSMS Library The Wiley Registry of Tandem Mass Spectral Data: MS for ID contains 10,000 positive and ... The Wiley Registry of Tandem Mass Spectral Data: MS for ID comes bundled with one of the most accurate search algorithms ... Wiley Registry of Tandem Mass Spectral Data, MS for ID. Herbert Oberacher ... On the Development of a Robust and Transferable Tandem Mass Spectral Library for the Identification of Small Bioorganic ...
... primer on what laboratories need to know to effectively troubleshoot their liquid chromatography-tandem mass spectrometry ... AACC.org // Clinical Laboratory News // All Articles // Troubleshooting Liquid Chromatography-Tandem Mass Spectrometry in the ... Troubleshooting liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems can be intimidating because the technique is ... For example, confirm that the MS/MS detector voltage is appropriate, mass resolution and calibration are correct, and no ion ...
Tandem mass spectrometry identifies many mouse brain O-GlcNAcylated proteins including EGF domain-specific O-GlcNAc transferase ... Tandem mass spectrometry identifies many mouse brain O-GlcNAcylated proteins including EGF domain-specific O-GlcNAc transferase ... A method to form and detect low mass product ions in a quadrupole ion trap mass spectrometer. J Am Soc Mass Spectrom 17:81-84. ... detection and site-analysis of O-GlcNAc-modified glycopeptides by beta-elimination and tandem electrospray mass spectrometry. ...
"Tandem mass spectrometry with collision induced dissociation isolates molecules of a single mass and then breaks them apart. ... The team used an analytical technique called tandem mass spectrometry-using an instrument provided by Lawrence Berkeley Lab and ... Sandia identifies unusual polycyclic aromatic hydrocarbons using tandem mass spectrometry. February 7, 2019 by Michael Padilla ... "Without the tandem component of this new mass spectrometer, each molecules mass is obtained but no information about its ...
Performance Metrics for Liquid Chromatography-Tandem Mass Spectrometry Systems in Proteomics Analyses. Paul A. Rudnick, Karl R ... Performance Metrics for Liquid Chromatography-Tandem Mass Spectrometry Systems in Proteomics Analyses ... 2004) TANDEM: matching proteins with tandem mass spectra. Bioinformatics 20, 1466- 1467. ... Performance Metrics for Liquid Chromatography-Tandem Mass Spectrometry Systems in Proteomics Analyses ...
Tandem mass spectrometry, which has been previously shown by the Turecek lab to be of use in both newborn screening and in ... The Clinical Diagnosis of Porphyrias by Tandem Mass Spectrometry. dc.contributor.advisor. Turecek, Frantisek. en_US. ...
What is Tandem mass spectrometry? Meaning of Tandem mass spectrometry as a finance term. What does Tandem mass spectrometry ... Definition of Tandem mass spectrometry in the Financial Dictionary - by Free online English dictionary and encyclopedia. ... tandem mass spectrometry, hyphenated separation techniques, organic mass spectrometry, inorganic mass spectrometry, structure ... The growth of mass spectrometry and more specifically liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) [2] ...
Using tandem affinity purification (TAP) and mass spectrometry we have identified several novel protein interactions with the ... we have established the AHR-PIN using tandem affinity purification (TAP) and mass spectrometry (MS). Here we report the AHR-PIN ... Gel Electrophoresis and Mass Spectrometry. Samples were separated on a 4-12% Bis-Tris gradient gel (NuPage, Invitrogen) by ... a) Venn diagram of proteins identified by mass spectrometry in 3 data sets of AHR-TAP 30 min TCDD (10 nM) dosing. (b) Table ...
Proteomics Analysis of Protein Kinases by Target Class-selective Prefractionation and Tandem Mass Spectrometry. Josef Wissing, ... Proteomics Analysis of Protein Kinases by Target Class-selective Prefractionation and Tandem Mass Spectrometry ... Proteomics Analysis of Protein Kinases by Target Class-selective Prefractionation and Tandem Mass Spectrometry ... Proteomics Analysis of Protein Kinases by Target Class-selective Prefractionation and Tandem Mass Spectrometry ...
... are normal phase and reversed phase separation strategies for fatty acyls that include detection via tandem mass spectrometry. ... are normal phase and reversed phase separation strategies for fatty acyls that include detection via tandem mass spectrometry. ... Common analytical methodologies involve chromatographic separation and mass spectrometric techniques; however, a single step is ... Common analytical methodologies involve chromatographic separation and mass spectrometric techniques; however, a single step is ...
Measurement of trimethylamineNoxide by stable isotope dilution liquid chromatography tandem mass spectrometry.. Posted on March ... Measurement of trimethylamineNoxide by stable isotope dilution liquid chromatography tandem mass spectrometry. ...
SS: Why is tandem mass spectrometry, LC-MS/MS so important to the work being conducted in your laboratory? ... Tandem mass spectrometry is indispensable to our high-throughput screening program, which covers the analysis of approximately ... Editorial Article: Enhancing the Lives of Children with Tandem Mass Spectrometry. How scientists at Birmingham Womens and ... We wouldnt be able to analyze the quantity of samples that meets the quality of national guidelines without these tandem mass ...
Spectrometry, Mass, Electrospray Ionization Tandem Mass Spectrometry Tyrosine - analogs & derivatives - analysis - metabolism ... Spectrometry, Mass, Electrospray Ionization Tandem Mass Spectrometry Abstract. Analytical methods are generally developed and ... Tandem Mass Spectrometry - methods Waste Water - analysis - chemistry Water Pollutants, Chemical - analysis Water Purification ... Tandem Mass Spectrometry Thyrotropin - blood Young Adult Abstract. Perfluoroalkyl substances (PFASs) are a group of highly ...
Liquid Chromatography/Tandem Mass Spectrometry for the Simultaneous Determination of Alverine and its Metabolite, Monohydroxy ... "Liquid Chromatography/Tandem Mass Spectrometry for the Simultaneous Determination of Alverine and its Metabolite, Monohydroxy ...
Liquid Chromatography and Tandem Ion Trap-Mass Spectrometry. Maryam Khaksari1, Lynn R. Mazzoleni2, Chunhai Ruan3, Peng Song4, ... and Fat-Soluble Vitamins with Liquid Chromatography and Tandem Ion Trap-Mass Spectrometry. ... with a C18 reversed-phase column and an ion trap mass spectrometry (MS) detector coupled with an electrospray ionization (ESI) ...
... tandem mass spectrometry has become routine for organisms with relatively small genomes such as bacteria and yeast. Still, the ... Meyer, J.G. Fast Proteome Identification and Quantification from Data-Dependent Acquisition-Tandem Mass Spectrometry (DDA MS/MS ... Fast Proteome Identification and Quantification from Data-Dependent Acquisition-Tandem Mass Spectrometry (DDA MS/MS) Using Free ... Fast Proteome Identification and Quantification from Data-Dependent Acquisition-Tandem Mass Spectrometry (DDA MS/MS) Using Free ...
