Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Pressure: 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)Hydrostatic Pressure: The pressure due to the weight of fluid.Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Chromatography, Affinity: 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)Chromatography, Ion Exchange: 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.Chromatography: 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.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Chromatography, Liquid: Chromatographic techniques in which the mobile phase is a liquid.Kinetics: The rate dynamics in chemical or physical systems.Chromatography, Gas: Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.Molecular Weight: The sum of the weight of all the atoms in a molecule.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.High Pressure Neurological Syndrome: 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, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Lavandula: A plant genus of the LAMIACEAE family.Trypsin: A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.Atmospheric Pressure: The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.Arachidonate Lipoxygenases: 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.- .Amino Acids: 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.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Spectrophotometry, Ultraviolet: Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Lipoxygenase: 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.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Radioimmunoassay: 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.Hydroxyeicosatetraenoic Acids: 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.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Cyanogen Bromide: 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.Rats, Inbred Strains: 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.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Biotransformation: 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.Spectrometry, Mass, Fast Atom Bombardment: A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Solvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Arachidonic AcidsPeptides: 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.Spectrometry, Mass, Electrospray Ionization: A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.Air Pressure: 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.SRS-A: 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)Neurotensin: 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.12-Hydroxy-5,8,10,14-eicosatetraenoic Acid: 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)Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Peptide Mapping: Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Isomerism: The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Oligosaccharides: Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.Rabbits: 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.Ionic Liquids: Salts that melt below 100 C. Their low VOLATILIZATION can be an advantage over volatile organic solvents.Blood Pressure Determination: Techniques for measuring blood pressure.Affinity Labels: 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.Swine: 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).Isoelectric Focusing: 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.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Brain Chemistry: 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.Microsomes, Liver: Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Arachidonic Acid: 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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Cell Line: Established cell cultures that have the potential to propagate indefinitely.TritiumBile: 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.Endopeptidases: A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Dogs: 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)Hypertension: 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.Hydroxylation: Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)Carbon Radioisotopes: Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Protein Conformation: 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).Macromolecular Substances: 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, Pressure: Transducers that are activated by pressure changes, e.g., blood pressure.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Intracranial Pressure: Pressure within the cranial cavity. It is influenced by brain mass, the circulatory system, CSF dynamics, and skull rigidity.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Intraocular Pressure: The pressure of the fluids in the eye.Lysine: An essential amino acid. It is often added to animal feed.Blood Pressure Monitoring, Ambulatory: 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.Liquid Crystals: Materials in intermediate state between solid and liquid.Tandem Mass Spectrometry: A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Cloning, Molecular: 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.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.DNA: 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).Phospholipids: Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Cytochrome P-450 Enzyme System: 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.Species Specificity: 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.Immune Sera: 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.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.Binding, Competitive: 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.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Photobacterium: 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.Chromatography, DEAE-Cellulose: 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)Microsomes: 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)Oligopeptides: Peptides composed of between two and twelve amino acids.Venous Pressure: The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.Protein PrecursorsBrain: 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.Structure-Activity Relationship: 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.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Cells, Cultured: 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.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Isoenzymes: Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Glycopeptides: Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.Adenosine Triphosphate: 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: 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)Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Arterial Pressure: 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.Ventricular Pressure: 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.Heart Rate: The number of times the HEART VENTRICLES contract per unit of time, usually per minute.Mutation: 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.Chromatography, Reverse-Phase: A chromatography technique in which the stationary phase is composed of a non-polar substance with a polar mobile phase, in contrast to normal-phase chromatography in which the stationary phase is a polar substance with a non-polar mobile phase.Uranus: 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.Chromatography, Agarose: 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.Calcium: 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.