Spectrometry, Mass, Electrospray Ionization: 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.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Tandem Mass Spectrometry: 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.Chromatography, Liquid: Chromatographic techniques in which the mobile phase is a liquid.Ions: 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.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Phenindione: An indandione that has been used as an anticoagulant. Phenindione has actions similar to WARFARIN, but it is now rarely employed because of its higher incidence of severe adverse effects. (From Martindale, The Extra Pharmacopoeia, 30th ed, p234)Proteomics: The systematic study of the complete complement of proteins (PROTEOME) of organisms.Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization: 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.Fourier Analysis: 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)Peptides: 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.Molecular Sequence Data: 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.Amino Acid Sequence: 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.Proteome: The protein complement of an organism coded for by its genome.Spectroscopy, Fourier Transform Infrared: 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.Isotope Labeling: 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.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Gases: 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)Plastids: Self-replicating cytoplasmic organelles of plant and algal cells that contain pigments and may synthesize and accumulate various substances. PLASTID GENOMES are used in phylogenetic studies.PhosphopeptidesProteins: 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.Complex Mixtures: 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.Glycopeptides: 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.Molecular Structure: 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.Atmospheric Pressure: The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.Nanotechnology: The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.Sensitivity and Specificity: 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)Indicators and Reagents: 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)Calibration: 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.Isomerism: 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)Deuterium: Deuterium. The stable isotope of hydrogen. It has one neutron and one proton in the nucleus.Infrared Rays: That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.Air Ionization: The dissociation of molecules in the air into positive and negative ions under the influence of an electric field.Cyclotrons: 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.Reference Standards: 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.Electrons: 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.Enkephalin, Leucine: One of the endogenous pentapeptides with morphine-like activity. It differs from MET-ENKEPHALIN in the LEUCINE at position 5. Its first four amino acid sequence is identical to the tetrapeptide sequence at the N-terminal of BETA-ENDORPHIN.Hybrid Cells: Any cell, other than a ZYGOTE, that contains elements (such as NUCLEI and CYTOPLASM) from two or more different cells, usually produced by artificial CELL FUSION.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Spectrometry, Mass, Secondary Ion: 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.Limit of Detection: Concentration or quantity that is derived from the smallest measure that can be detected with reasonable certainty for a given analytical procedure.Solid Phase Extraction: 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.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Peptide Mapping: 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.Anthranilate Synthase: An enzyme that catalyzes the formation of anthranilate (o-aminobenzoate) and pyruvic acid from chorismate and glutamine. Anthranilate is the biosynthetic precursor of tryptophan and numerous secondary metabolites, including inducible plant defense compounds. EC 4.1.3.27.Trypsin: 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.Spectrometry, Mass, Fast Atom Bombardment: 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.Magnetic Resonance Spectroscopy: 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).Glycerophospholipids: 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.Protons: Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Cattle: 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.Oligosaccharides: 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.Metabolomics: 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.Electrophoresis, Gel, Two-Dimensional: 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.Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Electrophoresis, Capillary: 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)Molecular Weight: The sum of the weight of all the atoms in a molecule.Spectroscopy, Mossbauer: A spectroscopic technique which uses the Mossbauer effect (inelastic scattering of gamma radiation resulting from interaction with heavy nuclei) to monitor the small variations in the interaction between an atomic nucleus and its environment. Such variations may be induced by changes in temperature, pressure, chemical state, molecular conformation, molecular interaction, or physical site. It is particularly useful for studies of structure-activity relationship in metalloproteins, mobility of heavy metals, and the state of whole tissue and cell membranes.