Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The pressure due to the weight of fluid.
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)
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.
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)
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.
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.
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.
Chromatographic techniques in which the mobile phase is a liquid.
The rate dynamics in chemical or physical systems.
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.
The sum of the weight of all the atoms in a molecule.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
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.
A syndrome related to increased atmospheric pressure and characterized by tremors, nausea, dizziness, decreased motor and mental performance, and SEIZURES. This condition may occur in those who dive deeply (c. 1000 ft) usually while breathing a mixture of oxygen and helium. The condition is associated with a neuroexcitatory effect of helium.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A plant genus of the LAMIACEAE family.
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
The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
Enzymes catalyzing the oxidation of arachidonic acid to hydroperoxyarachidonates. These products are then rapidly converted by a peroxidase to hydroxyeicosatetraenoic acids. The positional specificity of the enzyme reaction varies from tissue to tissue. The final lipoxygenase pathway leads to the leukotrienes. EC 1.13.11.- .
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.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
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)
An enzyme of the oxidoreductase class primarily found in PLANTS. It catalyzes reactions between linoleate and other fatty acids and oxygen to form hydroperoxy-fatty acid derivatives.
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).
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
Eicosatetraenoic acids substituted in any position by one or more hydroxy groups. They are important intermediates in a series of biosynthetic processes leading from arachidonic acid to a number of biologically active compounds such as prostaglandins, thromboxanes, and leukotrienes.
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.
Cyanogen bromide (CNBr). A compound used in molecular biology to digest some proteins and as a coupling reagent for phosphoroamidate or pyrophosphate internucleotide bonds in DNA duplexes.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
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 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.
Elements of limited time intervals, contributing to particular results or situations.
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)
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)
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)
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.
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.
The force per unit area that the air exerts on any surface in contact with it. Primarily used for articles pertaining to air pressure within a closed environment.
A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a "slow-reacting substance of ANAPHYLAXIS" released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed)
A biologically active tridecapeptide isolated from the hypothalamus. It has been shown to induce hypotension in the rat, to stimulate contraction of guinea pig ileum and rat uterus, and to cause relaxation of rat duodenum. There is also evidence that it acts as both a peripheral and a central nervous system neurotransmitter.
A lipoxygenase metabolite of ARACHIDONIC ACID. It is a highly selective ligand used to label mu-opioid receptors in both membranes and tissue sections. The 12-S-HETE analog has been reported to augment tumor cell metastatic potential through activation of protein kinase C. (J Pharmacol Exp Ther 1995; 274(3):1545-51; J Natl Cancer Inst 1994; 86(15):1145-51)
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)
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.
The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.
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)
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.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Salts that melt below 100 C. Their low VOLATILIZATION can be an advantage over volatile organic solvents.
Techniques for measuring blood pressure.
Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
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.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
The process of cleaving a chemical compound by the addition of a molecule of water.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Proteins prepared by recombinant DNA technology.
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.
Established cell cultures that have the potential to propagate indefinitely.
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 subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.
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 domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.
Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
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.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
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).
Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.
Transducers that are activated by pressure changes, e.g., blood pressure.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Pressure within the cranial cavity. It is influenced by brain mass, the circulatory system, CSF dynamics, and skull rigidity.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The pressure of the fluids in the eye.
An essential amino acid. It is often added to animal feed.
Method in which repeated blood pressure readings are made while the patient undergoes normal daily activities. It allows quantitative analysis of the high blood pressure load over time, can help distinguish between types of HYPERTENSION, and can assess the effectiveness of antihypertensive therapy.
Materials in intermediate state between solid and liquid.
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.
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.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
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).
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.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
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 interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that are common in the marine environment and on the surfaces and in the intestinal contents of marine animals. Some species are bioluminescent and are found as symbionts in specialized luminous organs of fish.
A type of ion exchange chromatography using diethylaminoethyl cellulose (DEAE-CELLULOSE) as a positively charged resin. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Peptides composed of between two and twelve amino acids.
The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.
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.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The blood pressure in the ARTERIES. It is commonly measured with a SPHYGMOMANOMETER on the upper arm which represents the arterial pressure in the BRACHIAL ARTERY.
The pressure within a CARDIAC VENTRICLE. Ventricular pressure waveforms can be measured in the beating heart by catheterization or estimated using imaging techniques (e.g., DOPPLER ECHOCARDIOGRAPHY). The information is useful in evaluating the function of the MYOCARDIUM; CARDIAC VALVES; and PERICARDIUM, particularly with simultaneous measurement of other (e.g., aortic or atrial) pressures.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
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.
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 seventh planet in order from the sun. It is one of the five outer planets of the solar system. It has five known natural satellites.
A method of gel filtration chromatography using agarose, the non-ionic component of agar, for the separation of compounds with molecular weights up to several million.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
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)
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
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.
Measurement of the pressure or tension of liquids or gases with a manometer.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Procedures or techniques used to keep food from spoiling.
A modification of the freeze-drying method in which the ice within the frozen tissue is replaced by alcohol or other solvent at a very low temperature.
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 eighth planet in order from the sun. It is one of the five outer planets of the solar system. Its two natural satellites are Nereid and Triton.
The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
The blood pressure as recorded after wedging a CATHETER in a small PULMONARY ARTERY; believed to reflect the PRESSURE in the pulmonary CAPILLARIES.
Liquids transforming into solids by the removal of heat.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
A centrally acting muscle relaxant with a short duration of action.
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)
A rare metal element with a blue-gray appearance and atomic symbol Ge, atomic number 32, and atomic weight 72.63.
A CHROMATOGRAPHY method using supercritical fluid, usually carbon dioxide under very high pressure (around 73 atmospheres or 1070 psi at room temperature) as the mobile phase. Other solvents are sometimes added as modifiers. This is used both for analytical (SFC) and extraction (SFE) purposes.
The chemical and physical integrity of a pharmaceutical product.
The pressure required to prevent the passage of solvent through a semipermeable membrane that separates a pure solvent from a solution of the solvent and solute or that separates different concentrations of a solution. It is proportional to the osmolality of the solution.
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)
A series of steps taken in order to conduct research.
Devices for accelerating protons or electrons in closed orbits where the accelerating voltage and magnetic field strength varies (the accelerating voltage is held constant for electrons) in order to keep the orbit radius constant.
An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).
Quanta of acoustic energy which move at the speed of sound.
Measurement of the intensity and quality of fluorescence.
Period of contraction of the HEART, especially of the HEART VENTRICLES.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
Any aspect of the operations in the preparation, processing, transport, storage, packaging, wrapping, exposure for sale, service, or delivery of food.
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.
The therapeutic intermittent administration of oxygen in a chamber at greater than sea-level atmospheric pressures (three atmospheres). It is considered effective treatment for air and gas embolisms, smoke inhalation, acute carbon monoxide poisoning, caisson disease, clostridial gangrene, etc. (From Segen, Dictionary of Modern Medicine, 1992). The list of treatment modalities includes stroke.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Creation and development of bodies within solar systems, includes study of early planetary geology.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The rhythmical expansion and contraction of an ARTERY produced by waves of pressure caused by the ejection of BLOOD from the left ventricle of the HEART as it contracts.
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.
Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.
The branch of biology dealing with the effect of light on organisms.
A change of a substance from one form or state to another.
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
Inorganic compounds that contain calcium as an integral part of the molecule.
A ubiquitous sodium salt that is commonly used to season food.
A genus of zygomycetous fungi in the family Mucoraceae, order MUCORALES, forming mycelia having a metallic sheen. It has been used for research on phototropism.
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.
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)
Organic and inorganic compounds that contain iron as an integral part of the molecule.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
Manometric pressure of the CEREBROSPINAL FLUID as measured by lumbar, cerebroventricular, or cisternal puncture. Within the cranial cavity it is called INTRACRANIAL PRESSURE.
The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.
A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
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.
Methods of creating machines and devices.
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)
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)
Proteins found in any species of bacterium.

An investigation into the binding of the carcinogen 15,16-dihydro-11-methylcyclopenta[a]phenanthren-17-one to DNA in vitro. (1/27865)

After metabolic activation the carcinogen 15,16-dihydro-11-[3H]methylcyclopenta[a]phenanthren-17-one binds to DNA in vitro, and this binding is prevented by 7,8-benzoflavone. Radioactivity cannot be removed from the DNA with organic solvents or by chromatography on Sephadex G-50, even after heat denaturation of the DNA. Enzymatic hydrolysis yields radioactive fractions, which elute from a column of Sephadex LH-20 immediately after the natural nucleosides. At least two species of reactive metabolites are involved in this bending, those with a half-life of a few hr and others with greater stability. After extraction from the aqueous incubation mixture, they could be detected in discrete polar fractions from separations of the complex metabolite mixture by high-pressure liquid chromatography. Their ability to bind to DNA decreased with time at ambient temperature, and they were rapidly deactivated by acid. 7,8-Benzolflavone acted by suppressing the formation of polar metabolites derived from enzymatic oxidation of the aromatic double bonds. The inhibitor had no effect on the enzymes hydroxylating saturated carbon; hence it is unlikely that metabolism of the methyl group is important in conversion of this carcinogen to its proximate form, although the presence of the 11-methyl group is essential for carcinogenic activity in this series.  (+info)

The direct spectrophotometric observation of benzo(a)pyrene phenol formation by liver microsomes. (2/27865)

Optical spectral repetitive scan analysis during the oxidative metabolism of benzo(a)pyrene by liver microsomal suspensions reveals the time-dependent formation of an intermediate(s) of which the visible spectra resemble those of several benzo(a)pyrene phenols. Liver microsomes from 3-methylcholanthrene-treated rats showed a greater rate of formation of the phenols than did microsomes from control animals; the rate of formation catalyzed by liver microsomes from phenobarbital-pretreated rats was intermediate. When 3-hydroxybenzo(a)pyrene was used as a standard for comparison of activity, the rates of formation of phenols were compared when measured by fluorometric, spectrophotometric, or high-pressure liquid chromatographic analytical techniques. An epoxide hydrase inhibitor, 1,1,1-trichloropropene-2,3-oxide, enhanced phenol formation regardless of the source of liver microsomes, and 7,8-benzoflavone inhibited control and 3-methylcholanthrene-induced microsomal metabolism of benzo(a)pyrene, 7,8-Benzoflavone did not effect benzo(a)pyrene metabolism by liver microsomes from phenobarbital-pretreated rats. The effect of inhibitors on the spectrophotometric assay correlates well with the results obtained from benzo(a)pyrene metabolite analysis using high-pressure liquid chromatography.  (+info)

A novel H2A/H4 nucleosomal histone acetyltransferase in Tetrahymena thermophila. (3/27865)

Recently, we reported the identification of a 55-kDa polypeptide (p55) from Tetrahymena macronuclei as a catalytic subunit of a transcription-associated histone acetyltransferase (HAT A). Extensive homology between p55 and Gcn5p, a component of the SAGA and ADA transcriptional coactivator complexes in budding yeast, suggests an immediate link between the regulation of chromatin structure and transcriptional output. Here we report the characterization of a second transcription-associated HAT activity from Tetrahymena macronuclei. This novel activity is distinct from complexes containing p55 and putative ciliate SAGA and ADA components and shares several characteristics with NuA4 (for nucleosomal H2A/H4), a 1.8-MDa, Gcn5p-independent HAT complex recently described in yeast. A key feature of both the NuA4 and Tetrahymena activities is their acetylation site specificity for lysines 5, 8, 12, and 16 of H4 and lysines 5 and 9 of H2A in nucleosomal substrates, patterns that are distinct from those of known Gcn5p family members. Moreover, like NuA4, the Tetrahymena activity is capable of activating transcription from nucleosomal templates in vitro in an acetyl coenzyme A-dependent fashion. Unlike NuA4, however, sucrose gradient analyses of the ciliate enzyme, following sequential denaturation and renaturation, estimate the molecular size of the catalytically active subunit to be approximately 80 kDa, consistent with the notion that a single polypeptide or a stable subcomplex is sufficient for this H2A/H4 nucleosomal HAT activity. Together, these data document the importance of this novel HAT activity for transcriptional activation from chromatin templates and suggest that a second catalytic HAT subunit, in addition to p55/Gcn5p, is conserved between yeast and Tetrahymena.  (+info)

Isolation and complete covalent structure of liver microsomal paraoxonase. (4/27865)