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Rats, Sprague-Dawley: 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.Manometry: Measurement of the pressure or tension of liquids or gases with a manometer.Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Food Preservation: Procedures or techniques used to keep food from spoiling.Freeze Substitution: 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.Reproducibility of Results: 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.Neptune: 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.Central Venous Pressure: The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.Pulmonary Wedge Pressure: The blood pressure as recorded after wedging a CATHETER in a small PULMONARY ARTERY; believed to reflect the PRESSURE in the pulmonary CAPILLARIES.Antihypertensive Agents: Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.Freezing: Liquids transforming into solids by the removal of heat.Oxygen: 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.Mephenesin: A centrally acting muscle relaxant with a short duration of action.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Germanium: A rare metal element with a blue-gray appearance and atomic symbol Ge, atomic number 32, and atomic weight 72.63.Chromatography, Supercritical Fluid: 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.Drug Stability: The chemical and physical integrity of a pharmaceutical product.Osmotic Pressure: 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: 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)Methods: A series of steps taken in order to conduct research.Synchrotrons: 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.Chromatography, Paper: 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).Phonons: Quanta of acoustic energy which move at the speed of sound.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Systole: Period of contraction of the HEART, especially of the HEART VENTRICLES.Solubility: 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)Vascular Resistance: 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.Protein Denaturation: Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.Food Handling: Any aspect of the operations in the preparation, processing, transport, storage, packaging, wrapping, exposure for sale, service, or delivery of food.Calibration: Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.Hyperbaric Oxygenation: 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.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Enzyme Activation: 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.Evolution, Planetary: Creation and development of bodies within solar systems, includes study of early planetary geology.SepharoseX-Ray Diffraction: 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)Pulse: 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.Proteins: 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.Diastole: Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.Photobiology: The branch of biology dealing with the effect of light on organisms.Phase Transition: A change of a substance from one form or state to another.Biological Assay: 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.Norepinephrine: 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.Calcium Compounds: Inorganic compounds that contain calcium as an integral part of the molecule.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Phycomyces: 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.Reference Standards: A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.Chemical Fractionation: Separation of a mixture in successive stages, each stage removing from the mixture some proportion of one of the substances, for example by differential solubility in water-solvent mixtures. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Iron Compounds: Organic and inorganic compounds that contain iron as an integral part of the molecule.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.Cerebrospinal Fluid Pressure: Manometric pressure of the CEREBROSPINAL FLUID as measured by lumbar, cerebroventricular, or cisternal puncture. Within the cranial cavity it is called INTRACRANIAL PRESSURE.Carbohydrates: 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.Positive-Pressure Respiration: 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.Prospective Studies: 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.Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization: A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.Equipment Design: Methods of creating machines and devices.Sensitivity and Specificity: Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)Fatty Acids: 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)Bacterial Proteins: 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)

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), ...
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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 ...
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 ...
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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 ...
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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.
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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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 ...
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 ...
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.
... : 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
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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 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 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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HPLC ( High Performance Liquid Chromatography )System / India Testing Equipment for sale - Place of Origin: Gujarat India Brand Name: Analytical Technologies Model Number: Intelligent 2230 / 3000 Series Power: Electronic Usage: Pharmaceuticals,Bio-Pharma, Chemicals,Dy... Liquid Chromatography System: Chromatography Sy... HPLC: PREP HPLC PROCESS HPLC: PRODUCTION HPLC ION CHROMATOGRAPHY: GPC Gel Permeation Chromatography: Nano LC
The present study describes a novel sensitive live-cell assay for studying ECE activity. ET-1 is formed from its precursor preproET-1 via the cleavage of the intermediate bigET-1 by ECE-1. However, the subcellular site at which this step occurs is not clear: It could occur intravesicularly along the secretory pathway or bigET-1 may be released and processed extracellularly. To address this point, we have developed an integrated autocrine system.. Until now, ECE activity has been evaluated in solubilized membrane fractions by high-performance liquid chromatography assays,32 immunoassays,12 fluorogenic determinations,33 receptor assays,34 and fluorescence polarization assays.35 Most of these assays require an incubation in vitro with high concentrations of substrate, and all of them need an independent second step to measure the product, ET-1.. In the present study, a recombinant CHO reporter cell line permanently expressing the human ETA receptor and a reporter gene sensitive to its activation ...