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Equipment Design: Methods of creating machines and devices.Carbohydrate Conformation: The characteristic 3-dimensional shape of a carbohydrate.Sequence Analysis, Protein: 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.PolysaccharidesDisaccharides: Oligosaccharides containing two monosaccharide units linked by a glycosidic bond.Stereoisomerism: 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)Substance Abuse Detection: Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.Glycosylation: 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.Solvents: 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)Oxygen Isotopes: 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.Deuterium Exchange Measurement: A research technique to measure solvent exposed regions of molecules that is used to provide insight about PROTEIN CONFORMATION.Chromatography, Reverse-Phase: 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.Doping in Sports: Illegitimate use of substances for a desired effect in competitive sports. It includes humans and animals.Horses: 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.Kinetics: The rate dynamics in chemical or physical systems.Mandibular Osteotomy: Intraoral OSTEOTOMY of the lower jaw usually performed in order to correct MALOCCLUSION.Sulfoglycosphingolipids: GLYCOSPHINGOLIPIDS with a sulfate group esterified to one of the sugar groups.Microchemistry: 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.Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Oxidation-Reduction: 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).Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Pharmaceutical Preparations: Drugs intended for human or veterinary use, presented in their finished dosage form. Included here are materials used in the preparation and/or formulation of the finished dosage form.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cations: Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.Glycosides: 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)Sydnones: OXADIAZOLES bearing an oxygen at the 5-position. They are mesoionic, with delocalized positive and negative charges.Hybridization, Genetic: The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Protein Processing, Post-Translational: 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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Metals, Alkali: 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.Hydrogen: 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.Chemical Warfare Agents: Chemicals that are used to cause the disturbance, disease, or death of humans during WARFARE.Miniaturization: The design or construction of objects greatly reduced in scale.Drug Stability: The chemical and physical integrity of a pharmaceutical product.Metals: Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)Protein Binding: 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.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Fractionation, Field Flow: Separation of molecules and particles by a simultaneous action of carrier liquid flow and focusing field forces (electrical, sedimentation, or thermal), without a stationary phase.Explosive Agents: Substances that are energetically unstable and can produce a sudden expansion of the material, called an explosion, which is accompanied by heat, pressure and noise. Other things which have been described as explosive that are not included here are explosive action of laser heating, human performance, sudden epidemiological outbreaks, or fast cell growth.Spectrophotometry, Ultraviolet: 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)Flame Ionization: Pyrolysis of organic compounds at the temperature of a hydrogen-air flame to produce ionic intermediates which can be collected and the resulting ion current measured by gas chromatography.Benzyl Alcohols: Alcohols derived from the aryl radical (C6H5CH2-) and defined by C6H5CHOH. The concept includes derivatives with any substituents on the benzene ring.Chromatography, Thin Layer: 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)Escherichia coli: 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.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Germanium: A rare metal element with a blue-gray appearance and atomic symbol Ge, atomic number 32, and atomic weight 72.63.Anions: Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Chemical Fractionation: 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)Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Cadmium Radioisotopes: Unstable isotopes of cadmium that decay or disintegrate emitting radiation. Cd atoms with atomic weights 103-105, 107, 109, 115, and 117-119 are radioactive cadmium isotopes.Metabolome: The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.Lipids: 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)Acetonitriles: Compounds in which a methyl group is attached to the cyano moiety.Crown Ethers: Macrocyclic polyethers with the repeating unit of (-CH2-CH2-O)n where n is greater than 2 and some oxygens may be replaced by nitrogen, sulfur or phosphorus. These compounds are useful for coordinating CATIONS. The nomenclature uses a prefix to indicate the size of the ring and a suffix for the number of heteroatoms.Capillary Action: A phenomenon in which the surface of a liquid where it contacts a solid is elevated or depressed, because of the relative attraction of the molecules of the liquid for each other and for those of the solid. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Ion Channels: Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Serum Albumin, Bovine: Serum albumin from cows, commonly used in in vitro biological studies. (From Stedman, 25th ed)Databases, Protein: Databases containing information about PROTEINS such as AMINO ACID SEQUENCE; PROTEIN CONFORMATION; and other properties.X-Ray Microtomography: X-RAY COMPUTERIZED TOMOGRAPHY with resolution in the micrometer range.Drugs, Chinese Herbal: 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.Chemistry Techniques, Analytical: Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.Forensic Sciences: Disciplines that apply sciences to law. Forensic sciences include a wide range of disciplines, such as FORENSIC TOXICOLOGY; FORENSIC ANTHROPOLOGY; FORENSIC MEDICINE; FORENSIC DENTISTRY; and others.Phosphatidylcholines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.Chemistry, Physical: The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.Plasmalogens: GLYCEROPHOSPHOLIPIDS in which one of the two acyl chains is attached to glycerol with an ether alkenyl linkage instead of an ester as with the other glycerophospholipids.Liquid-Liquid Extraction: 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)Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Argon: Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.Analytic Sample Preparation Methods: 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.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Bacterial Proteins: Proteins found in any species of bacterium.Oligonucleotides: Polymers made up of a few (2-20) nucleotides. In molecular genetics, they refer to a short sequence synthesized to match a region where a mutation is known to occur, and then used as a probe (OLIGONUCLEOTIDE PROBES). (Dorland, 28th ed)Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Disulfides: Chemical groups containing the covalent disulfide bonds -S-S-. The sulfur atoms can be bound to inorganic or organic moieties.Physicochemical Phenomena: The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.Glycerylphosphorylcholine: 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.Phospholipids: Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.Methanol: A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Phase Transition: A change of a substance from one form or state to another.Helium: Helium. A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics. (Dorland, 27th ed)Forensic Medicine: The application of medical knowledge to questions of law.Volatilization: A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.Monosaccharides: 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)Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Chromatography, Gas: 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.Capillary Electrochromatography: A separation technique which combines LIQUID CHROMATOGRAPHY and CAPILLARY ELECTROPHORESIS.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Software: Sequential operating programs and data which instruct the functioning of a digital computer.Glucuronides: 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.Coordination Complexes: Neutral or negatively charged ligands bonded to metal cations or neutral atoms. The number of ligand atoms to which the metal center is directly bonded is the metal cation's coordination number, and this number is always greater than the regular valence or oxidation number of the metal. A coordination complex can be negative, neutral, or positively charged.Muramidase: A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.
The Orbitrap analyzer can be interfaced to a linear ion trap (LTQ Orbitrap family of instruments), quadrupole mass filter (Q ... By processing data in a manner similar to that used in Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), ... of the technology was carried out using the direct injection of ions from an external laser desorption and ionization ion ... of injection works well with pulsed sources such as MALDI but cannot be interfaced to continuous ion sources like electrospray ...
Penning trap) or quadrupole ion trap (Paul trap) mass spectrometer. Fragmentation for tandem mass spectrometry is accomplished ... "Top-Down Proteomics on a Chromatographic Time Scale Using Linear Ion Trap Fourier Transform Hybrid Mass Spectrometers". ... Proteins are typically ionized by electrospray ionization and trapped in a Fourier transform ion cyclotron resonance ( ... that uses an ion trapping mass spectrometer to store an isolated protein ion for mass measurement and tandem mass spectrometry ...
... mass spectrometry is categorized by approaches of mass analyzers: magnetic-sector, quadrupole mass analyzer, quadrupole ion ... There are several ionization methods: electron impact, chemical ionization, electrospray, fast atom bombardment, matrix ... Several examples are in popular use today and new hybrid techniques are under development. For example, gas chromatography-mass ... trap, time-of-flight, Fourier transform ion cyclotron resonance, and so on. Electroanalytical methods measure the potential ( ...
"Nano electrospray combined with a quadrupole ion trap for the analysis of peptides and protein digests". Journal of the ... and HCD where the peptide precursor is initially subjected to an ion/ion reaction with fluoranthene anions in a linear ion trap ... "Protein sequence information by matrix-assisted laser desorption/ionization in-source decay mass spectrometry". Mass ... Electric sector The notation can be combined to indicate various hybrid instrument, for example QqQ - Triple quadrupole mass ...
"Tandem-in-space and tandem-in-time mass spectrometry: Triple quadrupoles and quadrupole ion traps". Analytical Chemistry. 62 ( ... In the TQMS, several ionization methods can be employed. Some of these include electrospray ionization, chemical ionization, ... Hybrid mass spectrometer Morrison, J. D. (1991), "Personal reminiscences of forty years of mass spectrometry in Australia", ... Morrison's linear arrangement of the three quadrupoles probed the construction of the first triple-quadrupole mass spectrometer ...
... accuracy of targeted mass spectrometry using the recently developed hybrid Fusion quadrupole-Orbitrap-linear ion trap mass ... External accumulation of ions for enhanced electrospray ionization fourier transform ion cyclotron resonance mass spectrometry ... and the Fusion quadrupole-Orbitrap-linear ion trap (Q-OT-IT) mass spectrometers, use high-capacity multipole ion traps, which ... Accumulated Ion Monitoring for Targeted Proteomics using Hybrid Quadrupole-Orbitrap-Linear Ion Trap (Q-OT-IT) Instrument. ...