Thin layer chromatography, RP-HPLC-DAD and tandem mass spectrometry (LC-MS/MS), were employed to identify the chemical ... LC-Triple Quadrupole Mass Spectrometric Analysis (LC-MS and LC-MS/MS Tandem Mass Spectrometry). An HPLC apparatus (1100 series ... LC-MS/MS Tandem Mass Spectrometry for Analysis of Phenolic Compounds and Pentacyclic Triterpenes in Antifungal Extracts of ... Tandem mass spectrometry (LC-MS/MS) was used to elucidate the molecular masses of flavonoids, triterpenes, ellagitannins and ...
b Masdiag - Diagnostic Mass Spectrometry Laboratory, 33 Stefana Żeromskiego St., PL - 01-882 Warsaw, Poland Tel: +48-602-228- ... of a method for multiple vitamin D metabolite measurements by liquid chromatography coupled with tandem mass spectrometry in ... of a method for multiple vitamin D metabolite measurements by liquid chromatography coupled with tandem mass spectrometry in ... determining four vitamin D metabolites in dried blood spots using liquid chromatography coupled with tandem mass spectrometry. ...
A liquid chromatography tandem mass spectrometry (LC/MS/MS - triple quadrupole) method that facilitates the qualitative and ... A liquid chromatography tandem mass spectrometry (LC/MS/MS - triple quadrupole) method that facilitates the qualitative and ... A liquid chromatography-electrospray tandem mass spectrometry method for the determination of multiple pesticide residues ... A liquid chromatography-electrospray tandem mass spectrometry method for the determination of multiple pesticide residues ...
In this paper, a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the ... A new liquid chromatography-tandem mass spectrometry method for determination of bisoprolol in human plasma samples.. [Gabriela ... Liquid chromatography (LC) coupled with mass spectrometry (MS) detection is one of the most powerful analytical tools for ...
... of Tetracycline and Sulfonamide Antibiotics in Shrimp Tissue using Liquid Chromatography Tandem Quadrupole Mass Spectrometry. ...
... request pricing from manufacturers of Tandem Mass Spectrometers (MS/MS) , Mass Spectrometry ... Xevo TQ-S tandem quadrupole mass spectrometer - designed for the most demanding quantitative UPLC/MS/MS applications. The ... MALDI SYNAPT G2-Si High Definition Mass Spectrometry. Waters. Redefining Resolution - Resolution in 3 Dimensions. MALDI SYNAPT ... The Waters SYNAPT G2-S i High Definition Mass Spectrometry provides complete characterization of complex mixtures and molecules ...
  • We implement the method using a quadrupole time-of-flight tandem mass spectrometer. (nih.gov)
  • The molecules of a given sample are ionized and the first spectrometer (designated MS1) separates these ions by their mass-to-charge ratio (often given as m/z or m/Q). Ions of a particular m/z-ratio coming from MS1 are selected and then made to split into smaller fragment ions, e.g. by collision-induced dissociation, ion-molecule reaction, or photodissociation. (wikipedia.org)
  • These fragments are then introduced into the second mass spectrometer (MS2), which in turn separates the fragments by their m/z-ratio and detects them. (wikipedia.org)
  • Tandem mass spectrometry includes triple quadrupole mass spectrometer (QqQ), quad time of flight (Q-TOF), and hybrid mass spectrometer Triple quadrupole mass spectrometers use the first and third quadrupoles as mass filters. (wikipedia.org)
  • Q-TOF mass spectrometer combines TOF and quadrupole instruments, which cause high mass accuracy for product ions, accurate quantitation capability, and fragmentation experiment applicability. (wikipedia.org)
  • Hybrid mass spectrometer consists of more than two mass analyzers. (wikipedia.org)
  • Multiple stages of mass analysis separation can be accomplished with individual mass spectrometer elements separated in space or using a single mass spectrometer with the MS steps separated in time. (wikipedia.org)
  • and BEBE - four-sector (reverse geometry) mass spectrometer. (wikipedia.org)
  • The first spectrometer ionizes a sample and filter ions of a specific mass to charge ratio. (jove.com)
  • A triple stage quadrupole mass spectrometer, equipped with electrospray ionization (ESI) in the negative mode, is used to determine perchlorate anion. (fda.gov)
  • We describe the implementation of logical MS/MS scans on a commercial linear ion trap mass spectrometer using simple mixtures of amphetamines and fentanyl analogues and argue their utility for complex mixture analysis. (rsc.org)
  • Without the tandem component of this new mass spectrometer, each molecule's mass is obtained but no information about its structure is revealed. (phys.org)
  • Think of a mass spectrometer as an instrument that sorts a container full of mixed nuts based on the weight of each individual nut, but at the end you still don't know whether you sorted peanuts, hazelnuts or walnuts. (phys.org)
  • The customized tandem mass spectrometer that the team used makes it easier to characterize the structure of large molecules by breaking them apart through high-energy collisions in a collision induced dissociation cell. (phys.org)
  • A tandem mass spectrometer is instructed to perform at least two fragmentation scans of a sample with different mass selection window widths using a processor. (freepatentsonline.com)
  • The tandem mass spectrometer includes a mass analyzer that allows variable mass selection window widths. (freepatentsonline.com)
  • The tandem mass spectrometer can also be instructed to perform an analysis of the sample before instructing the tandem mass spectrometer to perform the at least two fragmentation scans of the sample. (freepatentsonline.com)
  • and a processor in communication with the tandem mass spectrometer that instructs the tandem mass spectrometer to perform at least two fragmentation scans of at least two variable precursor mass selection window widths with different precursor mass selection window widths across the mass range of the sample in a single scan of the mass range. (freepatentsonline.com)
  • 2. The system of claim 1, wherein the processor further instructs the tandem mass spectrometer to adjust one or more different acquisition parameters for each different precursor mass selection window. (freepatentsonline.com)
  • Our current immunosuppressant work flow involves precipitating protein from whole blood with acetonitrile containing 100 mmol/L ZnS[O.sub.4] (from Thermo Fisher and Sigma-Aldrich, respectively) and LC-MS/MS analysis with a C18 column and a Quattro Micro mass spectrometer (Waters). (thefreelibrary.com)
  • Address the most stringent analytical challenges for targeted quantitation workflows with the Thermo Scientific™ TSQ Altis™ Triple Quadrupole Mass Spectrometer. (selectscience.net)
  • Identify and quantify more proteins, peptides, lipids, glycans and small molecules accurately and in less time with the Thermo Scientific™ Q Exactive™ HF hybrid quadrupole-Orbitrap mass spectrometer. (selectscience.net)
  • Detection was carried out using Waters Micromass ® Quattro Premier mass spectrometer in multiple reaction monitoring (MRM) mode using turbo ion spray with negative ionization. (scirp.org)
  • A sensitive method has been developed for the trace analysis of alkyl alkylphosphonic acids, metabolites of nerve agents, in urine using a benchtop ion trap mass spectrometer. (biomedsearch.com)