A normal-phase Bondapak high performance liquid chromatographic (HPLC) system was compared to two different reversed-phase Bondapak C//1//8 systems for separating and quantifying aldehydes and ketones. In the normal-phase system, isocratic elution with 2-propanol (IPA) and hexane produced the best results. One reversed-phase system consisted of two C//1//8 columns in series. The other reversed-phase system consisted of a single radial compression cartridge (RCC). Both reversed-phase systems employed solvent programming with acetonitrile/water as the mobile phase. Ultraviolet (UV) detection at 340 nm was used in all of the systems.
Increase your HPLC column shelf life with our SiliaChrom Guard Cartridges. Available for all SiliaChrom phases, you will protect your analytical and preparative SiliaChrom HPLC columns. The Guard Cartridges contain the same high quality stationary phase than our SiliaChrom HPLC columns. Choose your convenient Cartridge Holder and proceed your high performance chromatography experiments for an incomparable prolonged time. Save Money and Time, use SiliaChrom Guard Cartridges!
[Incidence of sample storage temperature on HbA 1c determination by high performance liquid chromatography method].: We have evaluated the conservation prior to
LiChrospher is a reliable and versatile traditionally produced spherical silica support. LiChrospher silica is available with a variety of modifications. LiChrospher Si material with no modification is most suitable for normal phase HPLC. LiChrospher Si 60 and Si 100 are versatile HPLC sorbents based on spherical silica particles possessing polar properties. Superspher for highly efficient HPLC of complex mixtures where high peak capacity is required. It improves the separation efficiency of HPLC analysis. This high performance spherical silica carrier with a mean particle size of 4 µm yields the best pressure/separation performance ratio on even the latest generation of HPLC systems and according to theoretical calculation and practical experience.The guaranteed number of theoretical plates for Superspher is , 100.000 N/m. Therefore, they are always first choice if complex mixtures demand high peak ...
The peroxidase was purified by anion exchange high performance liquid chromatography using 50 mM KH-2PO4, pH 7.0, and a linear gradient (0-500 KCl) on a DEAE Poros (4.6 mm/100 mm) column. Figure 1 shows a representative chromatogram for unpurified soybean seed coat SBP extract. The protein was obtained by collecting fractions corresponding to the peak marked "*" in Figure 1. Fractions were pooled using ultrafiltration with a YM10 (Amicon). The salt was removed by washing five times with distilled water from an initial volume of 50 ml to a final volume of 10 ml. 100 l of this final solution were re-injected into the HPLC. The result is shown in Figure 2.. Next, a loading study was performed to determine how much SBP could be purified in one run. Figure 3 shows the results for 20 l, 50 l and 100 l injections. It shows that every time an increasing of SBP was injected, the peak shape was not affected. Therefore, up to an injection volume of 100 l could be purified in one run.. Finally, the purified ...
Semi-preparative high performance liquid chromatography facilities have been developed, capable of separating up to 100mg of material per injection. Stirred slurry column packing techniques were studied in detail. The effects of packing pressure, slurrying solvent, slurry concentration and the duration of the packing process were examined. The optimised packing technique was successfully used to pack columns of 12.5 to 50cm length and 4.9 to 10.9mm internal diameter. Analytical columns (4.9mm I.D.) were packed to evaluate twenty-two commercially available packing materials on a cost-performance basis. Semi-preparative columns (8.1 or 10.9mm I.D.) were packed with materials which gave either high efficiency or showed high performance to cost benefit. The performance of these columns compares favourably with the best results reported in the literature. The sample injection technique was studied using dye mixtures. Experimental results showed that the valve injection technique implemented the full ...
Browse our extensive catalog of new & used Gas Liquid Chromatograph Equipment for sale or auction. Find any required new, refurbished or used Gas Liquid Chromatograph Equipment or device.
Browse our extensive catalog of new & used Gas Liquid Chromatograph Equipment for sale or auction. Find any required new, refurbished or used Gas Liquid Chromatograph Equipment or device.