... using an Applied Biosystems 4000 Qtrap hybrid triple quadrupole/linear ion trap mass spectrometer (Applied Biosystems, Foster ... glycerophospholipids from both vesicles and controls was accomplished by electrospray ionization-tandem mass spectrometry (ESI- ... Electrospray ionization mass spectroscopic analysis of human erythrocyte plasma membrane phospholipids. Proc Natl Acad Sci U S ... a quantitative electrospray ionization/mass spectrometric analysis. Biochemistry 2002;41:2075-2088. ...
... analysis using the 4000 Q-Trap Quadrupole Linear Ion Trap Hybrid Mass Spectrometer (Applied Biosystems) equipped with Acquity ... interstitial fraction and subjected to liquid chromatography-electrospray ionisation mass spectrometry/tandem mass spectrometry ... Taguchi, R., Nishijima, M. and Shimizu, T. (2007). Basic analytical systems for lipidomics by mass spectrometry in Japan. ... Meissner, G. (1983). Monovalent ion and calcium ion fluxes in sarcoplasmic reticulum. Mol. Cell. Biochem. 55,65 -82. ...
Mass spectrometry based proteomics techniques are now proving to be useful for evolutionary plant biologists. What was ... using a QTRAP hybrid triple quadrupole/linear ion trap MS/MS mass spectrometer equipped with a nano-electrospray ionization ... Mass spectrometry-based proteomics techniques are now proving to be useful for evolutionary plant biologists. What was ... oxycedrus samples were run on a QSTAR Pulsar I hybrid quadrupole-TOF MS/MS mass spectrometer (Applied Biosystems). Liquid ...
The ESI-MS/MS analysis was performed using a 4000Q-TRAP quadrupole linear ion trap hybrid mass spectrometer (Applied Biosystems ... For analysis using liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) and imaging mass ... Liquid chromatography/electrospray ionization tandem mass spectrometry.. For LC/ESI-MS/MS, spinal cord tissue blocks were ... Mass spectrometry conditions.. Tandem mass spectrometry analysis was performed in both positive, for phosphatidylcholines (PCs ...
Endocannabinoid content was analyzed using a 5500 Q-TRAP hybrid/triple quadrupole linear ion trap mass spectrometer (Applied ... and related compounds in rat brain using liquid chromatography-tandem electrospray ionization mass spectrometry. Anal Biochem ... with electrospray ionization in positive mode. The mass spectrometer was interfaced to a Shimadzu SIL-20AC XR auto-sampler ... 1-arachidonoylglycerol and arachidonic acid in mouse brain tissue using liquid chromatography/tandem mass spectrometry. J Mass ...
... coupled to a hybrid linear ion trap-triple quadrupole mass spectrometer (QTRAP 5500; ABSCIEX, Foster City, CA). Extract (10 μL ... For comparison of DI/EI-SIM with electrospray ionization-mass spectrometry (ESI-MS), three samples of meibum (collected as ... Electron ionization-mass spectrometry was conducted using a single quadrupole gas chromatography-mass spectrometry (GC-MS) ... a parallel analysis of free cholesterol using electrospray ionization-tandem mass spectrometry (ESI-MS/MS) was completed. Lipid ...
Quantitation of isobaric phosphatidylcholine species in human plasma using a hybrid quadrupole linear ion-trap mass ... Elucidation of double bond position in unsaturated lipids by ozone electrospray ionization mass spectrometry. Anal. Chem. 79, ... two-dimensional liquid chromatography-mass spectrometry vs. liquid chromatography-trapped-ion-mobility-mass spectrometry. J. ... ions generated by electrospray ionization of a plasma lipid extract were transmitted through the quadrupole in 1 Da segments. ...
... chromatography-mass spectrometry method using electrospray ionization in negative ion mode coupled with a hybrid quadrupole ... spectrometry method using electrospray ionization in negative ion mode coupled with a hybrid quadrupole linear ion trap and ... in Capers by LC-ESI using a hybrid linear ion trap with Fourier-transform ion cyclotron resonance mass spectrometry (LC-ESI-LTQ ... in Capers by LC-ESI using a hybrid linear ion trap with Fourier-transform ion cyclotron resonance mass spectrometry (LC-ESI-LTQ ...