  • An ion trap mass spectrometer in selected reaction monitoring mode provided limits of detection of 0.1 ng/ml for isopropyl, isobutyl, pinacolyl and cyclohexyl methylphosphonic acids and for ethyl ethylphosphonic acid. (biomedsearch.com)
  • The invention of the mass spectrometer has enabled scientists to discover numerous fascinating reactive gas-phase chemical species such as peptide cation radicals. (washington.edu)
  • CID is a slow-heating process in which the ion of study is excited vibrationally via collisions with neutral gas atoms or molecules in the mass spectrometer. (washington.edu)
  • Cannabinoids were separated by liquid chromatography over a BEH C18 column and detected by a Waters TQ-S micro tandem mass spectrometer. (ucsd.edu)
  • Oxygen was used in the collision cell of the inductively coupled plasma-mass spectrometer with MS/MS mode to shift the measured As mass from 75 to 91. (usgs.gov)
  • Sequencing Grade Tandem Mass Spectrometry for Top-Down Proteomics Using Hybrid Electron Capture Dissociation Methods in a Benchtop Orbitrap Mass Spectrometer. (oregonstate.edu)
  • Here, we demonstrate the use of an electromagnetostatic ECD cell to perform ECD and hybrid ECD methods utilizing 193 nm photons (ECuvPD) or collisional activation (EChcD) in a benchtop quadrupole-Orbitrap mass spectrometer. (oregonstate.edu)
  • The eluent was transferred to the mass spectrometer and ionized by heated electrospray negative ionization (HESI) and the analyte was quantified using a six-point calibration curve. (omicsonline.org)
  • Xevo TQ‐S mass spectrometer equipped with an Acquity I‐Class UPLC system with autosampler (Waters Corp. (currentprotocols.com)
  • A powerful tool for obtaining sequence and branching information is multiple-stage tandem ESI-MS (ESI-MS(n)) performed on dephosphorylated and permethylated oligosaccharide material using an ESI-quadrupole ion trap mass spectrometer. (diva-portal.org)
  • In mass spectrometry, fragmentation is the dissociation of energetically unstable molecular ions formed from passing the molecules in the ionization chamber of a mass spectrometer. (wikipedia.org)
  • Tandem mass spectrometry generated fragmentation is typically made in the collision zone (post-source fragmentation) of a tandem mass spectrometer. (wikipedia.org)
  • Tandem parallel fragmentation of peptides for mass spectrometry. (nih.gov)
  • Parallel fragmentations of peptides in the source region and in the collision cell of tandem mass spectrometers are sequentially combined to develop parallel collision-induced-dissociation mass spectrometry (p2CID MS). Compared to MS/MS spectra, the p2CID mass spectra show increased signal intensities (2-400-fold) and number of sequence ions. (nih.gov)
  • A common use of tandem MS is the analysis of biomolecules, such as proteins and peptides. (wikipedia.org)
  • A statistical model is presented for computing probabilities that proteins are present in a sample on the basis of peptides assigned to tandem mass (MS/MS) spectra acquired from a proteolytic digest of the sample. (nih.gov)
  • Primary amines of all peptides are then chemically protected so that after incubation with a test protease, the neo-N-termini of the prime-side cleavage products with exposed α-amines can be specifically biotinylated, enriched, and identified by liquid chromatography-tandem mass spectrometry. (springer.com)
  • Immobilized metal affinity chromatography in combination with tandem mass spectrometry was utilized to identify 19 phosphorylation sites on the five major H1 isoforms plus H1.X. Fourteen of these phosphorylation sites were located on peptides containing the cyclin dependent kinase (CDK) consensus motif (S/T)-P-X-Z (where X is any amino acid and Z is a basic amino acid). (nih.gov)
  • While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet available in all laboratories. (unt.edu)
  • Quantification of serum IgG subclasses by use of subclass-specific tryptic peptides and liquid chromatography-tandem mass spectrometry. (thefreelibrary.com)
  • The use of proteotypic peptides along with liquid chromatography-tandem mass spectrometry (LC-MS/ MS), a technique that does not suffer from antigen excess, has emerged as a useful tool for quantifying proteins (9-12). (thefreelibrary.com)
  • The article discusses a study which quantified multiple amyloid beta peptides in human cerebrospinal fluid (CSF) for preclinical or biomarker discovery using an improved solid-phase extraction-ultraperformance liquid chromatography-mass spectrometry-mass spectrometry (SPE-UPLC-MS-MS). (ebscohost.com)
  • Our methodology is based on the isolation of albumin from blood, its digestion to peptides by pronase E, and the sensitive detection of adducts to the characteristic cysteine-proline-phenylalanine (CPF) tripeptide by liquid chromatography/tandem mass spectrometry. (aspetjournals.org)
  • Identification and characterization of the degradation products was carried out using LC/electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOFMS). (sigmaaldrich.com)
  • The use of a wide range of state-of-the-art techniques including tandem mass spectrometry , time-of-flight mass spectrometry, and NMR were all critical to the identification of the metabolite and confirmation of its identity. (thefreedictionary.com)
  • High performance time-of-flight mass spectrometry (TOF-MS) is applied to the analysis and characterization of complex biological samples. (ebscohost.com)
  • Accurate characterization of carcinogenic DNA adducts using MALDI tandem time-of-flight mass spectrometry. (uncg.edu)
  • The goal of this study is to explore the use of matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF MS) to determine the identity of carcinogen-DNA adducts. (uncg.edu)
  • Sandia National Laboratories scientists Scott Skeen, left, Nils Hansen, center, and Brian Adamson discuss tandem mass spectrometry, which was used for the detection of aliphatically linked polycyclic aromatic hydrocarbons found in soot producing flames. (phys.org)
  • As well as searching for known modification types, Protein Prospector permits the detection and identification of unexpected or novel modifications by searching for any mass shift within a user-specified mass range to any chosen amino acid(s). (mcponline.org)
  • Described in this manuscript are normal phase and reversed phase separation strategies for lipids that include detection of the bioactive primary fatty acid amides and N-acyl glycines via tandem mass spectrometry. (frontiersin.org)
  • 1.1 This procedure covers the determination of selected polyfluorinated compounds (PFCs) in a soil matrix using solvent extraction, filtration, followed by liquid chromatography (LC) and detection with tandem mass spectrometry (MS/MS). These analytes are qualitatively and quantitatively determined by this method. (astm.org)
  • 1.1 This test method covers the determination of dioctyl sulfosuccinate (DOSS) in sea water by direct injection using liquid chromatography (LC) and detection with tandem mass spectrometry (MS/MS). This analyte is qualitatively and quantitatively determined by this test method. (astm.org)
  • In a previous work, coupled-column LC (LC/LC) with direct large-volume sample injection for the analysis of beta 2-agonists in bovine urine was investigated, in view of its combination with thermospray (TSP) tandem mass spectrometric (MS/MS) detection. (unboundmedicine.com)