Present and see the latest results on column technologies, cutting-edge applications & instrumentation, coupling with mass spectrometry and new trends, including microfluidics and nanotechnologies at HPLC 2017 Prague. Click to read more...
A maltogenic amylase (MAG1) from alkaliphilic Bacillus lehensis G1 was cloned, expressed in Escherichia coli, purified and characterised for its hydrolysis and transglycosylation properties. The enzyme exhibited high stability at pH values from 7.0 to 10.0. The hydrolysis of β-cyclodextrin (β-CD) produced malto-oligosaccharides of various lengths. In addition to hydrolysis, MAG1 also demonstrated transglycosylation activity for the synthesis of longer malto-oligosaccharides. The thermodynamic equilibrium of the multiple reactions was shifted towards synthesis when the reaction conditions were optimised and the water activity was suppressed, which resulted in a yield of 38% transglycosylation products consisting of malto-oligosaccharides of various lengths. Thin layer chromatography and high-performance liquid chromatography analyses revealed the presence of malto-oligosaccharides with a higher degree of polymerisation than maltoheptaose, which has never been reported for other maltogenic amylases. The
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Immediately find HPLC and UHPLC columns for reversed phase, chiral, normal phase, GFC, GPC, ion exchange, HILIC, and SFC using our HPLC product search.
Ceratonia siliqua is a typical plant of the Mediterranean area, which is mainly used as animal and human food and in folk medicine for treating some diseases such as antidiarrheal and diuretic. The present study was planned to evaluate the potential of antimicrobial and antioxidant activities of C. siliqua leaves extract and the identification of bioactive compounds by high performance liquid chromatography/mass spectrometry (HPLC/MS) in the active extract. The antioxidant activities of the different organic extracts of C. siliqua were assayed by 2,2-diphenyl-l-picrylhydrazyl (DPPH) and β-carotene tests. Among the tested extracts, results showed that the ethyl acetate extract displayed the greatest DPPH scavenging ability with an IC50 of 1.8 µg/ml and a strong β-carotene bleaching inhibition after 120 min of incubation with an IC50 of 24.01 µg/ml. The investigation of the phenolic and flavonids content showed that the ethyl acetate extract of C. siliqua revealed the highest
Chemicals for high-performance liquid chromatography analyses. (±)-Benzo[a]pyrene-trans-7,8-dihydrodiol (B[a]P-7,8-DHD), (±)-benzo[a]pyrene-trans-9,10-dihydrodiol (B[a]P-9,10-DHD), and (±)-3-hydroxy-benzo[a]pyrene (B[a]P-3OH) were purchased from the National Cancer Institute, Chemical carcinogen Repository (Midwest Research Institute, Kansas City, MO). Methanol was from Lab-Scan (Stillorgan, Ireland). B[a]P was purchased from Sigma (St. Louis, MO).. Genotyping of the CYP1B1 missense mutations. The genomic DNA used was from 116 healthy unrelated Spaniards who participated in a previous study concerning genetic polymorphism in the CYP2A6 gene ( 34). The ethics committee at Karolinska Institutet approved the use of these samples for the current investigation.. Genotyping for CYP1B1, missense mutations in exon 2 (142C , G, 355G , T) and in exon 3 (4326C , G, 4390A , G, 4360C , G), was done using a two-step allele-specific PCR method. For primer sequence and PCR conditions, see ref. 19. In brief, ...
Animals. Female A/J mice were obtained from The Jackson Laboratory (Bar Harbor, ME) at 5 weeks of age and housed according to the guidelines of the Animal Care and Use Committee of the NIH. Mice were fed AIN-93G/M chow from Dyets (Bethlehem, PA) and autoclaved water ad libitum and were weighed weekly. NIH animal facilities are accredited by the Association for Assessment of Laboratory Animal Care. All experiments were carried out under an NIH-approved animal study protocol.. Carcinogen and drug treatment. For the study assessing the effect of rapamycin on established tumors, 25 mice per group were given a single dose of NNK (Toronto Research Chemicals, North York, ON) at 6 weeks of age. For the prevention of tumor development study, NNK was obtained from EaglePicher Pharmaceuticals (Lenexa, KS), and 15 mice per group were treated with three doses of NNK over 3 weeks beginning at 6 weeks of age. The purity of both NNK samples was verified by high-performance liquid chromatography analysis. NNK ...