... coupled with an electrospray ionization hybrid linear ion trap quadrupole/Orbitrap mass spectrometry, has been used to ... strategy-based-on-liquid-chromatography-electrospray-ionization-linear-ion-trap-quadrupole-orbitrap-mass-spectrometry-for- ... Strategy Based on Liquid Chromatography/Electrospray Ionization Linear Ion Trap Quadrupole/Orbitrap Mass Spectrometry for ... The planar linear ion trap (PLIT) is a version of the two-dimensional linear quadrupole ion trap constructed using two facing ...
... combined with ElectroSpray Ionization (ESI) and Fourier-Transform Mass Spectrometry (FTMS), based on a quadrupole-Orbitrap ... performed in a linear ion trap mass spectrometer, were exploited for structural elucidation purposes... ... In this paper, the authors report an objective, quantitative 2D strain imaging approach using a hybrid deformable registration ... a study by hydrophilic interaction liquid chromatography-electrospray ionization Fourier transform mass spectrometry. ...
Mass Spectrom. 14: 1130-1147, 2003.. *DJ Douglas, AJ Frank & D Mao: Linear ion traps in mass spectrometry. Mass Spectrom. Rev. ... J. Mass Spectrom. 37: 241-253, 2002.. *RB Cole: Some tenets pertaining to electrospray ionization mass spectrometry. J. Mass ... Mass Spectrom. 17: 1056-1064, 2003.. *FA Londry & JW Hager: Mass selective axial ion ejection from a linear quadrupole ion trap ... Performance evaluation of a hybrid linear ion trap/orbitrap mass spectrometer. Anal. Chem. 78: 2113-2120, 2006. ...
Mass Spectrometry in the Biological Sciences: A Tutorial by Michael L. Gross, 9780792315391, available at Book Depository with ... Hybrid Tandem Mass Spectrometry.- 3. Triple Quadrupole Mass Spectrometry.- 4. Quadrupole Ion Trap Mass Spectrometers for ... Ion Detection in Mass Spectrometry.- II: Methods in Mass Spectrometry.- 8. Electrospray Mass Spectrometry.- 9. Laser Desorption ... The Mass Spectrometric Determination of Retro-Inverso Linear Peptides.- 24. Mass Spectrometry in Studies of O-Linked ...
2.5 High-resolution electrospray ionization mass spectrometry. Top-down mass spectrometry was performed on a hybrid linear ion- ... A hybrid linear ion-trap Fourier-transform ion cyclotron resonance mass spectrometer was used for top-down characterization of ... 2.4 Low resolution electrospray ionization mass spectrometry. LC-MS+ experiments were performed using a triple quadrupole ... The hybrid linear ion-trap FT-ICR mass spectrometer used for the top-down MS experiments achieved mass accuracy on precursor ...
GS-HNE was carried out using a Shimadzu HPLC coupled with an AB Sciex 4000-Qtrap hybrid linear ion trap triple quadrupole mass ... The MS was operated in the positive electrospray ionization mode with optimal ion source settings with a declustering potential ... liquid chromatography-tandem mass spectrometry. mAb. monoclonal antibody. MBB. monobromobimane. MnSOD. Mn-superoxide dismutase ... GS-HNE, measured by mass spectrometry, was lower in the hearts of treatment-naïve Mrp1−/− versus WT mice (P , 0.05). DOX ...
... over 100 structural variants of Fn lipid A were characterized using electrospray ionization (ESI) with a linear ion trap (IT) ... hybrid mass spectrometer (Shaffer; Ting). These results were generated using hierarchical tandem mass spectrometry (HiTMS) by ... as they do not always adhere to optimal ionization and fragmentation considerations for triple quadrupole instruments. By ... The present study aimed to investigate the suitability of high-resolution ion mobility spectrometry-mass spectrometry (IMS-MS) ...
All samples were analyzed using a hybrid linear ion-trap/FT-ICR mass spectrometer (7 T, LTQ FT Ultra, Thermo Scientific, Bremen ... Purification and determination of intact molecular mass by electrospray ionization mass spectrometry of the photosystem II ... Mass spectrometry was performed using a triple quadrupole instrument (AP III+, Applied Biosystems) tuned and calibrated using a ... In addition, the analysis of Psb27 was performed on a hybrid linear ion-trap Fourier-transform orbitrap mass analyzer (LTQ XL ...