  • For the first time a quantitative method for the analysis of trace levels of eight chloramphenicol isomers in urine by chiral liquid chromatography in combination with tandem mass spectrometric detection is reported. (wur.nl)
  • Lamotrigine was extracted from plasma through a simple protein precipitation and analyzed by fast liquid chromatography coupled to heated electrospray ionization with tandem mass spectrometric detection. (ovid.com)
  • Differential mobility spectrometry (DMS) has the potential to improve the performance of LC-MS methods for PSTs in terms of selectivity and limits of detection. (springer.com)
  • The determination of lipoxin A(4) has been accomplished by chromatographic separation using a C18 reversed phase column and tandem mass spectrometry detection. (fraunhofer.de)
  • Hereafter, Adding to an improvement on detection accuracy of the heavier element, we are planning to measure 129I with di-molecular pilot beam method as a very important elements especially on our large tandem accelerator. (nii.ac.jp)
  • A 2 μL aliquot of this extract was injected onto a C 18 ‐column, gradient elution was applied and triple‐quadrupole mass spectrometry in positive‐ion mode was used for detection. (separationsnow.com)
  • We applied TagGraph to a published human proteomic dataset of 25 million mass spectra and tripled confident spectrum identifications compared to its original analysis. (nature.com)
  • Summary: Tandem mass spectra obtained from fragmenting peptide ions contain some peptide sequence specific information, but often there is not enough information to completely sequence the original peptide. (psu.edu)
  • The Wiley Registry of Tandem Mass Spectral Data: MS for ID contains 10,000 positive and negative mode spectra for over 1,200 compounds of interest for forensics, toxicology, and pathology. (wiley.com)
  • A flame that was sampled by Sandia National Laboratories scientists against the backdrop of mass spectra and polycyclic aromatic hydrocarbon compounds found inside the flame. (phys.org)
  • Mass spectrometric analyses of protein digests produce large numbers of fragmentation spectra that are not identified by routine database searching strategies. (mcponline.org)
  • Most mass spectrometry search engines are reliable at matching peptide sequences to a significant number of tandem mass spectra. (mcponline.org)
  • Automated Approach for Quantitative Analysis of Complex Peptide Mixtures from Tandem Mass Spectra, Venable, et al. (freepatentsonline.com)
  • SA is chromatographically difficult to separate from MMA and the mass spectra are very similar. (omicsonline.org)
  • The approach that we have developed relies on the use of generic chromatographic and mass spectrometric methods for analysis of mixtures of drugs and metabolites and on correlation analysis of tandem mass spectrometry spectra to distinguish drug-related components from endogenous materials. (aspetjournals.org)
  • Although the library search algorithms are well established for peptide sequences and small molecule electron impact mass spectra, the application of these techniques to small molecule product ion spectra is not well developed. (aspetjournals.org)
  • Full scan DESI mass spectra and tandem (MS/MS) spectra for this representative set of physiological phospho/sphingolipids are presented. (pubfacts.com)
  • The fragmentation step makes it possible to identify and separate ions that have very similar m/z-ratios in regular mass spectrometers. (wikipedia.org)
  • This is accomplished by having mass spectrometers in series. (jove.com)
  • The Principle of Tandem Mass Spectrometry Tandem mass spectrometry is based on coupling mass spectrometers together in a series to analyze complex mixtures. (aacc.org)
  • Tandem mass spectrometers are versatile in that they can be operated using a variety of different scan modes depending on the clinical application. (aacc.org)
  • Histone H1 isoforms isolated from asynchronously grown HeLa cells were subjected to enzymatic digestion and analyzed by nano-flow reversed-phase high performance liquid chromatography (RP-HPLC) tandem mass spectrometry (MS/MS) on both quadrupole ion trap and linear quadrupole ion trap-Fourier transform ion cyclotron resonance mass spectrometers. (nih.gov)
  • The sensitivity, selectivity, flexibility, and ease-of-use provided by hybrid quadrupole-Orbitrap mass spectrometers set the standard for screening, quantitation, identification, and confirmation of targeted and untargeted compounds. (selectscience.net)
  • Prior to these experiments, electrospray ionization in-source fragmentation was generally considered an undesired effect however, electrospray ionization using Enhanced In-Source Fragmentation/Annotation (EISA) has been shown to promote in-source fragmentation that creates fragment ions that are consistent with tandem mass spectrometers. (wikipedia.org)
  • Rapid Communications in Mass Spectrometry 19 (8): 963-969. (ugent.be)
  • Increasingly, tandem mass spectrometry (MS/MS) is being used for newborn screening because this laboratory testing technology substantially increases the number of metabolic disorders that can be detected from dried blood-spot specimens. (cdc.gov)
  • The introduction of tandem mass spectrometry (MS/MS) in the 1990s for population-based newborn screening has enabled health-care providers to detect an increased number of metabolic disorders in a single process by using dried blood-spot specimens routinely collected from newborns ( 13 ). (cdc.gov)
  • Tandem mass spectrometry (TMS) and T-cell-receptor excision circles (TRECs) can identify early-onset ADA deficiency at birth, on dried blood spot (DBS) taken within the routine newborn screening procedure. (aaaai.org)
  • Tandem mass spectrometry, which has been previously shown by the Turecek lab to be of use in both newborn screening and in clinical diagnostics, has the potential to be used in the diagnosis of the porphyrias, as the sensitivity and selectivity of the technique can be utilized to develop more efficient and effective assays than those that currently exist. (washington.edu)
  • State Newborn Screening in the Tandem Mass Spectrometry Era: More False-Positive Results. (thefreedictionary.com)
  • Tandem Mass Spectrometry QA/QC for Newborn Screening: Routine Operations. (slideserve.com)
  • A simple and fast method for analysis of hydroxylated polycyclic aromatic hydrocarbons using pressurized liquid extraction and high performance liquid chromatography utilizing photoionization tandem mass spectrometry was developed. (diva-portal.org)
  • Accordingly, this study shows that high performance liquid chromatography photoionization tandem mass spectrometry can be a good option for the determination of hydroxylated polycyclic aromatic hydrocarbons in complex environmental samples. (diva-portal.org)
  • The method is based on liquid chromatography/atmospheric pressure photoionization tandem mass spectrometry (LC/APPI-MS/MS). Validation was provided in smoked cigarette filter. (spectroscopynow.com)
  • Fast Gas Chromatography with Tandem Mass Spectrometry Analysis of. (ingentaconnect.com)
  • During the past 15 years, liquid chromatography tandem mass spectrometry (LC-MS/MS) has evolved into a vital technology used to perform routine tests in many clinical laboratories. (aacc.org)
  • Individual procedures for foods involve extraction, graphitized carbon solid phase extraction (SPE) cleanup, filtration, followed by ion chromatography-tandem mass spectrometry (IC-MS/MS) determination. (fda.gov)