Paraoxonase (PON1) is a serum esterase exclusively associated with high-density lipoproteins; it might confer protection against coronary artery disease by destroying pro-inflammatory oxidized lipids in oxidized low-density lipoproteins. Here I show that rabbit liver microsomes contain a PON analogue (MsPON) and report the isolation and complete covalent structure of MsPON. In detergent-solubilized microsomes, MsPON co-purifies with the microsomal triacylglycerol transfer protein (MTP) complex. MsPON was separated from the complex and purified to homogeneity under non-denaturing conditions. Automated sequence analysis of intact MsPON and peptides obtained from enzymic and chemical cleavages led to the elucidation of the complete covalent structure of MsPON. The protein is a single polypeptide consisting of 350 residues. The sequence of rabbit liver microsomal MsPON is 60% identical with that of rabbit serum PON1, and 84% identical with the sequence predicted by a human cDNA of unknown function, designated PON3. MsPON has a hydrophobic segment at the N-terminus that might serve to anchor the protein to the microsomal membrane or to the MTP complex. Unlike in the serum enzyme, two potential N-glycan acceptor sites in MsPON are not glycosylated. An absence of N-glycans was also indicated in the rabbit liver MTP. MsPON has a single free cysteine residue at position 38 and a disulphide bond between Cys-279 and Cys-348. The microsomal enzyme lacks three residues at the N-terminus that are present in the serum protein. MsPON lacks four residues at the C-terminus that are present in the rabbit serum protein but absent from human serum PON1. On the basis of the observation that MsPON displays a high degree of similarity with serum PON1, it is proposed that MsPON might have a function related to that of PON1 in serum high-density lipoprotein complexes.  (+info)

Simultaneous antisense inhibition of two starch-synthase isoforms in potato tubers leads to accumulation of grossly modified amylopectin. (5/27865)

A chimaeric antisense construct was used to reduce the activities of the two major starch-synthase isoforms in potato tubers simultaneously. A range of reductions in total starch-synthase activities were found in the resulting transgenic plants, up to a maximum of 90% inhibition. The reduction in starch-synthase activity had a profound effect on the starch granules, which became extremely distorted in appearance compared with the control lines. Analysis of the starch indicated that the amounts produced in the tubers, and the amylose content of the starch, were not affected by the reduction in activity. In order to understand why the starch granules were distorted, amylopectin was isolated and the constituent chain lengths analysed. This indicated that the amylopectin was very different to that of the control. It contained more chains of fewer than 15 glucose units in length, and fewer of between 15 and 80 glucose units. In addition, the amylopectin contained more very long chains. Amylopectin from plants repressed in just one of the activities of the two starch-synthase isoforms, which we have reported upon previously, were also analysed. Using a technique different to that used previously we show that both isoforms also affect the amylopectin, but in a way that is different to when both isoforms are repressed together.  (+info)

Purinogen is not an endogenous substrate used in endothelial cells during substrate deprivation. (6/27865)

Porcine aortic endothelial cells (PAEC) are known to be metabolically robust. They are capable of surviving extended periods of complete lack of exogenous substrate, and purine release has been shown to be significantly up-regulated. The endogenous substrates used during substrate deprivation, as well as the sources responsible for the increased purine release, have not been completely identified. We tested the possibility that a phosphoglyceroyl-ATP-containing polymer, purinogen, might support PAEC hibernation induced by lack of exogenous substrate. This involved isolation of the acid-insoluble fraction of PAEC, which was presumed to contain purinogen, and analysis by HPLC and 31P NMR. No evidence supporting the presence of triphosphate-containing compounds (purinogen) was found. Similar results were obtained in the rat heart. The majority of the products in the acid-insoluble, alkaline-treated fraction were identified as RNA degradation products (2'- and 3'-nucleoside monophosphates). A [14C]adenosine labelling experiment showed that incorporation of adenosine into the acid-insoluble fraction was almost completely prevented after inhibition of RNA synthesis with actinomycin D. Furthermore, RNA isolated from PAEC and subsequently treated with alkali showed a profile that was almost identical with the HPLC profile of the acid-insoluble fraction. Finally, substrate-free incubation of the cells did not quantitatively or qualitatively influence the distribution of acid-insoluble derivatives. We conclude that PAEC survival during the absence of exogenous substrate is not supported by purinogen but rather by some other, yet-to-be-identified, endogenous substrate.  (+info)

Accumulation of astaxanthin all-E, 9Z and 13Z geometrical isomers and 3 and 3' RS optical isomers in rainbow trout (Oncorhynchus mykiss) is selective. (7/27865)

Concentrations of all-E-, 9Z- and 13Z- geometrical and (3R,3'R), (3R, 3'S) and (3S,3'S) optical isomers of astaxanthin were determined in rainbow trout liver, gut tissues, kidney, skin and blood plasma to evaluate their body distribution. Two cold-pelleted diets containing predominantly all-E-astaxanthin (36.9 mg/kg astaxanthin, 97% all-E-, 0.4% 9Z-, 1.5% 13Z-astaxanthin, and 1.1% other isomers, respectively) or a mixture of all-E- and Z-astaxanthins (35.4 mg/kg astaxanthin, 64% all-E-, 18.7% 9Z-, 12.3% 13Z-astaxanthin, and 2.0% other isomers, respectively), were fed to duplicate groups of trout for 69 d. Individual E/Z isomers were identified by VIS- and 1H-NMR-spectrometry, and quantified by high-performance liquid chromatography. Significantly higher total carotenoid concentration was observed in plasma of trout fed diets with all-E-astaxanthin (P < 0.05). The relative E/Z-isomer concentrations of plasma, skin and kidney were not significantly different among groups, whereas all-E-astaxanthin was higher in intestinal tissues and 13Z-astaxanthin was lower in liver of trout fed all-E-astaxanthin (P < 0.05). The relative amount of hepatic 13Z-astaxanthin (39-49% of total astaxanthin) was higher than in all other samples (P < 0.05). Synthetic, optically inactive astaxanthin was used in all experiments, and the determined dietary ratio between the 3R,3'R:3R, 3'S (meso):3S,3'S optical isomers was 25.3:49.6:25.1. The distribution of R/S-astaxanthin isomers in feces, blood, liver and fillet was similar to that in the diets. The ratio between (3S,3'S)- and (3R,3'R)-astaxanthin in the skin and posterior kidney was ca. 2:1 and 3:1, respectively, regardless of dietary E/Z-astaxanthin composition. The results show that geometrical and optical isomers of astaxanthin are distributed selectively in different tissues of rainbow trout.  (+info)

Daidzein and genistein glucuronides in vitro are weakly estrogenic and activate human natural killer cells at nutritionally relevant concentrations. (8/27865)

Daidzein and genistein glucuronides (DG and GG), major isoflavone metabolites, may be partly responsible for biological effects of isoflavones, such as estrogen receptor binding and natural killer cell (NK) activation or inhibition. DG and GG were synthesized using 3-methylcholanthrene-induced rat liver microsomes. The Km and Vmax for daidzein and genistein were 9.0 and 7.7 micromol/L, and 0.7 and 1.6 micromol/(mg protein. min), respectively. The absence of ultraviolet absorbance maxima shifts in the presence of sodium acetate confirmed that the synthesized products were 7-O-glucuronides. DG and GG were further purified by a Sephadex LH-20 column. DG and GG competed with the binding of 17beta-(3H) estradiol to estrogen receptors of B6D2F1 mouse uterine cytosol. The concentrations required for 50% displacement of 17beta-(3H) estradiol (CB50) were: 17beta-estradiol, 1.34 nmol/L; diethylstilbestrol, 1.46 nmol/L; daidzein, 1.6 micromol/L; DG, 14.7 micromol/L; genistein, 0.154 micromol/L; GG, 7.27 micromol/L. In human peripheral blood NK cells, genistein at <0.5 micromol/L and DG and GG at 0.1-10 micromol/L enhanced NK cell-mediated K562 cancer cell killing significantly (P < 0.05). At > 0.5 micromol/L, genistein inhibited NK cytotoxicity significantly (P < 0.05). The glucuronides only inhibited NK cytotoxicity at 50 micromol/L. Isoflavones, and especially the isoflavone glucuronides, enhanced activation of NK cells by interleukin-2 (IL-2), additively. At physiological concentrations, DG and GG were weakly estrogenic, and they activated human NK cells in nutritionally relevant concentrations in vitro, probably at a site different from IL-2 action.  (+info)