Mass Spectrometry, Liquid Chromatography, Electrophoresis), Disease Areas (Oncology, Cardio/Blood, Neurology, Other), Market ... Quadrupolar, Linear and Hybrid Ion Trap Parameters and Summary (Resolution, Mass Accuracy, Sensitivity, Mass Range, Dynamic ... Major Vendor Electrospray Ionization Innovations Summary. Found: , "{{findSearchTermKeyBySig(k)}}" appears {{v}} times.. ... Proteomics Research Mass Spectrometry Market (Orbitraps, Ion Traps, TOF, Q-TOF, Triple Quadrupole, FT-MS) (2015/2020) ($ ...
Mass Spectrometry *Triple Quadrupole *Time-of-Flight *Ion Trap / Orbitrap *Ion Sources *Ion Activation *Reagents * ... Table 3-5: Quadrupolar, Linear and Hybrid Ion Trap Parameters and Summary(Resolution, Mass Accuracy, Sensitivity, Mass Range, ... Table 3-7: Major Vendor Electrospray Ionization Innovations Summary *Table 3-8: Surface Analysis Ionization Technique ... Table 1-2: Proteomics Research Mass Spectrometry Market (Orbitraps, Ion Traps,TOF, Q-TOF, Triple Quadrupole, FT-MS) (2015/2020 ...
MDS Sciex 4000 Q-Trap hybrid triple quadrupole linear ion trap mass spectrometer. The instrument is equipped with an ABI Turbo ... V electrospray ionization ion (ESI) source and interfaced with a Shimadzu multi pump HPLC system equipped with a column oven ... Ms Sunkara has a background in analytical chemistry with additional experience in biomedical mass spectrometry gained with a ... This goal has been accomplished by use of two complementary technologies: HPLC Tandem mass spectrometry and multiplex ...
... using hybrid triple quadrupole/linear ion trap mass spectrometers (AB SCIEX 3200 QTRAP; AB SCIEX, Framingham, MA). The mass ... Mass spectrometric detection was accomplished by using positive ionization with electrospray ionization sources and scanning in ... The concentrations of DEX in the vitreous humor were determined by liquid chromatography/mass spectrometry/mass spectrometry ( ... humor was immediately aspirated and the DEX level was measured by liquid chromatography/mass spectrometry/mass spectrometry. ...
The Orbitrap analyzer can be interfaced to a linear ion trap (LTQ Orbitrap family of instruments), quadrupole mass filter (Q ... By processing data in a manner similar to that used in Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), ... of the technology was carried out using the direct injection of ions from an external laser desorption and ionization ion ... of injection works well with pulsed sources such as MALDI but cannot be interfaced to continuous ion sources like electrospray ...
... by Yersinia pseudotuberculosis using liquid chromatography coupled to hybrid quadrupole-linear ion trap mass spectrometry ... liquid chromatography/negative ion electrospray ionisation tandem mass spectrometry Rapid Communications in Mass Spectrometry. ... including tandem quadrupole LC-MS, LC quadrupole linear ion trap mass spectrometry, quadrupole-time-of-flight mass spectrometry ... robustum hairy roots by liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry JOURNAL ...
... molecules by Poisson detection mass spectrometry (MS). TIL from the patients recognized 5/181 and 3/49 of the predicted ... molecules by Poisson detection mass spectrometry (MS). TIL from the patients recognized 5/181 and 3/49 of the predicted ... complex I-bound peptides using a probabilistic measure and nanospray MS3 on a hybrid quadrupole-linear ion trap. Anal Chem. ( ... With mass spectrometry 3/136 (KADA, not all peptides could be analyzed) and 1*/38 (ANRU, not all peptides could be analyzed) of ...
... through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry ... 8. Rapid resolution liquid chromatography-electrospray ionisation tandem mass spectrometry method for identification of ... An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step ... coupled with diode array and accurate mass spectrometry detection using electrospray ionisation (DAD/ESI-am-MS). Instrumental ...