  • Caroline E. West and Blaine N. Rhodes, "Determination of Urinary Creatinine in Washington State Residents via Liquid Chromatography/Tandem Mass Spectrometry," International Journal of Analytical Chemistry , vol. 2014, Article ID 247316, 6 pages, 2014. (hindawi.com)
  • The analyte is recovered from plasma or brain homogenate by liquid-liquid extraction and subsequently analyzed by liquid chromatography/tandem mass spectrometry (LC/MS/MS). A simple experimental protocol renders the procedure valuable for obtaining information rapidly on brain penetration and plasma exposure of specific classes of compounds. (nih.gov)
  • Troubleshooting liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems can be intimidating because the technique is complex, instrument operation and sample processing are still quite manual, and the majority of assays are laboratory-developed tests (LDTs). (aacc.org)
  • Liquid chromatography/tandem mass spectrometry study of forced degradation of azilsartan medoxomil potassium. (sigmaaldrich.com)
  • Simultaneous determination of beta-blockers in human plasma using liquid chromatography-tandem mass spectrometry. (sigmaaldrich.com)
  • A detailed procedure for the analysis of four beta-blockers, acebutolol, labetalol, metoprolol and propranolol, in human plasma by high-performance liquid chromatography (LC)-tandem mass spectrometry (MS-MS) using an MSpak GF column, which enables direct injection of crude plasma samples, is presented. (sigmaaldrich.com)
  • The growth of mass spectrometry and more specifically liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) [2] continues to accelerate in the clinical laboratory. (thefreedictionary.com)
  • Analytical methods that employ UltraPerformance Liquid Chromatography (UPLC(R)) coupled with tandem mass spectrometry can screen for more than 100 different drug residues at a time at concentrations of less than 10 ng/mL, a big improvement in speed, efficiency, and sensitivity over the traditional seven-plate bioassay method. (thefreedictionary.com)
  • Xia, X. Determination of Tranquilizers in Swine Urine by Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry. (mdpi.com)
  • Measurement of trimethylamineNoxide by stable isotope dilution liquid chromatography tandem mass spectrometry. (strokecenter.org)
  • The method uses liquid chromatography (LC) with a C18 reversed-phase column and an ion trap mass spectrometry (MS) detector coupled with an electrospray ionization (ESI) probe. (aiche.org)
  • This paper presents the development of a high-throughput and sensitive method for determining four vitamin D metabolites in dried blood spots using liquid chromatography coupled with tandem mass spectrometry. (rsc.org)
  • Liquid chromatography--tandem mass spectrometry work flow for parallel quantification of methotrexate and other immunosuppressants. (thefreelibrary.com)
  • As an alternative to reagent-dependent proprietary methods, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, with an improved specificity, can be used to measure methotrexate (2,3). (thefreelibrary.com)
  • Gas chromatography coupled to mass spectrometry (GC/MS) has been extensively applied for determination of volatile, nonpolar, compounds in many applied fields like food safety, environment, or toxicology. (wur.nl)
  • Liquid chromatography tandem mass spectrometry is one of the most specific techniques available in clinical laboratories. (diva-portal.org)
  • A stereoselective, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the determination of R-acenocoumarol and S-acenocoumarol in human plasma was developed and validated at IPRC bioanalytical labs. (scirp.org)
  • Liquid chromatography coupled to mass spectrometry is now the reference method for small analyte determination. (archives-ouvertes.fr)
  • In this article, a bioanalytical method for the extraction and determination of inositol hexaphosphate in whole blood is described by using solid-phase extraction followed by liquid chromatography-mass spectrometry/mass spectrometry using selected reaction monitoring mode for its specificity. (archives-ouvertes.fr)
  • Here, we compare absolute and ranked concentrations of estrone, estradiol, and estriol measured by indirect RIA and of 2-hydroxyestrone and 16α-hydroxyestrone measured by ELISA to the concentrations obtained using a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, which measures 15 estrogen metabolites concurrently. (aacrjournals.org)
  • Direct Quantitation of the Quorum Sensing Signal, Autoinducer-2, in Clinically Relevant Samples by Liquid Chromatography-Tandem Mass Spectrometry. (rti.org)
  • Herein we report a liquid chromatography−tandem mass spectrometric technique that enables reproducible, quantitative, and sensitive measurement of the concentration of autoinducer-2 from a variety of sources. (rti.org)
  • Hyphenation of coupled-column liquid chromatography and thermospray tandem mass spectrometry for the rapid determination of beta 2-agonist residues in bovine urine using direct large-volume sample injection. (unboundmedicine.com)
  • 1.1 This procedure covers the determination of aldicarb, carbofuran, oxamyl and methomyl (referred to collectively as carbamates in this test method) in surface water by direct injection using liquid chromatography (LC) and detected with tandem mass spectrometry (MS/MS). These analytes are qualitatively and quantitatively determined by this method. (environmental-expert.com)
  • Since the introduction of Liquid Chromatography-Tandem Mass Spectrometry (LC/MS/MS) into the clinical research laboratory over a decade ago, it has widely become accepted as the technique of choice for specific and accurate quantitation of many clinically relevant molecules in complex biological matrices. (separationsnow.com)
  • A fast and easy-to-use liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination and quantification of a novel antifungal drug, olorofim (F901318), a member of the novel class of orotomides, in human plasma and serum was developed and validated. (asm.org)
  • The trace analysis of alkyl alkylphosphonic acids in urine using gas chromatography-ion trap negative ion tandem mass spectrometry. (biomedsearch.com)
  • We report here a powerful analytical method based on hydrophilic interaction liquid chromatography-electrospray ionization tandem mass spectrometry (HILIC-ESI-MS/MS), further tested on rat retina. (arvojournals.org)
  • A sensitive and specific ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the measurement of climbazole deposition from hair care products onto artificial skin and human scalp. (uva.nl)
  • Validation of a liquid chromatography-tandem mass spectrometry method for analyzing cannabinoids in oral fluid. (ucsd.edu)
  • A liquid chromatography-heated electrospray ionization-tandem mass spectrometry method including a backflush step was developed and validated to measure lamotrigine concentration in patient plasma. (ovid.com)
  • Liquid chromatography (LC) coupled to mass spectrometry (MS) offers highly selective and sensitive analysis of a wide variety of compounds. (diva-portal.org)
  • Methods: Analysis was performed by liquid chromatography-tandem mass spectrometry in positive ionization mode. (ebscohost.com)
  • A rapid and sensitive liquid chromatography/tandem mass spectrometric (LC-MS/MS) method for simultaneous quantification of fentanyl (F), norfentanyl (NF), despropionylfentanyl (DPF), and hydroxynorfentanyl (OHNF) in human plasma and urine specimens has been developed and validated according to. (ebscohost.com)