TY - JOUR. T1 - Determination of lamotrigine and feibamate in pediatric plasma samples by reverse phase high-performance liquid chromatography. AU - Kumarjain, S.. AU - Vasantharaju, S.G.. AU - Shetty, R.. AU - Bejugam, N.. AU - Sajjad Hussen, S.. AU - Bhat, K.. N1 - cited By 0. PY - 2013. Y1 - 2013. M3 - Article. VL - 47. SP - 160. EP - 167. JO - Indian Journal of Pharmaceutical Education and Research. JF - Indian Journal of Pharmaceutical Education and Research. SN - 0019-5464. IS - 2. ER - ...
An Improved High Performance Liquid Chromatographic Method for Tryptophan Analysis in Rat Brain Administrated by Seaweed Abstract.
Indirect evidence has implicated a role for central angiotensin II in blood pressure control. To answer directly the question of whether angiotensin II exists in the brain, independent of blood-borne angiotensin, and to quantify the amounts in different parts of the central nervous system, a sensitive radioimmunoassay was used to measure extracts of male adult rat brain hypothalamus and cortex after purification with high pressure liquid chromatography with a high recovery. The fractions coeluted with authentic angiotensin. Rats were nephrectomized bilaterally, and 24 hours later the brains were extracted in acetic acid and boiled. SepPak C-18 purification preceded reverse phase high pressure liquid chromatography. High pressure liquid chromatography revealed two peaks, one which comigrated precisely with [Ile5] angiotensin II, and another smaller peak which overlapped with [Ile5] angiotensin III. The highest levels were found in the hypothalamus (125 pg/g tissue), pituitary (190 pg/g tissue), ...
The formation of 7-hydroxywarfarin in incubations of (S)-warfarin with human liver microsomes reflects their cytochrome P-4502C9 activity. This paper describes a rapid high-performance liquid chromatographic method for the determination of 7-hydroxywarfarin with high sensitivity, selectivity, and a …
TY - JOUR. T1 - Linear and quadratic relationships between retention and organic modifier content in eluent in Reversed Phase High-Performance Liquid Chromatography: A systematic comparative statistical study. AU - Baczek, T.. AU - Markuszewski, M.. AU - Kaliszan, R.. AU - Straten, van, M.A.. AU - Claessens, H.A.. PY - 2000. Y1 - 2000. N2 - Statistical evaluation of linear and quadratic models of chromatographic retention was performed. The relationships describing retention were derived for a set of 23 carefully selected test analytes chromatographed on 18 HPLC columns using methanol-water or acetonitrile- water solutions as mobile phase. It was ascertained whether the square term in the quadratic model improves the description of chromatographic retention in a statistically significant manner. It was also checked whether the retention data extrapolated to a hypothetical neat water eluent (log kw) obtained with the two models and the two organic modifiers are equivalent or should be considered ...
TY - JOUR. T1 - Determination of transdermal sildenafil in nude mouse skin by reversed-phase high-performance liquid chromatography. AU - Liaw, Jiahorng. AU - Chang, Ting Wei. PY - 2001/12/25. Y1 - 2001/12/25. N2 - A simple and sensitive high-performance liquid chromatographic method was developed for the determination of sildenafil transdermal permeation of nude mouse skin. A reversed-phase column with UV detection at 224 nm was used for chromatographic separation. The mobile phase consisted of 32% acetonitrile with 0.2% phosphoric acid in water at pH 5.3 adjusted with 10 M NaOH with the flow-rate set at 1.0 ml/min. The limit of quantitation achieved was 5 ng/ml, and the calibration curve showed good linearity over the concentration range of 5-500 ng/ml. The relative standard deviations of within- and between-day analyses were all within 15%. Sildenafil was found to be stable between pH 3 and 12 during 24-h incubation with skin. After transdermal administration of 15.8 μg/ml of sildenafil to ...
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A new high-performance liquid chromatographic method was developed for quantification of midazolam in plasma samples from intensive care unit patients on long-term intravenous infusion of this benzodiazepine. Plasma samples (0.5 ml) were mixed with 1 microgram flurazepam (internal standard), alkalinized with 2.5 N NaOH, and extracted with toluene. The organic phase was evaporated to dryness, and the residue was dissolved in the mobile phase (acetonitrile/0.05 M phosphate buffer pH 4.5) and injected into the analytical column (C18 Nova-Pak 3.9 x 150 mm, 4 microns, maintained at room temperature; mobile phase flow rate: 1.2 ml/minute). The eluate was monitored at 207 nm, which reduced the risk of interferences from concurrent medications. Retention times of flurazepam, 1-hydroxymidazolam (an active metabolite) and midazolam were approximately 4.5, 6.1 and 13.5 minutes, respectively. The assay was linear over the range 100 to 3000 ng/ml. The coefficients of variation of the within-day and ...
P.L. Desbène, F.I. Portet, G.J. Goussot. Quantitative trace analysis of surfactant mixtures by reversed-phase high-performance liquid chromatography with refractometric detection. Journal of Chromatography A, Elsevier, 1996, 730 (1-2), pp.209 - 218. ⟨10.1016/0021-9673(95)01087-4⟩. ⟨hal-01936813⟩ ...
A simple, sensitive and reproducible high-performance liquid chromatography (HPLC) method was developed for the determination of terazosin in human plasma. The method involves a one-step single solvent extraction procedure using dichloromethane with a 0.25 ml plasma sample. Recovery values were all greater than 90% over the concentration range 0.25-100 ng/ml. Terazosin was found to adsorb to glass or plastic tubes, but this could be circumvented by using disposable plastic tubes. Also, rinsing the injector port with methanol after each injection helped to prevent any carry-over effect. The internal standard, prazosin, did not exhibit this problem. The method has a quantification limit of 0.25 ng/ml. The within- and between-day coefficient of variation and accuracy values were all less than 7% over the concentration range 0.25-100 ng/ml and hence the method is suitable for use in pharmacokinetic studies of terazosin.
The High Performance Liquid Chromatography HPLC is a really important technique employed in analytical chemistry and can be used to separate a mixture component, identify and measure all the elements found in the mix. The ratio between the concentration of a chemical being analyzed into the response of this sensor to that compound is commonly referred as the response element. This is because each element is known to interact differently with the adsorbent material hence resulting to some diverse flow rates of these components thereby easing the separation of the stated components of a mixture. This technique has hence found immense use in medical units as well as in manufacturing plants for a variety of uses. The response factor is obtained by dividing the concentration by the summit area. For example when a solution comprising three materials is being handled, it is easier to separate these elements by immersing it in an adsorbent material and then injecting it into the HPLC.. It is expected ...
The general aim of this thesis was to evaluate a newly designed and constructed miniaturized rotating disk apparatus for in vitro dissolution rate measurements of different drug substances from all of the classes in the Biopharmaceutical Classification System (BCS). The new equipment is based on a low volume flow-through cell of Plexiglas, a gold plated magnetic bar and a special designed press. The disk of drug substance (approx. 5 mg) is placed eccentrically in the bar. Rotation speeds were set with a graded magnetic stirrer. An external HPLC pump delivered a continuous flow of aqueous medium to the flow-through cell during dissolution testing.. A reversed phase high-performance liquid chromatography system using diode array detection (RP-HPLC-DAD) was coupled online to the new equipment. The injections from the miniaturized rotating disk outlet into the quantifying HPLC system were controlled by a six-position switching valve. The injection volumes from the valve and the autosampler, used for ...
Determination of free urinary cortisol is a test of choice in the diagnosis of Cushings syndrome. In this study, cortisol was quantified using reversed-phase high-performance liquid chromatography (RP-HPLC) in urine samples previously extracted with ether and using triamcinolone acetonide as internal standard (IS). A BDS-Hypersil-C18® column, water-acetonitrile (72:28; v/v), with a flow rate of 1.0 mL/min and detection at 243 nm were used. This method showed to be both effective and efficient, with sensitivity and linearity ranging from 2.50 to 150 μg/L, and can be used in substitution to the radioimmunoassay technique within this concentration range ...
Oxygenated polyunsaturated fatty acids (PUFAs)play an outstanding role in the physiological and pathological regulation of several biological processes. These oxygenated metabolites can be produced both enzimatically, yielding almost pure enantiomers, and non-enzymatically. The free radical-mediated non-enzymatic oxidation commonly produces racemic mixtures which are used as biomarkers of oxidative stress and tissue damage. The biological activity of oxygenated PUFAs is often associated with only one enantiomer, making it necessary of availing of lipidomics platforms allowing to disclose the role of single enantiomers in health and disease. Polysaccharide-based chiral stationary phases (CSPs) play a dominating part in this setting. As for the cellulose backbone, 4-methylbenzoate derivatives exhibit very high chiral recognition ability towards this class of compounds. Concerning the phenylcarbamate derivatives of cellulose and amylose, the tris(3,5-dimethylphenylcarbamate) variants show the best ...
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We describe a simple, sensitive, and specific high-performance liquid-chromatographic method with ultraviolet detection (256 nm) for the simultaneous analysis of nicotine and cotinine in urine of passive smokers. The analytes are extracted and purified from the complex and impure matrix in two stages; first, by liquid-liquid extraction and followed by solid-phase extraction (C2 column). We used a DB C8 5-microns-particle column (25 x 0.46 cm) and a mobile phase of phosphate-citrate buffer and acetonitrile (91:9 by vol) containing 5 mL of triethylamine and 600 mg of heptanesulfonate per liter, adjusted to pH 4.4, to separate the compounds. Two internal standards (2-phenylimidazole and N-ethylnorcotinine) were used. The detection limit of the HPLC assay was less than 1 microgram/L for both analytes. The average interassay CV for nicotine was 7.6%, for cotinine 6.5%, in the concentration range 0-60 micrograms/L. The mean analytical recovery of nicotine with respect to the internal standard ...
A fully automated and validated 2D online solid-phase extraction (SPE) high-performance liquid chromatographic method was described for the direct simultaneous determination of clenbuterol (CLEN) and doxazosin (DOX) in spiked human plasma samples. Chromatographic separation of the analytes was achieved by column-switching. SPE column packed with restricted access material for depleting matrix and a reversed phase HPLC column for eluting analytes were used with UV detection on 250 nm. A 10 mM acetate buffer (pH: 4) and acetonitrile mixture was used in gradient elution with 1 mL/min flow rate, as mass spectrometry friendly mobile phase. Calibration graphs were prepared for spiked plasma, and good linearity was achieved over a dynamic range of 75.0 ng/mL-200.0 mu g/mL for CLEN and 37.5 ng/mL-100.0 mu g/mL for DOX. Detection and quantification limits were 8.47 and 11.94 ng/mL, 25.66 and 36.18 ng/mL for CLEN and DOX, respectively. Online column-switching liquid chromatography technique combines the ...
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This article details the elements used in the method verification for the simultaneous high performance liquid chromatography (HPLC) assay of Pentoxifylline, Mupirocin, Itraconazole, and Fluticasone Propionate in Humco™ Lavare Wound base. The method was proven to be linear over 50%-150% of the nominal concentration of the standards. The method was proven to be accurate over 50%-150%, with 98%-102% recovery of the actives from spiked placeboes over that range. The method was shown to be specific to the analytes listed and precise, yielding acceptable results for system reproducibility and method repeatability. The method, as written, is considered to have been verified.
A novel and generally applicable approach was established to hierarchically identify the bioactive components of a medicinal herb by preparative high-performance liquid chromatography (prep-HPLC) and a selective knock-out strategy. In this study, the targeted components of an herbal medicine were separated and knocked out using prep-HPLC. Subsequently, the contributions of the different target components to the overall effect of the medicinal herb were comparatively evaluated and differentiated by a heat map and a 3D score plot. This approach was successfully applied to investigate the bioactive constituents of safflower. The contributions of 11 components to the overall effect of safflower were as follows: anhydrosafflor yellow B(10)>6-hydroxykaempferol 3,6-di-O-beta-D-glucoside (8 > hydroxysafflor yellow A (3)> kaempferol 3-O-beta-rutinoside (11)> 6-hydroxykaempferol 3-O-beta-rutinoside (9)> 6-hydroxykaempferol 3,6-di-O-beta-D-glucoside-7-O-beta-D-glucuronide (4)> 6-hydroxyapigenin ...
An HPLC method for profiling 13 phytoestrogens and their metabolites using coulometric electrode array detection was developed. Sensitivity of the method was slightly less than that of our GC-MS method, but significantly higher compared to the HPLC methods using diode-array or UV detection. Detectio …
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Background: Losartan potassium is a non-peptide AT1 receptor drug used in the treatment of hypertension. Methods: A simple, rapid, sensitive, and validated isocratic reverse-phase ultra-performance liquid chromatographic (RP-UPLC) method was developed and validated for the determination of losartan potassium (LOS) in bulk drug and tablets. The assay was developed using Waters Acquity BEH C18 (100 mm × 2.1 mm), 1.7-μm column with a mobile phase consisting of a mixture of phosphate buffer (pH 3.2) and acetonitrile (50:50 v/v). Results: An assay with a total run time of only 5 min was developed. The method monitored at 245 nm exhibited linearity over a concentration range of 2.0 to 15.0 μg mL−1 LOS. The limits of detection and quantification (signal-to-noise ratio (S/N) = 10) were found be 0.018 and 0.054 μg mL−1 , respectively. The intraday and interday RSDs were less than 1.0%. The method was validated by the determination of LOS levels in tablets where the percentage on the label claim ...
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GE AKTA fast protein liquid chromatography system is an eagle-i resource of type Fast protein liquid chromatography instrument at Universidad Central del Caribe.