  • Ions of a particular mass-to-charge ratio (precursor ions) are selected and fragment ions (product ions) are created by collision-induced dissociation, ion-molecule reaction, photodissociation, or other process. (wikipedia.org)
  • The product ions found in these spectra share many common peaks as those found in other publications and repository online MS/MS spectral databases, such as mzCloud , an online MS/MS spectral database. (highchem.com)
  • For example, selected reaction monitoring (SRM) 1 uses quadrupole mass analyzers to filter specific precursor and fragment ions produced by collision-induced dissociation (CID) ( 6 ⇓ ⇓ - 9 ). (mcponline.org)
  • To overcome these limitations, parallel reaction monitoring (PRM) has been developed by leveraging high-resolution Orbitrap mass analyzers to improve assay specificity because of monitoring fragment ions with parts per million (ppm) mass accuracy ( 13 , 14 ). (mcponline.org)
  • Compared with the 3D QIT, this offers certain performance advantages, including less susceptibility to space charge effects and the ability to display CID fragment ions throughout the entire m/z range. (12dakot.com)
  • Grouping all precursor ions with a common OzID neutral loss enables straightforward classification of the lipidome by unsaturation position (with respect to the methyl terminus). (springer.com)
  • Mode of data collection in tandem mass spectrometry in which a fixed number of precursor ions whose m/z values were recorded in a survey scan are selected using predetermined rules and are subjected to a second stage of mass selection in an MS/MS analysis. (psu.edu)
  • 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)
  • Waters recently introduced the Rapid Evaporative Ionization Mass Spectrometry™ ( REIMS™ ) Research System with iKnife™ Sampling, a method of ionizing nontraditional samples under ambient conditions that wouldn't be appropriate for normal sample preparation or chromatographic separation protocols. (biocompare.com)
  • Another aspect of the invention provides the ability to form potential wells, utilizing a segmented rod set configuration, so as to trap and hold ions after separation based on mobility characteristics. (google.es)
  • The liquid chromatographs (located in Malott Hall) are arranged in an instrument room such that the Waters Qtof Premier (Qtof) or Quattro ultima "triple" quadrupole (QQQ) can be interfaced to micro, capillary or ultra-pressure LC by choosing the Water 2695, CapLC or acquity classic UPLC. (ku.edu)
  • The ion-beam compressor technology in Agilent's TOF and qTOF analyzers helps concentrate ions for better transmission to the detector. (biocompare.com)
  • Ziel dieser Arbeit war die Aufklärung unterschiedlicher Ionisationsmethoden (Resonanz-verstärkte Mehrphotonenionisation - REMPI, Elektrosprayionisation - ESI, chemische Ionisation bei Atmosphärendruck - APCI) in der Ionenmobilitäts (IM)-Spektrometrie. (dissertation.com)
  • Ions generated by API (APCI, ESI, nanoESI) are collected in the LTQ XL followed by axial ejection to the C-shaped storage trap which is used to store and collisionally cool ions before injection into the orbitral trap. (uochb.cz)
  • ESI, nano-ESI and APCI ion sources are available. (uochb.cz)
  • Similar to the precursor-ion scan, this technique is also useful in the selective identification of closely related class of compounds in a mixture. (wikipedia.org)
  • Scientists across many disciplines use mass spectrometry to identify unknown compounds, elucidate structures and quantify components in a sample, whether it is solid, liquid, or gas. (selectscience.net)
  • The correct formulas were retrieved as top hit at 80-99% probability when assuming data acquisition with complete resolution of unique compounds and 5% absolute isotope ratio deviation and 3 ppm mass accuracy. (biomedcentral.com)
  • The nanoBooster, which does enrich the carrier gas with organic solvent vapor, can increase the ionization efficiency for a wide range of compounds. (biocompare.com)
  • Until relatively recently mass spectrometry was restricted in its use to determining the molecular weight of relatively volatile compounds. (biomedcentral.com)
  • Measured concentrations and mass flows of phenolic endocrine disruptors, particularly nonylphenolic compounds, bisphenol A and parabens in municipal wastewater effluents and in the Glatt River, Switzerland, show that rain events leading to discharges of untreated wastewater into rivers have a great impact on the riverine mass flows of contaminants. (royalsocietypublishing.org)
  • Neither the Kingdon nor the Knight configurations were reported to produce mass spectra. (wikipedia.org)
  • The major primary and secondary reactions could be characterized and explosive compound ions could be identified and assigned to the peaks in IM spectra. (dissertation.com)