  • Determination of homocitrulline in urine of patients with HHH syndrome by liquid chromatography tandem mass spectrometry. (ebscohost.com)
  • A liquid chromatography tandem mass spectrometric method is described for the analysis of homocitrulline in human urine, a key metabolite in the differential diagnosis of hyperammonemia, hyperornithinemia, homocitrullinuria (HHH) syndrome. (ebscohost.com)
  • Hence, this thesis focuses on applying a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to measure BAs in blood samples collected from a bariatric surgery study and a gestational probiotic intervention study. (researchgateway.ac.nz)
  • Derivatized thiols were preconcentrated by online solid-phase extraction (SPE) followed by liquid chromatography separation and electrospray ionization tandem mass spectrometry determination (SPE/LC-ESI-MS/MS). The robustness of the method was validated for wide ranges in pH, salinity, and concentrations of sulfide and dissolved organic carbon (DOC) to cover contrasting natural water types. (diva-portal.org)
  • Using the bottom-up approach and liquid chromatography (LC) in combination with mass spectrometry, the primary structure and sequence microheterogeneity of a plaque-specific anti-β-amyloid (1â€"17) monoclonal antibody (clone 6E10) was characterized. (ebscohost.com)
  • The extraction procedure is very simple and steroid separation is ensured on a BEH C18 column and an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Analysis was done in positive ionization mode (ESI+) and recorded in multiple reaction monitoring mode (MRM). (ovid.com)
  • The sample was directly injected into the turbulent flow liquid chromatography tandem mass spectrometry system (TFLC-MS/MS) for online extraction followed by HPLC separation. (omicsonline.org)
  • Measurement of Pancreatic Polypeptide and Its Peptide Variant in Human Serum and Plasma by Immunocapture-Liquid-Chromatography-Tandem Mass Spectrometry. (omicsonline.org)
  • We developed an Immunocapture-Liquid Chromatography- Tandem Mass Spectrometry (IC-LC-MS/MS) assay to quantify Pancreatic Polypeptide (PP) and its metabolite, PP3-36, in human serum or plasma. (omicsonline.org)
  • Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a powerful technique for the quantification of small molecules in body fluids, but some sample preparation is necessary prior to analysis. (spectroscopyeurope.com)
  • Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is a well-established tool for the identification and quantification of small molecules in research and industrial settings, but the technique has only recently moved into the healthcare arena. (spectroscopyeurope.com)
  • To overcome this limitation, drug metabolism scientists predict likely metabolic transformations and use full-scan liquid chromatography with mass spectrometry (LC-MS) data to search for predicted products of metabolism ( Gibson and Skett, 1986 ). (aspetjournals.org)
  • Methods Serum from 183 women and 146 men was analyzed using equilibrium dialysis (ED), with FT directly measured by liquid chromatography-tandem mass spectrometry. (deepdyve.com)
  • Baiwei Lin and Joseph H. Pease, "A Novel Method for High Throughput Lipophilicity Determination by Microscale Shake Flask and Liquid Chromatography Tandem Mass Spectrometry", Combinatorial Chemistry & High Throughput Screening (2013) 16: 817. (eurekaselect.com)
  • To support therapeutic drug monitoring of patients with cancer, a fast and accurate method for simultaneous quantification of the registered anticancer drugs afatinib, axitinib, ceritinib, crizotinib, dabrafenib, enzalutamide, regorafenib and trametinib in human plasma using liquid chromatography tandem mass spectrometry was developed and validated. (separationsnow.com)
  • The authors have developed a simple, sensitive and precise liquid-liquid extraction aldosterone method for the ABSCIEX API-5000 liquid chromatography and tandem mass spectrometry (LC-MS/MS) system. (bmj.com)
  • The platform consists of two liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods: a reversed-phase method for NRTIs using positive electrospray ionization (ESI) and an ion-pair LC-MS/MS method for the phosphorylated compounds using negative ESI. (eurekamag.com)
  • Zhang G-F, Mortier K, Storojenko S, Van De Steene J, Van Der Straeten D, Lambert W. Free and total para-aminobenzoic acid analysis in plants with high-performance liquid chromatography/tandem mass spectrometry. (ugent.be)
  • In this work, the potential of atmospheric pressure chemical ionization (APCI), a softer form of ionization, combined with GC and a triple quadrupole mass analyzer was investigated, taking pyrethroids as a case study and their determination in fruit and vegetables as example application. (wur.nl)
  • During this presentation the basic principles of operation of the two most commonly used LC- Tandem Mass Spectrometry technologies, triple quadrupole and hybrid-triple quadrupole (QTRAP ® ) systems, will be discussed in terms how they are used to quantitate and /or confirm the identity of clinically relevant compounds in the clinical research laboratory. (separationsnow.com)
  • Age-associated tyrosine nitration of rat skeletal muscle glycogen phosphorylase b: characterization by HPLC-nanoelectrospray-tandem mass spectrometry. (arctichealth.org)
  • Matrix-Assisted Laser Desorption/Ionization (MALDI) combined with tandem Mass Spectrometry (MS/MS) provides a powerful and versatile solution for the molecular characterization of synthetic macromolecules and polymeric materials as well as for imaging the composition and defects of solid polymer surfaces. (bruker.com)
  • The dispersive nature, high mass resolution and sensitivity of the Time-of-Flight mass analysis permit the comprehensive characterization of polymer mixtures and are ideally suitable for monitoring processes that cause even minor mass changes. (bruker.com)
  • Desorption electrospray ionization (DESI) mass spectrometry was evaluated for the characterization of glycerophospholipid standards, including glycerophosphocholine (GPCho), glycerophosphoglycerol (GPGro), glycerophosphoethanolamine (GPEtn), glycerophosphoserine (GPSer), glycerophosphoinositol (GPIns), cardiolipin (CL), and sphingolipid standards, including sulfatides (ST) and sphingomyelin (SM). (pubfacts.com)
  • This experiment is commonly performed to identify transitions used for quantification by tandem MS. In a neutral loss scan, the first mass analyzer scans all the masses. (wikipedia.org)
  • Successful and cost-efficient replacement of immunoassays by tandem mass spectrometry for the quantification of immunosuppressants in the clinical laboratory. (thefreedictionary.com)
  • Guo, M. Studies on Transition Metal-Quercetin Complexes Using Electrospray Ionization Tandem Mass Spectrometry. (mdpi.com)
  • Liu Y, Guo M. Studies on Transition Metal-Quercetin Complexes Using Electrospray Ionization Tandem Mass Spectrometry. (mdpi.com)
  • A fast GC with tandem MS method was developed and validated for multiresidue determination of 95 chemical contaminants (24 synthetic pyrethroids, 17 organochlorines, 17 organophosphorus compounds, 18 polycyclic aromatic hydrocarbons, and 19 polychlorinated biphenyls) in Indian prawns ( Fenneropenaeus indicus ) as per the European Union maximum residual limit requirements. (ingentaconnect.com)