In HPLC columns, reverse-phase and normal-phase chromatography separation methods are based on polarity. Reverse phase columns separate analytes based on
HPLC Part: AJ0-8639 SecurityGuard™ PREP cartridge for Oligo-WAX 300A Prep HPLC columns with 18.0 to 29.0mm internal diameters (ID), Ea Recomended Use: Column protection for standard HPLC columns Format: Guard Cartridge (e.g. PHE SecurityGuard )
Diluted worts are injected into a high-performance liquid chromatography system. A cation exchange column with water as mobile phase is used to separate the sugars, which are then measured by a refractive index detector. Sugars having a degree of polymerization of 1-3 are quantitatively determined by comparison with aqueous standards containing fructose, glucose, maltose, and maltotriose.. ...
Manufacturer: Agilent; Item ID: 3017815; Warranty: 30-Day Money-Back Guarantee; Description: The Agilent 1100 HPLC System is a modular liquid chromatography system designed to provide precision and
Serum concentrations of vitamins A (retinol) and E (α and γ-tocopherol), two retinyl esters, and six carotenoids (α-carotene, trans-β-carotene, cis β-carotene, β-cryptoxanthin, combined lutein/zeaxanthin, and trans-lycopene) are measured using high performance liquid chromatography with photodiode array detection. A small volume (100 μL) of serum is mixed with an ethanol solution containing two internal standards- retinyl butyrate and nonapreno-β-carotene (C45). The micronutrients are extracted from the aqueous phase into hexane and dried under vacuum. The extract is redissolved in ethanol and acetonitrile and is filtered to remove any insoluble material. An aliquot of the filtrate is injected onto a C18 reversed phase column and isocratically eluted with a mobile phase consisting of equal parts of ethanol and acetonitrile. Absorbance of these substances in solution is linearly proportional to concentration, thus spectrophotometric methods are used for quantitative analysis. Three ...
Determination of sulfonamides by liquid chromatography, ultraviolet diode array detection and ion-spray tandem mass spectrometry with application to cultured salmon flesh
Determination of sulfonamides by liquid chromatography, ultraviolet diode array detection and ion-spray tandem mass spectrometry with application to cultured salmon flesh
Figure 2 Separation of a 1 µL sample injection using UHPLC. A flow rate of 0.8 mL/min, nearly half that of the HPLC separation, was used for elution of the sample using an X-PressPak C18S column with 2 µm particles (2.1 mm i.d. X 50 mm L). This resulted in an analysis time of 1.3 min, approximately 7 times faster than the HPLC separation. The gradient elution program of 1.5 min is 10 times shorter than that for HPLC.. Table II Comparison between UHPLC and conventional HPLC.. Table 2. Comparison between UHPLC and conventional HPLC ...
Several lines of evidence suggest that d-serine, an endogenous agonist of the glycine site on the NMDA receptors, might play a role in the pathophysiology of schizophrenia. The purpose of this study was to determine whether levels of d- and l-serine or d-serine ratio (d-serine/total serine) in cerebrospinal fluid (CSF) were altered in first episode and drug-naive schizophrenic patients. The CSF levels of d- and l-serine in 25 male first episode and drug-naive schizophrenic patients and 17 age-matched male healthy subjects were measured using a column-switching high performance liquid chromatography system. The percentage of d-serine in the total serine of patients was significantly (z = - 2.01, p = 0.044) lower than that of controls. This study suggests that synthetic or metabolic pathways of d-serine may be abnormal in the brain of drug-naive schizophrenic patients, supporting the NMDA receptor dysfunction hypothesis of schizophrenia. © 2005 Elsevier Inc. All rights reserved.. ...