The nearly 50% production capacity increase is in response to growing global demand for purification media from the antibody drug manufacturing industry.. At a cost of approximately ¥5 billion, the Nanyo Complexs Toyopearl production facilities are being expanded. Construction began in October 2016 and is slated for completion in August 2018. Commercial operations at the expanded production facilities are expected to commence in April 2019.. Liquid chromatography separation and purification media are used in the production of biopharmaceutical ingredients. Employing differences in charge, hydrophobicity, specific affinity, and molecular size, these media are designed to separate and purify target components. Given the rapid growth of the market for biopharmaceutical products, in Japan, the United States, and countries in Europe and in China, India, and other emerging nations, these media are in high demand. And Tosoh is committed to meeting that demand.. With its high strength, superior ...
China High Performance Liquid Chromatography, Spectrophotometer, HPLC (RAY-230 HPLC), Find details about China High Performance Liquid Chromatography, Spectrophotometer from High Performance Liquid Chromatography, Spectrophotometer, HPLC (RAY-230 HPLC) - Raylabel Instrument Co., Ltd.
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Background: Elevated circulating levels of BNP as detected on commercial antibody-based assays in heart failure (HF) patients may reflect a mixture of degraded BNP fragments, rather than intact BNP1-32.. Methods: Blood samples from 20 HF patients were collected, immediately centrifuged with plasma promptly aliquoted and frozen at -80°C. In a single thaw, 50uL of 10N HCL was added to 200 uL of plasma, incubated for 10 minutes then centrifuged. 100 uL of supernatant was injected into liquid chromatography mass spectrometry system. On-line extraction and high performance liquid chromatography methods were optimized using Onyx C18 guard and analytical column. Purified synthetic BNP1-32 was then incubated in patient serum and BNP fragments identified. Lastly, a proprietary protocol to inhibit BNP degradation was developed.. Results: The estimated limit of detection of the mass spectrometry method was 0.78 ng/mL and the lower limit of quantitation was 1.5 ng/mL with a good linear relationship ...
Reverse phase High Performance Liquid Chromatography on cyanopropyl-modified silica stationary phase, containing lipophilic and polar moieties, is used. While passing through the column among with the mobile phase the test substance interacts with the stationary phase. As a result of the partitioning between the mobile and stationary phase the test substance is retained. The dual-composition of the stationary phase having polar and non-polar sites allows for interaction of polar and non-polar groups of a molecule in a similar way as it is the case for organic matter in soil or sewage sludge matrices. This enables the relationship between the retention time on the column and the adsorption coefficient on organic matter to be established. ...
Biodistribution and metabolism of oligonucleotides were determined using a 3H-labeled 20-nucleotide phosphodiester and its phosphorothioate analog. The oligonucleotides were radiolabeled by 3H-methylation of an internal deoxyctidine with HhaI methylase and S- [3H]adenosylmethionine. Biodistribution studies were conducted after intravenous injection of 6 mg/kg (5 muCi) oligonucleotide. Metabolism of the oligonucleotides was determined by paired-ion high performance liquid chromatography. After phosphodiester injections, radiolabel rapidly cleared the blood. Relative initial concentrations were as follows: kidney , blood , heart , liver , lung , spleen. Radiolabel in spleen peaked at 1 hr and remained elevated for 24 hr. At 2 hr the concentration in all organs, except spleen, was equal to that in blood. High performance liquid chromatographic analysis of the kidney, liver, and spleen extracts and urine indicated extremely rapid metabolism to monomer. Results of studies after the injection of ...
A Simple, fast and precise reverse phase high performance liquid chromatographic method is developed for the simultaneous determination of Rosuvastatin Calcium and Fenofibrate. Chromatography was carried out at 400C and Separation of these drugs were performed on BDS C18 column (250 x 4.6 mm, 5 µ) as stationary phase with a mobile phase comprising of Acetonitrile: water (pH adjust to 2.5 with O-Phosphoric Acid) in the ratio of 70:30 (v/v) at a flow rate of 1.5 ml/min and Detection wavelength of Rosuvastatin Calcium and Fenofibrate ware 287nm. The Retention time for Rosuvastatin Calcium and Fenofibrate were 2min and 8.5min respectively. The linearity of Rosuvastatin Calcium and Fenofibrate was in the range of 1 to 5 µg/mL. The recovery was calculated by standard addition method. The proposed method was found to be accurate, precise and rapid for simultaneous determination of Rosuvastatin Calcium and Fenofibrate. It can be used for routine analysis.
TSKgel ODS-100V and TSKgel ODS-100Z columns incorporate the best-in-class surface properties to limit secondary interactions of basic, acidic and chelating compounds. Take advantage of the benefits of high column efficiency and symmetrical peak shapes to reduce your analysis and method development time! The ultra high purity Type B base silica contains negligible amounts of metal ion impurities. Combined with monomeric bonding chemistry, this silica makes the best general purpose Reversed Phase columns suitable for the most demanding separations in quality control as well as in research and development. TSKgel ODS-100V columns have a lower carbon content than ODS-100Z columns, making the bonded phase surface 100% water wettable and the preferred choice to retain polar metabolites.
Academic Journals Database is a universal index of periodical literature covering basic research from all fields of knowledge, and is particularly strong in medical research, humanities and social sciences. Full-text from most of the articles is available. Academic Journals Database contains complete bibliographic citations, precise indexing, and informative abstracts for papers from a wide range of periodicals.
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A simple and precise high performance liquid chromatography method for determination of candesartan cilexetil in their pharmaceutical formulation was developed and validated. The separation was carried out on Cosmosil C18 (250mm X 4.6, 5μ) RP-HPLC column using an 0.8ml/min as flow rate with methanol: water (80: 20 v/v) mobile phase. Quantification was performed with a UV detector at 214nm, solubility and stability was determined individually in simulated biological fluids at various pH was investigated. The calibration curves of candesartan cilexetil were linear in the range of 10-50 μg/ml (R²=0.999). The developed method was applied to pharmaceutical formulation successfully with no interfering peaks. The percentage recovery was 99.71-100.29%. It was observed that solubility of candesartan cilexetil was increased in all invitro medium, in 1.2 and slightly 7.4 pH and the stability of candesartan cilexetil was stable in pH 1.2 or degraded in pH 7.4 for 24 hours.
LiChrospher® HPLC Columns: LiChrospher® is a reliable and versatile traditionally produced spherical silica carrier with a particle size of 5µm or 10 µm, providing well balanced pressure / separation performance ratio. A broad range of modifications on LiChrospher® are very widely used by HPLC-users all over the world for a broad range of applications. LiChrospher® sorbents are available as reversed phase derivatives (RP-8, RP-18 endcapped, RP-18, RP-18 endcapped and RP-select B), medium polar (NH2, CN, DIOL) and polar derivatives (Si 60). Furthermore LiChrospher® PAH is highly efficient and selective for the separation of PAH; LiChrospher® WP is very well suited for the separation of peptides and low molecular weight proteins. LiChrospher® sorbents are available as Hibar® RT columns or as LiChroCART® cartridges in different lengths ans internal diameters. To operate with LiChroCART® cartridges, the cartridge holder manu-CART® has to be used.
MODEL RELEASED. (High pressure liquid chromatography) Biochemist analyses a new compound synthesized by microcide chemists for its interaction with biological macromolecules using HPLC. - Stock Image C009/4186
denaturing high performance liquid chromatography释义,背景概述,例举denaturing high performance liquid chromatography相关的SCI文献,让我们更理解denaturing high performance liquid chromatography的应用.
This paper reports the utilization of 2-pyrrolecarboxaldehyde-4-phenylsemicarbazone (PPS) as a complexing reagent for the simultaneous determination and separation of Ni(II), Cu(II), Pd(II), and Ag(I) by reversed-phase high-performance liquid chromatography with UV detector. A good separation was achieved using Microsorb C18 column (150 × 4.6 mm i.d.) with a mobile phase consisted of methanol : acetonitrile : water : sodium acetate (1 mM) (68 : 6.5 : 25 : 0.5 v/v/v/v) at a flow rate of 1 mL/min. The detection was performed at 280 nm. The linear calibration range was 2–10 |i|μ|/i|g/mL for all metal ions. The detection limits (S/N = 3) were 80 pg/mL for Ni(II), 0.8 ng/mL for Cu(II), 0.16 ng/mL for Pd(II), and 0.8 ng/mL for Ag(I). The applicability and the accuracy of the developed method were estimated by the analysis of Ni(II) in hydrogenated oil (ghee)
Fish oil made from menhaden (Brevoortia tyrannus) can be used as a dietary supplement for the presence of high levels of the long-chained omega-3 fatty acids, viz. epentaenoic and docosahexanoic. In this work, for the first time, two different multidimensional approaches were developed and compared, in terms of peak capacity, for triacylglycerol characterization. In particular, silver ion chromatography with a silver-ion column and non-aqueous reverse-phase liquid chromatography with a C18 column were tested in both comprehensive (stop-flow) and off-line modes. The use of mass spectra attained by atmospheric pressure chemical ionization for both LC approaches, and the fatty acids methyl esters profile of menhaden oil obtained by gas chromatography analysis, greatly supported the elucidation of the triacylglycerol content in menhaden oil. The off-line approach afforded a better separation and, thus, higher peak capacity to allow identifying and semiquantifying more than 250 triacylglycerols. Such a huge
Definition : High-pressure packed-column liquid chromatography systems in which the packing of the column is made of microparticulate silica gel. The functional groups of the stationary phase may be polar relative to those of the mobile phase (i.e., normal bonded-phase chromatography) or, more usually, nonpolar (i.e., reverse bonded-phase chromatography).. Entry Terms : Reverse-Phase Liquid Chromatography Systems , Normal-Phase Liquid Chromatography Systems , Bonded-Phase Liquid Chromatography Systems. UMDC code : 18278 ...
A unique polypeptide, called enhancing factor (EF), which enhances the binding of labeled epidermal growth factor (EGF) to cells, has been isolated. It has been purified to homogeneity from the acid-soluble proteins of mouse intestines. Earlier, EF was partially purified by two cycles of gel-permeation chromatography on Bio-Gel columns. We now report the final purification of EF on high-performance liquid chromatography (HPLC), using a reverse-phase column (μBondapak C18). The purity of the protein was confirmed when a single peak was obtained in HPLC. Also, a single protein band was obtained in SDS-PAGE. Purified EF has the same properties in vitro as those reported earlier for partially purified EF. ...
A simple and rapid extraction procedure was developed for determining aldehydes in rainwater samples. This extraction technique involved the use of micro-solid-phase extraction in which the sorbent was held within a polypropylene membrane envelope, followed by high-performance liquid chromatographic analysis. Aldehydes such as formaldehyde, acetaldehyde, propionaldehyde and valeraldehyde were used as model compounds. Extraction conditions were optimized. The method linearity ranged between 0.5 and 50μgl-1 with the correlation coefficient of 0.987-0.999. The relative standard deviations (RSDs) of the method ranged from 7 to 12%. Method detection limits were in the range of 0.07-0.15μgl-1, which is lower than those previously reported for solid-phase microextraction combined with gas chromatography-mass spectrometric techniques. The proposed extraction technique was used for determination of aldehydes in rainwater samples to demonstrate the applicability of the method. © 2010 Elsevier B.V ...
A simple and reliable reversed-phase high-performance liquid chromatographic (HPLC) method for the routine determination of vitamins A and E and β-carotene in plasma (or serum) with wavelength-programmed ultraviolet-visible absorbance detection is described. A 200-μl aliquot of serum or plasma sample, after deproteinization with ethanol, and containing tocopherol acetate as internal standard, was extracted with butanol-ethyl acetate. Sodium sulphate was added for dehydration. Analytes of extracted samples were found to be stable for at least four days. A 10-μl aliquot of this organic extract was used for HPLC analysis. The mobile phase was methanol-butanol-water (89.5:5:5.5, v/v) and the flow-rate was set at 1.5 ml/min. The analytes of interest were well separated from other plasma constituents within 22 min at 45°C. The lowest detection limits of vitamins A and E and β-carotene were 0.02, 0.5 and 0.1 μg/ml, respectively. The recovery and reproducibility of the present method were around ...
The next-generation Thermo Scientific Vanquish Duo UHPLC systems are designed to maximize throughput and return on investment (ROI), while providing scientists with a robust and comprehensive understanding of their samples. The systems, which were introduced in February 2018, are on display at Analytica 2018 (Messe München, booth 101, hall B1) in Munich, Germany.. The increasing demand being placed on the pharmaceutical and biopharmaceutical industry to deliver safe and effective medicines that meet regulatory standards is presenting a unique set of analytical challenges, said Fabrizio Moltoni, vice president and general manager, HPLC, chromatography and mass spectrometry, Thermo Fisher Scientific. The Vanquish Duo UHPLC systems provide a high-throughput and robust solution required to enable full characterization of small and large molecules in a manner that creates confidence and quality, while helping to protect customers investment.. Each system in the Vanquish Duo UHPLC family enables ...
The presence of 6-methyladenine and 5-methylcytosine at Dam (GATC) and Dcm (CCA/TGG) sites in DNA of mycobacterial species was investigated using isoschizomer restriction enzymes. In all species examined, Dam and Dcm recognition sequences were not methylated indicating the absence of these methyltransferases. On the other hand, high performance liquid chromatographic analysis of genomic DNA from Mycobacterium smegmatis and Mycobacterium tuberculosis showed significant levels of 6-methyladenine and 5-methylcytosine suggesting the presence of DNA methyltransferases other than Dam and Dcm. Occurrence of methylation was also established by a sensitive genetic assay. ...
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Free Essays from Cram | Raju Chandra et al; A reliable and reproducible reversed-phase high performance liquid chromatography (RP-HPLC) was developed for the...
... (HPLC), formerly referred to as high-pressure liquid chromatography, is a technique in ... liquid chromatography because operational pressures are significantly higher (50-350 bar), while ordinary liquid chromatography ... ligand-exchange chromatography, ion-exchange chromatography of proteins, high-pH anion-exchange chromatography of carbohydrates ... Gas chromatography (GC) at the time was more powerful than liquid chromatography (LC), however, it was believed that gas phase ...