  • High mass accuracy, high resolution, and accurate relative isotope abundance are all applied to the determination of analytes covering a range of. (ebscohost.com)
  • This study describes the extent of structural information directly attainable by a high-performance LCâ€"tandem mass spectrometric method in combination with both protein database searching and de novo sequence determination. (ebscohost.com)
  • Therefore, the main aim of our work was to develop and validate a highly specific and sensitive stereoselective liquid chromatographic-mass spectrometric method for the determination of R- and S-acenocoumarol in human plasma, as well, its application for the enantioselective pharmacokinetics evaluation of both enantiomers after oral dosing in human healthy subjects. (scirp.org)
  • An accelerator mass spectrometry (AMS) system has been developed with a large 12UD tandem static accelerator as a three year project starting from 1992.A 'di-molecular pilot beam method' has been tested successfully and is used for AMS measurements without any modification to the existing tandem system. (nii.ac.jp)
  • Publications] Yasuo Nagashima: 'The Construction of an Accelerator Mass Spectrometry System with 12UD Pelletron Tandem Accelerator at the University of Tsukuba' Proceedings of the Fifth Japan-China Joint Symposium on Accelerator for Nuclear Science and Their Application. (nii.ac.jp)
  • Publications] Y.Nagashima, N.yoshizawa, H.shioya, T.Takahashi, T.Kaikura, Y.Tajima, T,Aoki, and K.Furuno: 'The Construction of an Accelerator Mass Spectrometry System with 12UD Pelletron Tandem Accelerator at the University of Tsukuba. (nii.ac.jp)
  • This is a method of mass spectrometry that ion fragmentation (m/z) ratio determined through a time of flight measurement. (wikipedia.org)
  • Ion-electron reaction based fragmentation methods (ExD) in tandem mass spectrometry (MS), such as electron capture dissociation (ECD) and electron transfer dissociation (ETD) represent a powerful tool for biological analysis. (springer.com)
  • Details and Download Full Text PDF: Desorption electrospray ionization (DESI) mass spectrometry and tandem mass spectrometry (MS/MS) of phospholipids and sphingolipids: ionization, adduct formation, and fragmentation. (pubfacts.com)
  • Fragmentation that occurs in tandem mass spectrometry experiments has been a recent focus of research as this data helps facilitate the identification of molecules. (wikipedia.org)
  • Several modifications never previously reported in proteomics data were identified in these standard data sets using this mass modification searching approach. (mcponline.org)
  • There are many search engines available to the researcher for the analysis of proteomics data produced by tandem mass spectrometry. (mcponline.org)
  • The instrument is operated in TOF-MS mode that allows the ions from source region broadband-passing the first mass analyzer to enter the collision cell. (nih.gov)
  • By doing tandem mass spectrometry in time, the separation is accomplished with ions trapped in the same place, with multiple separation steps taking place over time. (wikipedia.org)
  • Cooks advanced this analytical capability with the introduction of tandem mass spectrometry in which selected ions generated from complex mixtures are further fragmented and the masses of the fragment ions determined. (thefreedictionary.com)
  • This might also complicate the application of tandem MS due to lack of specific/abundant precursor ions. (wur.nl)
  • In the first part of this work, which includes Chapters 2-5, the electronic structures of ETD-formed z-fragment ions were studied in detail using tandem mass spectrometry and molecular dynamics simulations. (washington.edu)
  • The feasibility of global glycoprotein analysis by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and infrared multiphoton dissociation (IRMPD) tandem mass spectrometry is demonstrated. (lu.se)
  • Tandem mass spectrometry, also known as MS/MS or MS2, is a technique in instrumental analysis where two or more mass analyzers are coupled together using an additional reaction step to increase their abilities to analyse chemical samples. (wikipedia.org)
  • Topics include nucleolar localization of adenovirus core proteins, tandem mass spectrometry , the transforming activities of adenovirus oncogenes, large-scale purification and crystallization of adenovirus hexon, and phylogenetic analysis of adenovirus sequences. (thefreedictionary.com)
  • Tandem mass spectrometry (MS/MS) is among one of the most powerful tools in glycoconjugate and carbohydrate analysis. (unl.edu)
  • Tandem mass spectrometry is indispensable to our high-throughput screening program, which covers the analysis of approximately 75,000 dried blood spot samples a year. (selectscience.net)
  • The instrument enables mass spectrum measurement for qualitative analysis or identification of unknowns and Selected Ion Monitoring (SIM) and MRM Measurement for quantitation of trace elements. (utm.my)
  • Tandem mass spectrometry multiplex analysis of methylated and non‐methylated urinary Gb3 isoforms in Fabry disease patients. (currentprotocols.com)
  • Among the current methods for DNA adduct analysis, mass spectroscopic method allows the direct measurement of unlabeled DNA adducts. (uncg.edu)
  • Desorption electrospray ionization (DESI) mass spectrometry has been used for the imaging and analysis of rat spinal cord cross sections. (pubfacts.com)
  • J Am Soc Mass Spectrom 2008 Apr 27;19(4):531-43. (pubfacts.com)
  • J Am Soc Mass Spectrom 2010 Jul 28;21(7):1177-89. (pubfacts.com)
  • Each instrumental configuration utilizes a unique mode of mass identification. (wikipedia.org)
  • On the Development of a Robust and Transferable Tandem Mass Spectral Library for the Identification of Small Bioorganic Molecules. (wiley.com)
  • 10 ppm) mass measurement allowed identification of human glycoproteins and revealed differences in glycosylation. (lu.se)
  • In tandem mass spectrometry in space, the separation elements are physically separated and distinct, although there is a physical connection between the elements to maintain high vacuum. (wikipedia.org)
  • Interest in the clinical utility of mass spectrometry continues to grow, evidenced by the ever growing number of LC-MS/MS publications and conferences, as well as the recent launch of AACC's Mass Spectrometry and Separation Sciences Division. (aacc.org)
  • The procedure comprises (i) screening experiments to identify the most important parameters, (ii) LC studies to ensure sufficient chromatographic separation, (iii) extended infusion experiments in order to maximize precursor signal(s), and in the case of tandem MS (iv) extended infusion experiments to determine optimal conditions for collision induced dissociation and when applicable also ion trap settings. (diva-portal.org)
  • The parallel approach using LC coupled to both inductively coupled plasma (ICP) mass spectrometry, and electrospray ionization (ESI) tandem MS is also evaluated as a tool to identify unknown siderophores in a sample. (diva-portal.org)
  • Over the last few decades, inductively coupled plasma mass spectrometry (ICP-MS) has been increasingly used in the nuclear sector as a rapid alternative to decay counting techniques for long-lived radionuclides, as well as an expanding range of shorter-lived radionuclides. (soton.ac.uk)