  • The optimal mass range of the spectra is 50 - 2000 Da. (uochb.cz)
  • These studies have shown that 3 p -OHP and 6α-OHP can be distinguished by the collision induced dissociation (CID) patterns in their tandem mass spectra. (springer.com)
  • First, the full scan mass spectra give information on the composition of the solution that is injected, and therefore on the solution-phase stability of the complexes. (uliege.be)
  • Electrospray mass spectrometry was evaluated regarding the reliability of the determination of the stoichiometries and equilibrium association constants from single spectra. (uliege.be)
  • Likewise, the incorporation of high-resolution time-of-flight (TOF) mass analyzers has been used to improve the accuracy of reaction monitoring methods, including their use in data-independent approaches such as SWATH ( 15 , 16 ). (mcponline.org)
  • Different spectroscopic methods (light scattering and fluorescence spectroscopy) permitting a spatial as well as spectral resolution, were used to investigate the release of ions in the electrospray. (dissertation.com)
  • Therefore, on the basis of an assessment of available methods, a novel hybrid method was developed and characterized. (dissertation.com)
  • Machine learning techniques (at this time called Artificial Intelligence), heuristic rules [ 4 ] and other chemometrical methods were combined to investigate nuclear magnetic resonance (NMR) and mass spectrometry (MS) data in order to find the correct structure of unknown chemicals in shorter time than manual investigation of all spectral data. (biomedcentral.com)
  • With these two oligosaccharides infused together, MS 2 of their doubly-sodiated molecular ions at m/z 1169.5 (Figure 2) produces fragments corresponding to both N 5 H 5 -I and N 5 H 5 -II, with each oligosaccharide effectively contaminating the spectrum of the other. (bio-medicine.org)
  • Nanospray, another ion-generating process, is useful for researchers using small sample volumes, as in the case of precious or rare sample material. (biocompare.com)
  • An integrated approach utilizing artificial neural networks and SELDI mass spectrometry for the classification of human tumours and rapid identification of potential biomarkers", Bioinformatics, 2002, vol. 18, pp. 395-404. (patentgenius.com)
  • Predicting time to prostate cancer recurrence based on joint models for non-linear longitudinal biomarkers and event time outcomes", Statistics in Medicine, 2002, vol. 21, pp. 3897-3911. (patentgenius.com)
  • Screening, full-scan ( m/z 40-600) DI/EI-MS analysis of crude tear extracts showed that diagnostic ions located in the mass range m/z 350 to 400 were those derived from free cholesterol, with no contribution from cholesterol esters. (arvojournals.org)
  • To tackle this grand challenge, this paper presents a novel approach, based on electrochemistry (EC) combined with mass spectrometry (MS). In this approach, a target compound is allowed to undergo electrochemical oxidation and then subject to MS analysis. (readbyqxmd.com)
  • Trapping instruments can perform multiple steps of analysis, which is sometimes referred to as MSn (MS to the n). (wikipedia.org)
  • This instrument is capable of automated liquid and headspace gas sampling, and solid phase microextractions (SPME) for MS analysis with electron or chemical ionization (EI, CI). (ucla.edu)
  • f. removing daughter ions that match, wherein said pattern match candidate can be used directly or used for further analysis in data mining. (google.com)
  • at least one mass analysis section, providing a final mass analysis section, for receiving ions from the RF ion guide and for separating ions based on differing mass-to-charge characteristics. (google.es)
  • One that is making the life of the mass spectrometrist far easier by removing the need for sample preparation, speeding up analysis and allowing ionisation to take place in the open air. (chemistryworld.com)
  • Removal of detergents and salts prior to MS analysis reduces both ion suppression and spectral interferences resulting in improved data quality. (planetorbitrap.com)
  • a multipole rod set comprising a plurality of rods arranged around the axis thereof, and a conductive cylinder with the axis of the ion mobility section extending down the axis of the cylinder. (google.es)
  • Ion mobility distributions of 3 p -OHP and 6α-OHP indicate that hydroxylation of PTX at different sites yields distinct gas phase structures. (springer.com)
  • In the present study, using electrospray ionization ion mobility mass spectrometry (ESI-IM-MS) and low-energy CID, we have characterized PTX and its metabolites on the basis of their gas-phase structural properties. (springer.com)