High performance liquid chromatography (HPLC) for column chromatography using high pressure. Fast protein liquid chromatography ... the use of this small packing media causes the high back pressure and is why it is termed high pressure liquid chromatography. ... to move into higher pressure flash chromatography systems and have termed these as medium pressure liquid chromatography (MPLC ... Automated systems will include components normally found on more expensive high performance liquid chromatography (HPLC) ...
"Reversed-phase high-pressure liquid chromatography of some tryptamine derivatives." Journal of Chromatography 157:365-370. ...
"Rapid identification of Clostridium species by high-pressure liquid chromatography" (PDF). Journal of Clinical Microbiology. 22 ... Gas Liquid Chromatography products: (Acetic, Butyric and Lactic Acids). Typically, the symptoms of C. perfringens poisoning are ... This particular disease is rare in the United States; typically, it occurs in populations with a higher risk. Risk factors for ... Genomic research has revealed surprisingly high diversity in C. perfringens pangenome, with only 12.6% core genes, identified ...
Evans MA, Morarity T (January 1980). "Analysis of cocaine and cocaine metabolites by high pressure liquid chromatography". ... The local anesthetic potential of norcocaine has been shown to be higher than that of cocaine, however cocaine continues to be ...
... subpicogram detection of aflatoxins using high-pressure liquid chromatography". Science. 196 (4297): 1439-1441. Bibcode:1977Sci ... and for high performance liquid chromatography (HPLC) Zare is also involved in the development of desorption electrospray ... Snyder, KL; Zare, RN (July 1, 2003). "Cavity ring-down spectroscopy as a detector for liquid chromatography". Analytical ... This opened up the potential for a wide variety of fluid applications, including the detection of single molecules in liquids ...
For the isolation of the compound high pressure liquid chromatography is commonly used (HPLC). In the Fusarium species, ... It's yellow from digested pollen grains, and it rains down from swarms of bees too high to be seen. His theory turns out to be ... It was also found that jungle bees in this area fly collectively in great numbers, at altitudes too high to be easily seen, ... This includes using activated charcoal, which has a high binding capacity of 0.48 mg of T-2 mycotoxin to 1 mg of charcoal. For ...
Instrumental chemistry analyses include separation by high performance liquid chromatography (HPLC), and especially by reversed ... high-pressure liquid extraction or use of ethanol in an immersion extractor. The extraction conditions (temperature, extraction ... Liquid-liquid extraction can be also performed or countercurrent chromatography. Solid phase extraction can also be made on C18 ... Black tea contains high amounts of polyphenol and makes up for 20% of its weight. Concentration can be made by ultrafiltration ...
Muhammad, Naseem; Tsai, Peter S.; Lauback, Ronald G. (1982). "High-Pressure Liquid Chromatography Assay for Dane Salt Potassium ... Journal of Liquid Chromatography. 5 (7): 1349-1355. doi:10.1080/01483918208067593. Lauback, Ronald (1984). "Specific High- ... and Oral Suspensions by Reverse-Phase Ion-Pair Chromatography". Journal of Liquid Chromatography. 7 (6): 1243-1265. doi:10.1080 ... Now since I played trumpet as a youth in high school, it was natural to play dual harmonies with Frank on many of these songs. ...
Assay by high-pressure liquid chromatography". Hepatology. 1 (6): 622-7. doi:10.1002/hep.1840010610. PMID 6796486. Lengyel, G ...
GDGTs such as crenarchaeol can be analyzed using high-performance liquid chromatography/atmospheric pressure chemical ... "Analytical methodology for TEX86 paleothermometry by high-performance liquid chromatography/atmospheric pressure chemical ... Most GDGTs degrade at between 240 and 300 °C and so are not found in rocks that have undergone heating to temperatures higher ... Originally, it was believed that GDGT membrane lipids were an adaption to life at high temperatures and acidities. Because the ...
Anion-exchange chromatography Chromatofocusing High performance liquid chromatography Isoelectric point Ninfa, Alexander J., ... Incorporation of high temperature and pressure allows a significant increase in the efficiency of ion chromatography, along ... "The art and science of forming packed analytical high-performance liquid chromatography columns". Journal of Chromatography A. ... Svec, Frantisek.; Frechet, Jean M. J. (1992). "Continuous rods of macroporous polymer as high-performance liquid chromatography ...
"Simultaneous Determination of Four Alkaloids in Lindera aggregata by Ultra-High-Pressure Liquid Chromatography-Tandem Mass ... Spectrometry". Journal of Chromatography A. 1212 (1-2): 76-81. doi:10.1016/j.chroma.2008.10.017. PMID 18951552. v t e (Articles ...
"Simultaneous determination of four alkaloids in Lindera aggregata by ultra-high-pressure liquid chromatography-tandem mass ... spectrometry". Journal of Chromatography A. 1212 (1-2): 76-81. doi:10.1016/j.chroma.2008.10.017. PMID 18951552. v t e (Articles ...
"Analysis of derivatized and underivatized theanine enantiomers by high-performance liquid chromatography/atmospheric pressure ... Finger, Andreas; Kuhr, Susanne; Engelhardt, Ulrich (1992). "Chromatography of tea constituents". Journal of Chromatography. 624 ... Natural Standard rates the evidence to support the usage of theanine for anxiety reduction, blood pressure control, and mood ... which has high theanine content. Theanine is substantially present in black, green, and white teas from Camellia sinensis in ...
Detection of ketamine and its metabolites in urine by ultra high pressure liquid chromatography-tandem mass spectrometry. J. ... Low blood pressure is dangerous for people with severe head injury and ketamine is unlikely to lower blood pressure - ... Liver toxicity of ketamine involves higher doses and repeated administration. In a group of chronic high dose ketamine users, ... but is presumed to be high. Among the less invasive routes, the intranasal route has the highest bioavailability (45-50%) and ...
"Simultaneous determination of four alkaloids in Lindera aggregata by ultra-high-pressure liquid chromatography-tandem mass ... spectrometry". Journal of Chromatography A. 1212 (1-2): 76-81. doi:10.1016/j.chroma.2008.10.017. PMID 18951552. Dholvitayakhun ...
... and high pressure liquid chromatography". Biochemistry. 17 (11): 2124-2133. doi:10.1021/bi00604a016. ISSN 0006-2960. PMID ...
High-performance liquid chromatography separates analytes by passing them, under high pressure, through a column filled with ... Chromatography Electrophoresis High-performance liquid chromatography Capillary electrophoresis Electrochromatography Dittmann ... Capillary electrochromatography is a combination of two analytical techniques, high-performance liquid chromatography and ... Firstly, the pressure driven flow rate across a column depends directly on the square of the particle diameter and inversely on ...
Eluate from a high-pressure liquid chromatograph (HPLC) can be also introduced to the reaction zone of the DART source and ... Gas chromatography has been carried out by coupling gas chromatography columns directly into the DART gas stream through a ... Liquids are typically analyzed by dipping an object (such as a glass rod) into the liquid sample and then presenting it to the ... glow discharge Atmospheric pressure chemical ionization Atmospheric pressure photoionization Desorption atmospheric pressure ...
... and ultra-high pressure liquid chromatography. He has been an Lilly Analytical Research Fellow, Alfred P. Sloan Fellow, NSF ... Robert (Bob) Kennedy (born 1962) is an American chemist specializing in bioanalytical chemistry including liquid chromatography ... "ACS Award in Chromatography: Robert T. Kennedy , Chemical & Engineering News". Chemical Engineering & News. "CASSS ... 12:1. Chromatography Today. March 2019. Retrieved 17 December 2019. Rome, Karen (4 February 2019). "ChromSoc Martin Medal 2019 ...
The liquid solvent (mobile phase) is delivered under high pressure (up to 400 bar or 300.000 torr) into a packed column ... The high pressure is necessary to achieve a constant flow rate for reproducible chromatography experiments. Depending on the ... The column is the most important component of the LC system and is designed to withstand the high pressure of the liquid. ... Liquid chromatography is a method of physical separation in which the components of a liquid mixture are distributed between ...
... ion-exchange chromatography, and high pressure liquid chromatography. Phenypressin differs from the common hormone, arginine ... Secondly, it can also cause vasoconstriction, increasing the blood pressure. This neurohypophysial hormone was identified and ...
It was fortunate indeed that, just around that time, the technique of high pressure liquid chromatography (HPLC) had been ... Huber, J. F. K. (1969). "High Efficiency, High Speed Liquid Chromatography in Columns". Journal of Chromatographic Science. 7 ( ... Using cadmium(II) as the coordinating metal ion led to a very high diastereoselectivity: 44-46 in favor of the natural A/D- ...
Both drugs can be assayed by high pressure liquid chromatography and by radioimmunoassay and plasma ACE inhibition remains ... inhibitor and is used to treat high blood pressure, heart failure, and after heart attacks. For high blood pressure it is ... Serious side effects may include low blood pressure, liver problems, high blood potassium, and angioedema. Use is not ... Lisinopril is typically used for the treatment of high blood pressure, congestive heart failure, and diabetic nephropathy and ...
The work of Martin and Synge also set the stage for high performance liquid chromatography, suggesting that small sorbent ... particles and pressure could produce fast liquid chromatography techniques. This became widely practical by the late 1960s (and ... Martin, A J P; Synge, R L M (1941). "Separation of the higher monoamino-acids by counter-current liquid-liquid extraction: the ... Touchstone, Joseph C. (1993). "History of Chromatography". Journal of Liquid Chromatography. 16 (8): 1647-1665. doi:10.1080/ ...
Liquid chromatography-mass spectrometry (LC-MS), and high performance (also called high pressure) liquid chromatography (HPLC ... Too high a false positive rate, without an operator that understands the context, can cause real alarms to be ignored. In an ... This vehicle can keep up with moving troops, detecting liquid and vapor hazards. Newer versions, like the M1135 Nuclear, ... Materials MASINT involves the collection, processing, and analysis of gas, liquid, or solid samples, is critical in defense ...
"Trace analysis of peroxide explosives by high performance liquid chromatography-atmospheric pressure chemical ionization-tandem ... high performance liquid chromatography/mass spectrometry (HPLC/MS), and HPLC with post-column derivitization. Acetone peroxide ... DADP has lower molecular weight and higher vapor pressure. This means that DADP is more prone to sublimation than TATP. Several ... "Analysis of triacetone triperoxide by gas chromatography/mass spectrometry and gas chromatography/tandem mass spectrometry by ...
... by the mid-1970s thanks to high-pressure liquid chromatography (HPLC) methods. Minor allergic reactions still occur ... The basic appeal of hypoglycemic agents by mouth is that most people would prefer a pill or an oral liquid to an injection. ... It is also used along with glucose to treat high blood potassium levels. Use during pregnancy is relatively safe for the baby. ... It is simply a nuisance for people to inject whenever they eat carbohydrate or have a high blood glucose reading. It is ...
It did not lower systolic blood pressure or improve weight at birth. Both liquid chromatography and liquid chromatography/mass ... including women with high blood pressure as part of pre-eclampsia. ... reduces blood pressure with pooled estimates of 5.4 mmHg for systolic blood pressure and 2.7 mmHg for diastolic blood pressure ... Forbes SC, Bell GJ (June 2011). "The acute effects of a low and high dose of oral L-arginine supplementation in young active ...
Solvent assisted inlet ionization can be coupled not only to liquid chromatography (LC) but also to nano LC. Ionization at ... The sensitivity of LSII, for protein detection, is higher by an order of magnitude compared to ESI. Solvent assisted inlet ... The solvent flows through the capillary column without the use of a pump due to the pressure difference between ambient ... A New Highly Sensitive Approach for Liquid Chromatography/Mass Spectrometry of Small and Large Molecules". Analytical Chemistry ...
"Ion Spray Interface For Combined Liquid Chromatography/Atmospheric Pressure Ionization Mass Spectrometry". Analytical Chemistry ... In 1983 LC-MS-MS using ion evaporation, a spray method similar to electrospray but compatible with higher flow rates of up to 1 ... In 2010 SCIEX acquired the liquid chromatography business of Eksigent Corporation and now offers a range of liquid ... "Liquid Chromatography Mass Spectrometry Market Size By 2027". Retrieved 2022-05-28. Gelpí, ...
Many coffee companies use high-performance liquid chromatography (HPLC) to measure how much caffeine remains in the coffee ... Green coffee beans are steamed and then added to a high pressure vessel. A mixture of water and CO2 is circulated through the ... After several hours of high temperatures, the triglycerides in the oils remove the caffeine, but not the flavor elements, from ... The CO2 is then recirculated to the pressure vessel. To ensure product quality, manufacturers are required to test the newly ...
At high pressure 1/n = 0, hence extent of adsorption becomes independent of pressure. The Freundlich equation is unique; ... Articles with short description, Short description matches Wikidata, Chromatography). ... for the concentration of a solute adsorbed onto the surface of a solid and the concentration of the solute in the liquid phase ... the rate of adsorption saturates even after applying higher pressure. Thus, the Freundlich adsorption isotherm fails at higher ...
This involves using high heat and pressure to break down the chemical bonds between each styrene compound. Pyrolysis usually ... Simon, E. (1839) "Ueber den flüssigen Storax (Styrax liquidus)" [On liquid storax (Styrax liquidus)], Annalen der Chemie, 31 : ... Journal of Chromatography A. 315: 201-210. doi:10.1016/S0021-9673(01)90737-X. Quoted from a campaign site giving no details of ... the chains can take on a higher degree of confirmation and slide past each other. This intermolecular weakness (versus the high ...
The concentration of chemical species in vapor or liquid phases as well as in more complex mixtures can be determined with high ... Different mechanical signals such as pressure, strain, torsion and bending can be detected with photonic crystal sensors. ... "On-chip Fabry-Pérot interferometric sensors for micro-gas chromatography detection". Sensors and Actuators B: Chemical. 159 (1 ... Due to their high sensitivity, inherent flexibility, and small diameters, they can be used in a variety of situations requiring ...
Solvents used in high-performance liquid chromatography (HPLC) are often sparged with helium. In biochemical engineering, ... According to Henry's law, the concentration of each gas in a liquid is proportional to the partial pressure of that gas (in the ... Froth flotation, the use of gas bubbles to separate or extract hydrophobic liquids and/or solids from hydrophilic liquids M. W ... and/or dissolved volatile liquid(s) from that liquid. It is a method of degassing. ...