  • Warwick, Phillip , Russell, Benjamin , Croudace, Ian and Zacharauskas, Zilvinas (2019) Evaluation of inductively coupled plasma tandem mass spectrometry for radionuclide assay in nuclear waste characterisation. (soton.ac.uk)
  • The tandem mass spectroscopy market is expected to witness the highest growth. (prnewswire.com)
  • Publications] Yasuo Nagashima: 'Accelerator mass spectroscopy with 14C and 26A1 at the University of Tsukuba' Nuclear Instruments and Methods in Physics Research. (nii.ac.jp)
  • Judy Stone, who works for TPMG Kaiser Regional Laboratory, has been using tandem mass spectrometry technologies for years to conduct testing of fewer than 100 samples per day. (thefreedictionary.com)
  • The researchers used tandem mass spectrometry to retrospectively analyze dust samples taken from a 350- to 420-head pig-fattening farm from 1981 to 2000. (thefreedictionary.com)
  • As far as we know, hydroxylated polycyclic aromatic hydrocarbons were determined in wood smoke and soil samples using photoionization mass spectrometry for the first time in this present study. (diva-portal.org)
  • Tandem mass spectrometry (MS/MS) has enabled research workers to analyze organic biological samples because the primary idea inception. (exposed-skin-care.net)
  • Imaging mass spectrometry allows for the direct investigation of tissue samples to identify specific biological compounds and determine their spatial distributions. (pubfacts.com)
  • This method adheres to multiple reaction monitoring (MRM) mass spectrometry. (astm.org)
  • This test method adheres to selected reaction monitoring (SRM) mass spectrometry. (astm.org)
  • When using multiple quadrupoles, they can act as both mass analyzers and collision chambers. (wikipedia.org)
  • The method uses two mass filters arranged sequentially with a collision cell between them. (aacc.org)
  • Tandem mass spectrometry with collision induced dissociation isolates molecules of a single mass and then breaks them apart. (phys.org)
  • Glycerophospholipids and sphingolipids, as well as fatty acids, were detected in both the negative and positive ion modes and identified through tandem mass spectrometry (MS/MS) product ion scans using collision-induced dissociation and accurate mass measurements. (pubfacts.com)
  • The glycerophospholipids and sphingolipids that appear as intense signals in both the negative ion and positive ion modes were identified by tandem mass spectrometry product ion scans using collision-induced dissociation. (pubfacts.com)
  • Although mass spectrometry is well suited to identifying thousands of potential protein post-translational modifications (PTMs), it has historically been biased towards just a few. (nature.com)
  • Creasy, D. M. & Cottrell, J. S. Unimod: protein modifications for mass spectrometry. (nature.com)
  • Tandem mass spectrometry can be used to solve a number of protein structural problems that are not amenable to conventional methods for amino acid sequencing. (sciencemag.org)
  • First, by microsomal incubations of APAP in presence of CPF and/or intact albumin, in vitro reference adducts were generated to determine the mass spectrometric characteristics of the expected CPF adducts and to confirm their formation on pronase E digestion of the alkylated protein. (aspetjournals.org)
  • Tandem in time MS instruments do not use the modes described next, but typically collect all of the information from a precursor ion scan and a parent ion scan of the entire spectrum. (wikipedia.org)
  • For a precursor ion scan, the product ion is selected in the second mass analyzer, and the precursor masses are scanned in the first mass analyzer. (wikipedia.org)
  • In a product ion scan, a precursor ion is selected in the first stage, allowed to fragment and then all resultant masses are scanned in the second mass analyzer and detected in the detector that is positioned after the second mass analyzer. (wikipedia.org)
  • The formation of a highly abundant (quasi) molecular ion was the main goal because of the enhanced selectivity when used as precursor ion in tandem MS. The addition of water as a modifier was tested to promote the generation of protonated molecules, resulting in notable improvement of sensitivity and selectivity for most compounds. (wur.nl)
  • This study evaluates the potential application of tandem ICP-MS/MS for the measurement of a range of radionuclides of interest to nuclear decommissioning and waste management. (soton.ac.uk)
  • Attempts have been made to combine IMAC with electrospray ionization mass spectrometry (ESI-MS) to characterize marine Cu ligands, but results have proven inconclusive due to the lack of tandem mass spectrometry (MS/MS) data to confirm ligand recovery. (frontiersin.org)
  • Desorption electrospray ionization imaging mass spectrometry of lipids in rat spinal cord. (pubfacts.com)
  • Lipid profiles of canine invasive transitional cell carcinoma of the urinary bladder and adjacent normal tissue by desorption electrospray ionization imaging mass spectrometry. (pubfacts.com)
  • Desorption electrospray ionization mass spectrometry (DESI-MS) was used in an imaging mode to interrogate the lipid profiles of thin tissue sections of canine spontaneous invasive transitional cell carcinoma of the urinary bladder (a model of human invasive bladder cancer) as well as adjacent normal tissue from four different dogs. (pubfacts.com)
  • On the other hand, MS/MS has superior selectivity for many analytes since it recognizes them by at least two physical properties-their precursor and product ion mass. (aacc.org)
  • Systems and methods are used to analyze a sample using variable mass selection window widths. (freepatentsonline.com)
  • The selection of the different mass selection window widths can be based on one or more properties of sample compounds. (freepatentsonline.com)
  • 5. The system of claim 1, wherein the precursor mass selection window widths are based on one or more properties of sample compounds. (freepatentsonline.com)
  • This webinar is aimed at potential newcomers to Tandem Mass Spectrometry as well as established users within the clinical research fraternity. (separationsnow.com)
  • THPLC-Tandem Mass Spectrometry is a powerful analytical tool in order to define the fingerprint of the molecular species of complex mixture of polar lipid extracts, such as phospholipids (PL). This technique can be of interest in several research fields, such as biochemistry, food technology and the pharmaceutical industry. (univpm.it)
  • Mass Spectrometry Conditions: For those using Waters Micromass equipment, we have found that lowering the capillary voltage from 3.25 kV to 0.58 kV improves sensitivity by two fold. (fda.gov)
  • OBJECTIVE To establish criteria for the diagnosis of medium chain acyl-CoA dehydrogenase (MCAD) deficiency in the UK population using a method in which carnitine species eluted from blood spots are butylated and analysed by electrospray ionisation tandem mass spectrometry (ESI-MS/MS). (bmj.com)
  • Mass spectrometry offers a means to overcome problems with method-dependent bias between competitive immunoassays for aldosterone. (bmj.com)
  • A total of five degradation products (DP 1 to DP 5) were formed under various stress conditions and their structures were proposed with the help of tandem mass spectrometry (MS/MS) experiments and accurate mass data. (sigmaaldrich.com)

No images available that match "tandem mass spectrometry"