Compounds can then be further differentiated using reversed-phase high-performance liquid chromatography-mass spectrometry. ... microbial and physicochemical processes as well as increased temperature and pressure, which lead to transformations of ... Additionally, in different regions of the strait the biogenic substances with the highest annual transfer were constant. These ... In this study the biogenic substance concentrations, transformation frequency, and turnover were all highest in the upper layer ...
This resulted in higher frequency of lactase persistence. Lactase persistence became high in regions such as Europe, ... Chromatography can be used to separate and identify undigested sugars present in faeces. Although lactose may be detected in ... Some barbecue sauces and liquid cheeses used in fast-food restaurants may also contain lactose. Lactose is often used as the ... The unabsorbed sugars and fermentation products also raise the osmotic pressure of the colon, causing an increased flow of ...
Techniques available to measure blood concentrations include thin layer chromatography, gas liquid chromatography with or ... However, combinations of high doses of benzodiazepines with alcohol, barbiturates, opioids or tricyclic antidepressants[ ... although catecholamines such as norepinephrine or dopamine may be required to increase blood pressure. Bradycardia is treated ... A 1993 British study found flurazepam and temazepam to have the highest number of deaths per million prescriptions among ...
The liquid phase ligand binding assay of Immunoprecipitation (IP) is a method that is used to purify or enrich a specific ... The radiolabeled ligands are spatially located by a PET scanner to reveal areas in the organism with high concentrations of ... Smith SM (2011). "Strategies for the purification of membrane proteins". Protein Chromatography. Methods in Molecular Biology. ... in addition to maintaining atmospheric pressure and temperature rates in order to reduce humidity. On-Bead Ligand Binding ...
... in surface and pore water by high-resolution sampling-direct injection-ultra high performance liquid chromatography-tandem mass ... In 1950, metformin, unlike some other similar compounds, was found not to decrease blood pressure and heart rate in animals. ... "Determination of metformin in human plasma using hydrophilic interaction liquid chromatography-tandem mass spectrometry". ... Also available is liquid metformin (sold only as Riomet in the US), where 5 mL of solution contains the same amount of drug as ...
Journal of Liquid Chromatography & Related Technologies. Informa UK Limited. 20 (16-17): 2907-2929. doi:10.1080/ ... Molecules with higher kinetic energy in the region of higher gas temperature impinge on the particle with greater momenta than ... For pressures p {\displaystyle p} , where the free mean path of the gas is much larger than the characteristic size r 0 {\ ... This is referred to as a radiation pressure force. This force depends on light intensity and particle size but has nothing to ...
Desorption atmospheric pressure photoionization (DAPPI) is a solid-liquid extraction ambient ionization method that enables the ... Van Berkel, Gary J.; Kertesz, Vilmos; King, Richard C. (2009). "High-Throughput Mode Liquid Microjunction Surface Sampling ... A New Highly Sensitive Approach for Liquid Chromatography/Mass Spectrometry of Small and Large Molecules". Analytical Chemistry ... "Liquid sampling-atmospheric pressure glow discharge (LS-APGD) ionization source for elemental mass spectrometry: preliminary ...
... including but not limited to thin-layer chromatography (TLC) and high-pressure liquid chromatography. Voltammetry ... J. Planar Chromatography. 1996, 9:269. Hoekstra JC, Johnson DC. Anal. Chim. Acta. 1999, 390:45. (All articles with vague or ... high sensitivity screening can be obtained utilizing SWV. For this reason, squarewave voltammetry has been utilized in numerous ...
At atmospheric pressure, it has the highest critical temperature of the elemental superconductors at 9.2 K. Niobium has the ... Newer processes use the liquid extraction of the fluorides from aqueous solution by organic solvents like cyclohexanone. The ... This report included an initial chemical examination: the thermal gradient version of the gas-chromatography method was applied ... Instead, vanadium is produced by heating vanadium oxide with calcium in a pressure vessel. Very high-purity vanadium is ...
MDPV may be quantified in blood, plasma or urine by gas chromatography-mass spectrometry or liquid chromatography-mass ... High doses have been observed to cause intense, prolonged panic attacks in stimulant-intolerant users, and there are anecdotal ... in these patients can cause an unopposed peripheral alpha-adrenergic effect with a dangerous paradoxical rise in blood pressure ... by gas chromatography/mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry". Rapid ...
Fiet J, Le Bouc Y, Guéchot J, Hélin N, Maubert MA, Farabos D, Lamazière A (March 2017). "A Liquid Chromatography/Tandem Mass ... leading to falsely high cortisol levels when the true cortisol is actually low. The selectivity offered by liquid ... 2004). "Analysis of 21-deoxycortisol, a marker of congenital adrenal hyperplasia, in blood by atmospheric pressure chemical ... Hawley JM, Keevil BG (September 2016). "Endogenous glucocorticoid analysis by liquid chromatography-tandem mass spectrometry in ...
Since PEG is a flexible, water-soluble polymer, it can be used to create very high osmotic pressures (on the order of tens of ... Polyethylene glycol is also commonly used as a polar stationary phase for gas chromatography, as well as a heat transfer fluid ... They vary in consistency from liquid to solid, depending on the molecular weight, as indicated by a number following the name. ... Very high-purity PEG has recently been shown to be crystalline, allowing determination of a crystal structure by x-ray ...
Electrical Resistivity of Liquid Carbon at High Pressure', in MH Manghnani, W Nellis & MF.Nicol (eds), Science and Technology ... Ion Chromatography, John Wiley & Sons, New York, ISBN 3-527-61325-0 Gary S 2013, 'Poisoned Alloy' the Metal of the Future', ... 863-68, doi:10.1038/nature07736 Oganov AR 2010, 'Boron Under Pressure: Phase Diagram and Novel High Pressure Phase,' in N ... 21-53, ISBN 3-527-30265-4 Millot F, Rifflet JC, Sarou-Kanian V & Wille G 2002, 'High-Temperature Properties of Liquid Boron ...
"Nontargeted SWATH acquisition for identifying 47 synthetic cannabinoid metabolites in human urine by liquid chromatography-high ... and elevated blood pressure." Several states independently passed acts making it illegal under state law, including Kansas in ... for 46 synthetic cannabinoids in serum employing liquid chromatography-quadrupole ion trap mass spectrometry with high- ... Counterfeit cannabis-liquid (c-liquid) for e-cigarettes: Synthetic cannabinoids are increasingly offered in e-cigarette form as ...
These lamps produce light through a high-intensity discharge (HID) by passing an electric arc through vapourized high-pressure ... Liquid Injection and Headspace Solid-Phase Microextraction for Crude Oil Analysis by Gas Chromatography with Mass Spectrometer ... high-pressure xenon gas. These lamps offer high intensities and an unfiltered spectrum which matches reasonably well to ... High-pressure argon gas cycles between an anode and a cathode, with a water vortex flowing along the inside quartz tube wall to ...
Fiet, J.; Le Bouc, Y.; Guéchot, J.; Hélin, N.; Maubert, M. A.; Farabos, D.; Lamazière, A. (2017). "A Liquid Chromatography/ ... As 21-deoxycortisol can be at high levels in congenital adrenal hyperplasia, and it has structural similarity to cortisol, it ... in blood by atmospheric pressure chemical ionization and electrospray ionization using multiple reaction monitoring". Rapid ... Hawley JM, Keevil BG (September 2016). "Endogenous glucocorticoid analysis by liquid chromatography-tandem mass spectrometry in ...
Comparative studies using reliable and exact methods such as liquid chromatography-mass spectrometry (LC-MS) and IA in ... Due to the high concentrations achieved, progesterone by intramuscular injection at the usual clinical dose range is able to ... No side effects have been reported as far as lipid profile, coagulation factors and blood pressure are concerned. Progesterone ... 5α-Reductase is a major enzyme involved in the metabolism of progesterone and is known to be expressed in skin in high amounts ...
Due to FFF's similarity to Liquid Chromatography, in ways of a liquid mobile phase passing through the channel, the most common ... High Temperature Asymmetric Flow Field-Flow Fractionation is available for the separation of high and ultra-high molar mass ... The decrease of air pressure going up from sea level has the same exponential decrease which is described in the Barometric ... It is similar to liquid chromatography as it works on dilute solutions or suspensions of the solute. Separation is achieved by ...
Emil Fischer Hermann Staudinger heterocyclic compound Hexane Hiddenite Hideki Shirakawa High performance liquid chromatography ... Urea Uric acid UV/VIS spectroscopy Valence Van der Waals radius Van der Waals force Vanadium Vapor pressure Vapour pressure ... of sound Sperrylite Spinel Spodumene stable isotope standard temperature and pressure Standard Ambient Temperature and Pressure ... Anfinsen Chromatography Chromite Chromium Chrysoberyl Chrysolite cinnabar Cinnabarite Citric acid Citrine quartz Clay Cleveite ...
Porous silica Stöber materials have applications in catalysis and liquid chromatography due to their high surface area and ... Aerogel is made by high temperature and pressure-critical-point drying of a gel composed of colloidal silica structural units ... Aerogels are highly porous ultralight materials in which the liquid component of a gel has been replaced with a gas, and are ... The newly acquired understanding has enabled researchers to exert a high degree of control over particle size and distribution ...
... or more reliably by gas chromatography combined with mass spectrometry (GC/MS). Liquid chromatography (LC) techniques are also ... Strains used in medicine are often bred for high CBD content, and strains used for recreational purposes are usually bred for ... Pate, DW (1999). Anandamide structure-activity relationships and mechanisms of action on intraocular pressure in the ... "Analysis of alkamides in roots and achenes of Echinacea purpurea by liquid chromatography-electrospray mass spectrometry". ...
This process removes the high molecular weight compounds through ultrafiltration, absorption chromatography or oil filtration. ... For this reason, passing gas through the liquid provides a favorable condition for the compounds to leave the liquid. The ... 547 Concentration of tea is normally done through reduction of pressure. At high temperatures, the theaflavins in the solution ... By forcing the liquid extract through a nozzle, the solution atomizes, or becomes very fine droplets. These droplets are met ...
Liquid chromatography-mass spectrometry LC-MS can then be performed for peptide mass fingerprinting; however, liquid ... The higher temperatures of the Precambrian affected optimum growth temperatures. Higher thermostability in proteinaceous ... This pressured various groups of anaerobic prokaryotes, changing the microbial diversity and global metabolome, as well as ... With the advent of soft-ionization and use of coupled liquid chromatography (LC) and tandem MS systems (i.e. MALDI-TOF-MS and ...
High-pressure liquid chromatography of steroids secreted by human adrenal and testis cells in monolayer culture. In: Journal of ... High-pressure liquid chromatography of steroids secreted by human adrenal and testis cells in monolayer culture. / OHare, M. J ... N2 - Reversed-phase high-pressure liquid chromatography with gradient elution on Zorbax-ODS columns has been used to separate, ... AB - Reversed-phase high-pressure liquid chromatography with gradient elution on Zorbax-ODS columns has been used to separate, ...
... a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to ... a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to ... a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to ... a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to ...
Purchase Chromatography Today - 5th Edition. Print Book & E-Book. ISBN 9780444884923, 9780444596192 ... 5. Instrumental Aspects of High Pressure. Liquid Chromatography Introduction. Requirements with Respect. to Extracolumn ... Retention in Gas-Liquid. Chromatography. Gas-Solid Chromatography. Preparative-Scale Gas. Chromatography. References. 3. ... Retention Mechanisms in Liquid Chromatography. Method. Development Strategies for Liquid Chromatography. Preparative-. Scale ...
Chromatography, High Pressure Liquid Healthy Volunteers Humans Indicator Dilution Techniques Isotopes Molecular Structure ... A Simplified Method for Quantifying Sulfur Mustard Adducts to Blood Proteins by Ultra-High Pressure Liquid Chromatography- ... A Simplified Method for Quantifying Sulfur Mustard Adducts to Blood Proteins by Ultra-High Pressure Liquid Chromatography- ... The adducted tripeptide is purified by solid phase extraction, separated by ultra high pressure liquid chromatography, and ...
High-Pressure Liquid Chromatography (HPLC). HPLC separates mixtures of compounds in solution. This method is widely used in ... Gas Chromatography/Mass Spectrometry (GC/MS). GC/MS separates mixtures of volatile compounds, and identifies the individual ... AA detects individual chemical elements by measuring the absorption of light by a high-temperature vapor. This method is widely ...
... ion exchange high-performance (pressure) liquid chromatography; RBC: red blood cell. Source: Reference 39 (based on data from ... HbA: hemoglobin A; HbC: hemoglobin C; HbF: fetal hemoglobin; HbS: sickle hemoglobin; HPLC: high-performance (pressure) liquid ... High altitude, erythropoietin use. Increased production of RBCs. Acute and chronic blood loss. Increased fraction of young RBCs ... Different rates of glycation of hemoglobin ("low" or "high" glycators). Chronic aspirin use. Increased A1C: due to interference ...
Antihypertensive drugs are a class of drugs that are used for treating hypertension (high blood pressure) and cardiovascular ... and high performance liquid chromatography (HPLC) system (Agilent Technologies, model LC-1200, Englewood, USA) equipped by an ... "Simultaneous quantification of enalapril and enalaprilat in human plasma by high-performance liquid chromatography-tandem mass ... "Determination of enalapril in human plasma by high performance liquid chromatography-electrospray ionization mass spectrometry ...
Chromatography is a way of separating two or more chemical compounds. Chemical compounds are chemicals that are bonded together ... These include gas, high pressure liquid, or ion exchange chromatography.. In general, chromatography uses the differences in ... Chromatography is a way of separating two or more chemical compounds. Chemical compounds are chemicals that are bonded together ... A.D.A.M. is also a founding member of Hi-Ethics. This site complies with the HONcode standard for trustworthy health ...
Excised buttons were frozen and Ciloxan concentration determined by high-pressure liquid chromatography. Ciloxan corneal tissue ...
With the advent of ultra-high pressure liquid chromatography (UHPLC) and multidimensional chromatography applications, peak ... Separation and Identification Techniques for Membrane Proteins Using Ultra-high Pressure Liquid Chromatography Coupled to Mass ... Separation and Identification Techniques for Membrane Proteins Using Ultra-High Pressure Liquid Chromatography Coupled to Mass ... Separation and Identification Techniques for Membrane Proteins using Ultra-High Pressure Liquid Chromatography coupled to Mass ...
Liquid chromatography; Chromatographic analysis; Author Keywords: neuron-specific enolase; high-pressure liquid chromatography ... and identification of enolase isozymes of brain and sciatic nerve by high-pressure liquid anion-exchange chromatography. ...
Almost half of the U.S. adult population has high blood pressure - or hypertension - and about 20% of these patients have ... system which was further followed by a multiplexed and targeted proteomic liquid chromatography-tandem mass spectrometry ... Using oral blood pressure drug to treat Type 1 diabetes shows benefits for at least two years Use of the drug verapamil to ... A new study used glycoprotein profiling technology platform that couples high-resolution LC-MS for glycoprotein analysis in ...
Affinity Chromatography. Ion Exchange Chromatography. Gel-filtration Chromatography. High Pressure Liquid Chromatography. ... Liquid-handling Systems & Robots. Crystallization Plates. Others. Reagents and consumables. Crystallization Screens. Others. ... In addition, high cost and time consuming method further restrains the growth of protein crystallization and crystallography ... In addition, increasing need for high resolution information on protein structures will further drive the growth of ...
Chromatography, High Pressure Liquid * DNA Mutational Analysis * DNA Primers/genetics * Genetic Predisposition to Disease ...
Chromatography, High Pressure Liquid. Taylor AW, Bruno RS, Frei B, Traber MG. 2006. Benefits of prolonged gradient separation ... for high-performance liquid chromatography-tandem mass spectrometry quantitation of plasma total 15-series F-isoprostanes.. ...
Higher doses may be needed to maintain plasma voriconazole concentrations during long-term treatment. Safety and efficacy of ... Higher doses resulted in disproportional increases in the maximum plasma voriconazole concentration and area under the curve. ... and 18 mg of voriconazole/kg orally and plasma concentrations of voriconazole were determined via high-pressure liquid ... chromatography. In a multiple-dose trial, voriconazole (18 mg/kg) was administered orally to 6 birds every 12 hours for 9 days ...
... at a high pressure.. Low Pressure Liquid Chromatography. Low pressure liquid chromatography (LPLC) is a chromatographic ... High performance liquid chromatography (HPLC) can be used to separate and identify different large biomolecules such as protein ... Supported Liquid Extraction Columns, Resins & Accessories. Our EXtrelut® NT simplifies the liquid-liquid extraction (LLE) by ... Webinar: Advances in Liquid Chromatography Separations Employing Carbon Particles. This presentation focuses on recent advances ...
Fast Protein Liquid Chromatography System (FPLC) (Amersham Biosciences) *High Pressure Liquid Chromatography System (HPLC) ( ... liquid scintillation counter, lyophilizer and freeze-dryer, cell porator, high-speed and ultra-high-speed centrifuges and ultra ... Cryopreservation tanks with monitored liquid nitrogen supply (2 Thermolyne Locator Jr. Cryo Biological System Storage, Cryosafe ... Beckman High-speed tabletop ultra-centrifuge, and Amersham Biosciences AKTA FPLC System. Based upon CAU Title III funds, one of ...
Yasumoto, T.; Takizawa, A. Fluorometric measurement of yessotoxins in shellfish by high-pressure liquid chromatography. Biosci ... high toxicity of YTX, in the nanomolar range, was observed on 27 of 58 cellular lines checked after 48 h incubation. High YTX ... Feature Papers represent the most advanced research with significant potential for high impact in the field. Feature Papers are ... high toxic effects were reported in fresh cortical mice neurons and in long cultured rat cerebellar neurons [39,56]. The effect ...
High performance liquid chromatography-mass spectrometry (HPLC-MS), specifically atmospheric-pressure ionization ... View MoreLiquid Chromatography (LC/HPLC)Gas Chromatography (GC)Sample PreparationMass SpectrometryPharmaceutical Analysis ... Liquid Chromatography (LC/HPLC)Gas Chromatography (GC)Sample PreparationMass SpectrometryPharmaceutical AnalysisEnvironmental ... Mobile phones having high-quality camera features to take market share from the digital camera companies ...
The atrazine in the water extract was assayed with high-pressure liquid chromatography (HPLC). The half-life of atrazine in ... By the end of the growing season, 0-d concentrations between 120 and 240 ppt resulted in higher percentages of tubers with ... Common cocklebur emergence was higher when the mean soil temperature was , 15 C, and the daily thermal fluctuation was , 7.5 C ... The starch content of seeds from introduced populations was higher than that of seeds from native populations. Regression ...
The test principle utilizes high performance liquid chromatography-atmospheric pressure photoionization-tandem mass ... was utilized and in 2005-2006 high performance liquid chromatography-atmospheric pressure photoionization-tandem mass ... In 2003-2004 high performance liquid chromatography electrospry ionization mass spectrometric (LC-ESI-MS/MS) detection (Rybak, ... Crossover studies comparing samples analyzed by LC-ESI-MS/MS and LC-APPI-MS/MS demonstrated high correlation coefficients (r, ...
High Pressure Liquid Chromatography 8% * Pancreatic Ribonuclease 8% * Malate Dehydrogenase 8% * beta-Lactamase Inhibitors 8% ...
Ultra-high pressure liquid chromatography apparatus to study the pharmacokinetics of small molecules. 1601. 1. $142,006.00. ... Liquid Xenon detector for 10ps time of flight positron emission tomography. 1510. 5. $33,000.00. ...
The frequency of thalassaemia and/or G6PD deficiency with SCD was high and this may have an effect on the severity of the ... of the total Hb by high-pressure liquid chromatography. Thalassaemia was indicated by microcytic hypochromic red cells: mean ... High level of fetal Hb (HbF) was , 20%. A high nucleated red blood cell (RBC) count was ≥ 1 and high white blood cell (WBC) ... using high-performance liquid chromatography (HPLC) (Bio-Rad); G6PD activity, using a quantitative assay kit (Randox ...
For all samples, a fully validated high-pressure liquid chromatography procedure with fluorescence detection was used. The ... Considering the substantial differences in concentrations in blood samples taken from various sites in the body and the high ... found substances were also identified with liquid chromatography-tandem mass spectrometry. Our data confirm that blood sampling ...
  • The test principle utilizes high performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry (HPLC-APPI-MS/MS) for the quantitative detection of genistein, daidzein, equol, O-desmethylangolensin, enterodiol, and enterolactone. (
  • N. caninum tachyzoite lysate was prepared from cultured N. caninum tachyzoites and separated into 6 fractions by DEAE anion exchange chromatography using High Pressure Liquid Chromatography (HPLC). (
  • CD4+ T cell proliferation assay results indicated that antigenic activity was associated with proteins from HPLC fractions 4 through 6 with fraction 5 exhibiting the highest antigenic activity. (
  • The AZURA® Educational system allows an easy and fast implementation of liquid chromatography (HPLC, high pressure liquid chromatography) and promotes a deeper understanding of this separation method. (
  • A more up-to-date method uses high pressure liquid chromatography (HPLC). (
  • Preparations of HRA have now been analyzed by high-performance liquid chromatography (HPLC). (
  • 1.2.2 High performance liquid chromatography (HPLC): HPLC is abbreviated as High Performance Liquid Chromatography or High Pressure Liquid Chromatography. (
  • All of these derivatives can be separated in a single run either by thin-layer or high-performance liquid chromatography (TLC or HPLC). (
  • Waters millennium 2010 chromatography manager with a 515 HPLC pump and Waters 24879 dual absorbance UV detector was used. (
  • The final solution was analyzed by high pressure liquid chromatography (HPLC) with a fluorescence detector using an excitation wavelength of 270 nanometers and an emission wavelength of 415 nanometers. (
  • If you need to combine the high flowrates, little matrix sensitivity, low back pressure, and long lifetime of Chromolith® HPLC columns with even higher efficiency, you need Chromolith® HighResolution. (
  • Chromolith® HighResolution RP-18 endcapped HPLC columns are perfect for fast, robust and highly efficient separation of hydrophobic to medium polar compounds at low column back pressure. (
  • Like all our Chromolith® HPLC columns, Chromolith® HighResolution RP-18e columns consist of a monolithic rod of high-purity silica with a bimodal structure: macropores reducing back pressure, and mesopores creating a very large active surface area. (
  • Mini-UniPrep G2 Syringeless Filters provide a fast and easy way to remove Particulates from samples being prepared for Ultra High Performance Liquid Chromatography (UHPLC)/High Performance Liquid Chromatography (HPLC) analysis. (
  • The analysis was made by high performance liquid chromatography (HPLC). (
  • In this work, a rapid and sensitive ultra-high-pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to determine AA I and AA II in herbal products and biological fluids. (
  • For such complex mixtures, high resolution liquid chromatography (LC) is commonly utilized along with mass spectrometry (MS) for comprehensive proteomic analysis. (
  • Benefits of prolonged gradient separation for high-performance liquid chromatography-tandem mass spectrometry quantitation of plasma total 15-series F-isoprostanes. (
  • 2008) was utilized and in 2005-2006 high performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometry (LC-ESI-MS/MS) was utilized. (
  • The found substances were also identified with liquid chromatography-tandem mass spectrometry. (
  • Diagnosis was established by high plasma tyrosine and normal plasma phenylalanine levels using plasma high-pressure liquid chromatography and tandem mass spectrometry. (
  • A targeted liquid chromatography-multiple-reaction monitoring mass spectrometry method was developed and used to quantify ß-ODAP in the analysed extracts. (
  • Ultra-performance liquid chromatography coupled with tandem mass spectrometry was performed to quantify 38 serum BAs. (
  • The main components and functional groups of bio-oil with an acid catalyst were characterized by gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). (
  • Avantor has the resources to make your Chromatography or Mass Spectrometry applications run efficiently and effectively-from the measuring apparatus needed for chromatography, or the proteins used to fulfill sample manipulation during mass spectrometry. (
  • These include gas, high pressure liquid, or ion exchange chromatography. (
  • The separation and identification of enolase isozymes of brain and sciatic nerve by high-pressure liquid anion-exchange chromatography. (
  • The production of large quantities of the lymphokine(s) histamine-releasing activity (HRA) and its partial purification by Sephadex G-75 and ion-exchange chromatography on carboxymethyl (CM) Sepharose 6B have been detailed (M. A. Lett-Brown, D. O. Thueson, D. E. Plank, M. P. Langford, and J. A. Grant, Cell. (
  • The heart of the SepTor ion exchange contactor comprises a unique liquid flow distribution concept (the multi-port distributor valve) which physically allows the use of truly counter-current ion exchange, chromatography or other adsorptions for the recovery / purification of pharma intermediates. (
  • The hardest part of any gel permeation chromatography/size-exclusion chromatography (GPC/SEC) separation is selecting the right columns and developing a robust method. (
  • We report on a new integrated platform for automated harvesting of whole unclarified cell-culture broths, followed by in-line tandem affinity-capture, pH neutralization and size-exclusion chromatography of recombinant antibodies expressed transiently in mammalian human embryonic kidney 293T-cells at the 1-L scale. (
  • The results showed that the overall performances of the preparative automated system were higher compared to the conventional downstream process including manual harvesting and purification. (
  • Laboratory pilot SepTor unit for chromatography / ion exchange on a small / preparative scale (photo courtesy Xendo Manufacturing). (
  • Chromatography Today provides a comprehensive coverage of various separation methods: gas, liquid, thin-layer, and supercritical fluid-chromatography, and capillary electrophoresis. (
  • Is high pressure liquid chromatography an effective screening tool for characterization of molecular defects in hemoglobinopathies? (
  • Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed. (
  • This book should be suitable for use as a graduate-level student textbook in separation science, a text for professional institutes offering short courses in chromatography, and as a self-study guide for chromatographers to refresh their knowledge of the latest developments in the field. (
  • The modified silica gels were evaluated for the usefulness as high-performance liquid chromatography stationary phases for the separation of π-electron-rich polyaromatic hydrocarbons (PAHs) such as naphthalene and phenanthrene. (
  • However, it is very difficult to alter the molar mass separation range when higher or lower molar masses need to be separated. (
  • For fast separation of simple mixtures: 50 mm Chromolith® HighResolution offer short run times and lowest back pressures and are ideal for gradient analyses. (
  • A high performance liquid chromatography photo diode array method was developed for simultaneous quantiï¬ cation of ï¬ ve marker compounds and for establishing the chemical fingerprint of Andrographis paniculata from 28 different locations of Eastern India. (
  • The high performance liquid chromatography fingerprint combined with chemometric approaches could be used as an effective tool for discriminating the herb from different origins and quality control of Andrographis paniculata . (
  • For all samples, a fully validated high-pressure liquid chromatography procedure with fluorescence detection was used. (
  • Principles of Quantitation in Column Chromatography. (
  • Overall, the IMER produced high protein coverage (for both model and complex sample analysis) in a ~10 sec volumetric residence time on column (Chapter 4). (
  • A new study used glycoprotein profiling technology platform that couples high-resolution LC-MS for glycoprotein analysis in regards to COVID-19. (
  • Production of alpha acid samples for use in high pressure liquid chromatography analysis (the current state-of-the-art method) is supervised by an International Subcommittee for Isomerized Hop-α-acids Standards. (
  • The LC-2030C NT is an integrated high-performance liquid chromatography system which prioritizes easy-to-use features for a smooth analysis experience. (
  • The i-Series Method Transfer System enables both conventional analysis via its high compatibility with existing LC systems and rapid analysis via high-speed methods. (
  • The LCMS-2050 provides both high speed and high sensitivity analysis even in a small design. (
  • Improving the detection limits for pesticides, herbicides, flavours and fragrances analysis requires high quality syringe filter products because of the presence of different types of particulates in the samples. (
  • The analysis between three indices and PFT/high-resolution computed tomography (HRCT) showed that prealbumin, albumin and BMI could reflect the PFT and modified Reiff score in non-CF bronchiectasis. (
  • They are ideal for separating more complex mixtures or for applications requiring higher resolution and efficiency. (
  • Detection Devices for Gas Chromatography. (
  • CMBCL houses major equipment for DNA and RNA-based applications, including a BioRad CFX Connect Real-Time PCR Detection System, liquid scintillation counter, lyophilizer and freeze-dryer, cell porator, high-speed and ultra-high-speed centrifuges and ultra-sensitive balances. (
  • In 2003-2004 high performance liquid chromatography electrospry ionization mass spectrometric (LC-ESI-MS/MS) detection (Rybak, M. E. et al. (
  • An optimized sample preparation procedure, involving protein precipitation with acetonitrile followed by mixed-anion exchange solid-phase extraction, allowed for high sensitivity and good peak shape for ß-ODAP detection. (
  • If you are using highly viscous solvents, running at higher temperatures (to reduce mobile phase viscosity) is also recommended. (
  • Nevertheless most small molar mass samples will also profit from higher temperatures and lower flow rates for highly viscous solvents because both approaches increase resolution as a result of better mass transport. (
  • This combination of high pressure liquid chromatography and radioimmunoassay has permitted the identification and quantification of these compounds in extracts of urine, plasma and whole blood from normal individuals. (
  • The Lathyrus sativus extract exhibited the highest vDAO enzyme activity of the extracts, followed by the extract from pea cultivar Amarillo from the Crop Development Centre (CDC). (
  • We have achieved the utmost in both miniaturization and high performance with Shimadzu's technology cultivated over many years of MS development. (
  • Reverse-phase high-performance liquid chromatography using a Nucleosil C-8 column showed that HRA II (the activity eluted at a conductivity of 18-20 mmho on the CM-Sepharose column) eluted as a single sharp peak, the main protein contaminant being cytochrome c, the carrier protein added to enhance the yield of HRA. (
  • High-performance liquid chromatography was found to be a useful analytical tool and may be suitable for the large-scale purification of HRA. (
  • HPL C (High Performance Liquid Chromatography) is a automated high pressure liquid chromatography. (
  • High-Performance Liquid Chromatography Stationary Phases Based on π-π Electron Interaction. (
  • Dive into the research topics of 'High-Performance Liquid Chromatography Stationary Phases Based on π-π Electron Interaction. (
  • Measurements included anthropometric variables, sphygmomanometric and beat-to-beat blood pressure, heart rate (ECG), venous plasma norepinephrine (high-performance liquid chromatography), and efferent postganglionic muscle sympathetic nerve activity (microneurography, peroneal nerve). (
  • IMSEAR at SEARO: A reverse phase high performance liquid chromatography method for simultaneous estimation of melatonin, carbamazepine epoxide and carbamazepine simultaneously in serum. (
  • Serum and hepatic levels of vitamin A were measured by high-performance liquid chromatography. (
  • By combining advanced materials modification capabilities with high-touch consultative engineering, TriStar's enhanced materials team offers a one-stop shop for getting the most possible performance out of critical materials. (
  • Results of blood smear examination, high-performance liquid chromatography, and brain CT scan are shown in Figures 1-3. (
  • It also has complete facilities for cell growth, handling, storage (including cell storage cryo tanks with uninterruptable liquid nitrogen supply), two separate cell culture rooms fully equipped with eight temperature and CO2-controlled cell growth incubators, two biological safety cabinets, and BD Accuri C6 Flow Cytometer and BD FACSJazz cell sorter. (
  • The FCV-32AH is a 2-position 6-port high pressure flow switching valve. (
  • Q. When avoiding high backpressure and shear is it sufficient to run the GPC/SEC at a lower flow-rate (so long as you have enough time) or is larger particle size the better choice? (
  • The overall pressure in a system depends mainly on the flow-rate, mobile-phase viscosity, temperature, inner diameter, number of columns applied, and particle size of the column stationary phase. (
  • For really high molar masses a combination of both large particle sizes and low flow-rate is ideal, if time permits. (
  • Higher pressure differentionals are achievable to overcome resistances to flow caused by high viscosity. (
  • Gas distribution through the manifolds ensures uniform pressure and uniform liquid flow at each SPE tube, even when some positions are open. (
  • Liquid flow rate changes quickly and proportionatly when gas pressure is changed. (
  • The latter can be realised through the high flexibility of flow arrangements which can be established in the SepTor units. (
  • With the advent of ultra-high pressure liquid chromatography (UHPLC) and multidimensional chromatography applications, peak capacities and protein identifications have increased. (
  • For this reason, Chromolith® HighResolution columns offer at least 50% higher efficiency than standard Chromolith® columns (exceeding 140,000 plates/meter [Anthracene]), as well as improved peak shape with excellent symmetry. (
  • Poorly connected fittings have long been recognized as a leading cause of chromatography issues, leading to peak broadening, splitting, and tailing, as well as loss of resolution. (
  • Reversed-phase high-pressure liquid chromatography with gradient elution on Zorbax-ODS columns has been used to separate, identify, and measure, spectrophotometrically, the steroids secreted by both human adrenal and testis cells in primary monolayer culture. (
  • Superficially porous silica columns deliver higher speed and efficiency than fully porous particles of the same size. (
  • Shim-pack XR Series columns use a 2.2 μm packing particle size and offer a skillful balance between resolution efficiency and pressure. (
  • Please note that linear columns are also non-linear at the high and low molar mass end, therefore a different fitting approach is required if samples elute in that region. (
  • The Speedisk 48 pressure processor is designed to process 1, 3 and 6 ml SPE columns in batches of 1 to 48 samples. (
  • The columns are placed under the pressure processor manifold where an inert, dry gas simultaniously and uniformly displaces the liquid that was pipetted down each column. (
  • When used with our BIST™ mobile phases, these ion exchange columns can generate very strong retention of analytes that have the same charge polarity as the stationary phase, unlocking new chromatography applications that were previously too difficult to achieve. (
  • Chromolith® HighResolution RP-18e columns are the ideal alternative to sub 3 µm particulate columns: They generate similar results as columns packed with core-shell particles but at a much lower back-pressure. (
  • Back pressure is higher than with standard Chromolith® columns but still less than half that of any particulate column of the same dimensions. (
  • Because the chemical basis of Chromolith® HighResolution RP-18e columns is identical to that of high-end particulate silica columns (e.g. (
  • Moreover, two or even more Chromolith® HighResolution columns can be easily coupled thanks to the low back pressure. (
  • 25% higher resolution than 100 mm HighResolution columns (depending on application). (
  • The binding of the enalaprilat to the enzyme forms a complex with slow dissociation rate which leads to high influence and long period of action [ 5 ]. (
  • Vegetal diamine oxidase (vDAO), an enzyme proposed to relieve symptoms of histaminosis, shows better reactivity with histamine and aliphatic diamines, as well as higher enzymatic activity than DAO of animal origin. (
  • After chromatography, individual fractions were analyzed by the radioimmunoassay. (
  • Considering the substantial differences in concentrations in blood samples taken from various sites in the body and the high levels in some tissues e.g., in liver, we concluded that the influence of postmortem redistribution should be taken into account in the interpretation of toxicological data when an appropriate peripheral sample cannot be obtained or when blood samples are not available because of putrefaction. (
  • Counter-current ion exchange or chromatography results in high yield, high purity and high product concentrations, at the lowest operational cost when compared to the more conventional stationary bed operations for ion exchange and chromatography. (
  • Chromatography is a way of separating two or more chemical compounds. (
  • For identification of immunoreactive material high pressure liquid chromatography was used to separate these compounds from each other and from known cross-reacting compounds found in physiological specimens. (
  • Students analyse a range of organic salts/compounds in water, using various techniques: UV Visible spectroscopy, High Pressure Liquid Chromatography and Atomic Absorption Spectroscopy. (
  • In addition, high cost and time consuming method further restrains the growth of protein crystallization and crystallography market. (
  • GPC/SEC is often used in quality control (QC), but developing a robust and high-resolution method that delivers precise results, which are reproducible in the long-term, is a challenging task. (
  • Moreover, increasing column length increases resolution due to the higher number of theoretical plates per column. (
  • Antihypertensive drugs are a class of drugs that are used for treating hypertension (high blood pressure) and cardiovascular disease. (
  • Almost half of the U.S. adult population has high blood pressure - or hypertension - and about 20% of these patients have treatment-resistant hypertension. (
  • This column and corresponding adapter entirely eliminate the need for any high-pressure fittings or tubing as well as minimizing all possible dead volumes. (
  • Ultra high-pressure liquid chromatography has become an important analytical tool for meeting these varied needs for higher throughput. (
  • Commonly used to separate, identify, and quantify the individual components of a mixture, liquid chromatography (LC) is a vital tool in the arsenal of analytical techniques used for research and development, as well as quality control across a wide range of industries. (
  • Some fall into the troubleshooting category, others are more about system optimization, but all can have a real impact on the quality of chromatography achieved. (
  • Most of this figure should be pretty self-explanatory, and whilst it is typically used to define the return on investment of a new technology (usually a single product) from a manufacturing business perspective, I believe it's a reasonable surrogate for the life cycle of an enabling technology, such as chromatography. (
  • chromatography technology. (
  • 1 It is recommended to use larger particle sizes when running very high molar mass samples because this will reduce shear. (
  • For lower molar mass samples, where high resolution is required (for example to separate oligomers) the application of larger particles to overcome back pressure issues is not recommended. (
  • These high quality products provide you with optimal filtration and particulate-free samples prior to injection. (
  • VWR supports you in your autosampler vial selection process through on-site consultations with our Chromatography Specialists, and providing samples when needed. (
  • Peptides were ultimately analyzed on a modified (in-house) UHPLC constant pressure system. (
  • Although this grain contains adequate tryptophan, it also contains high levels of leucine, another amino acid that interferes with the enzymatic conversion of tryptophan to niacin. (
  • Estimated and distribution of ethylene oxide have the employment figures were: 1100 ethylene oxide- highest exposure. (
  • Development Strategies for Liquid Chromatography. (
  • AA detects individual chemical elements by measuring the absorption of light by a high-temperature vapor. (
  • It was found that the liquefaction yield of corn stalk in the presence of PG at the optimum temperature of 180 °C was up to 99.2%, which was higher than that of the other three liquefying agents. (
  • Operating conditions such as pressure, temperature and the dimensions of the used tubing are parameters that act in mutual interdependence. (
  • Consequently, a higher temperature results in the reduction of the maximum working pressure, provided the dimensions of the tubing do not change. (
  • With the help of our pressure calculator, you can choose to either calculate the working pressure, the temperature or the required dimensions for your tubing depending on the other two parameters. (
  • All available information on products and materials provided in our online shop, especially regarding chemical resistance as well as pressure- and temperature resistance, are based on our most recent technical knowledge and experience. (
  • Her heart rate is 136 beats/min, blood pressure is 103/62 mm Hg, temperature is 98.06°F (36.7°C), and respiratory rate is 16 breaths/min. (
  • The SepTor systems are currently in use in a large number of pharmaceutical industries for the recovery and/or purification of pharmaceutical intermediates through counter-current ion exchange or chromatography. (
  • Is high hemoglobin a hindrance factor for blood donation? (
  • Compared to those without fibrosis, patients with mild fibrosis (stage F1) had significantly higher levels of secondary BAs, and increased diastolic blood pressure (DBP), alanine aminotransferase (ALT), body mass index, and waist circumstance (WC). (
  • Anthropometry and blood pressure measures were performed and a questionnaire on sleep habits and Epworth Sleepiness Scale were applied. (
  • Urinalysis reveals high specific gravity, proteinuria, red blood cells, and granular and erythrocyte casts. (
  • It differs from Level A because it includes a non-encapsulating, splash-protective, chemical-resistant splash suit that protects against liquids but is not airtight. (
  • When vitamin A intake is low, the absorption efficiency remains high, carotenoid cleavage is enhanced, the plasma transport remains at essentially normal levels, recycling and utilization mechanisms become more efficient, and the excretion of metabolites markedly decreases. (
  • Levels of nitrite (NO 2 − ), a metabolite of nitric oxide ( · NO and inducible nitric oxide synthase (iNOS) are higher in the central nervous system of human PD cases and in animal models of PD [ 6 ]. (
  • In those with excessive daytime sleepiness was observed the highest percentage change in LDL levels, HbA1c and CRP- u, but without statistical significance. (
  • The sst 2 expression is relatively low, likely resulting from downregulating effects of high cortisol levels. (
  • The increased propensity to EDS in childhood sleepiness (EDS) and exercise intolerance, SD and adolescence is due to biological, environmental results in higher adiposity4. (
  • SepTor Technologies is a world-wide leading supplier of the carousel type of simulated moving bed systems for continuous ion exchange and chromatography, under the tradename SepTor. (
  • Feature Papers represent the most advanced research with significant potential for high impact in the field. (
  • 2. The Column in Gas Chromatography Introduction. (
  • 4 The Column in Liquid Chromatography Introduction. (
  • Quantitative Evaluation of Thin-Layer Chromatography. (