AIMS--To compare high performance liquid chromatography (HPLC) with conventional methods for the estimation of blood haemoglobin A2 (HbA2) and haemoglobin F (HbF) concentrations in routine thalassemia screening. METHODS--An HPLC system (the VARIANT Hemoglobin Testing System) was tested for precision and reproducibility in the measurement of HbA2 and HbF, and reference ranges were obtained for a local healthy adult population. HPLC was compared with column anion exchange chromatography for HbA2 measurement, and radial immunodiffusion, or alkaline denaturation for HbF measurement. The reliability of HbA2 measurement by HPLC for the detection of beta thalassaemia and HbE was assessed in 200 consecutive samples for routine thalassaemia screening. RESULTS--HPLC was rapid, technically easy, and gave good precision and reproducibility. In all comparisons linear regression analysis showed good correlation between HbA2 or HbF concentrations determined by HPLC and by the respective conventional methods. ...
Abstract:. Peptides and proteins are large biomolecules composed of long chains of L -amino acids and plays key functions in the living organisms. A variety of techniques are used to characterize these biomolecules and, among the techniques used, high performance liquid chromatography (HPLC) has been extensively employed both for the preparative as well as the analytical characterization of peptides and proteins. Various HPLC techniques developed for the separation of proteins rely on the differences in the adsorption characteristics, surface charge, ligand specificity, and molecular size of protein molecules. Advancements made in these HPLC techniques have contributed immensely to the development of peptides and proteins based pharmaceuticals. Present article summarizes the principle, methods, and applications of the most common HPLC techniques used in the field of peptides and proteins.. ...
Fast protein liquid chromatography (FPLC) is a liquid chromatography technique for separation of protein molecules under pressure. It differs from high performance liquid chromatography in that the pressures are generally lower, around 435 to 580 psi, compared to 3000-to 5000 psi for an HPLC system.
Background: Chaiqin Qingning Capsule (CQQNC) was a prescription of Traditional Chinese Medicine with the effects of clearing away heat and removing toxin, harmonizing the exterior and interior, it was widely used in Asian, for example, China and Japan, different batches of the raws materials and different processing time may be the vital factor which raised a challenge to control the quality of the CQQNC. Experimental Methods: In this experiment, a high-performance liquid chromatography-mass spectrometry/MS (HPLC-MS/MS) method was developed to simultaneously determine ten bioactive components for the quality control of CQQNC ...
A high sensitivity reversed-phase HPLC method is presented for the simultaneous determination of marker compounds of paracellular transport (atenolol), transcellular transport (propranolol) and P-gp functionality (talinolol) in the Caco-2 system. The Caco-2 system is presently commonly accepted as an in vitro cell culture model of the intestinal mucosa. A programmed wavelength fluorescence detection method was used to optimise the response of the marker compounds. This marker compound mixture and the corresponding HPLC assay can be used for in house validation of the Caco-2 system or to evaluate simultaneously the effect of test compounds or absorption enhancing strategies on monolayer integrity and P-gp functionality. The method can easily be adapted to determine the concentration of atenolol, propranolol and talinolol in blood, thus allowing to use the same compounds in the in situ rat perfusion system with blood sampling from the mesenteric vein ...
Mutalik, S., Hewavitharana, A., Shaw, P. N., Anissimov, Y. G., Roberts, M. S. and Parekh, H. S. (2009) Development and validation of a reversed-phase high-performance liquid chromatographic method for quantification of peptide dendrimers in human skin permeation experiments. Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences, 877 29: 3556-3562. doi:10.1016/j.jchromb.2009.08.039 ...
Food Additives and Contaminants: Part A. 2013;30(1):11-45. Esters of 2 - and 3-monochloropropane-1,2-diol (MCPD) and glycidol esters are important contaminants of processed edible oils used as foods or food ingredients. This review describes the occurrence and analysis of MCPD esters and glycidol esters in vegetable oils and some other foods. The focus is on the analytical methods based on both direct and indirect methods. Methods of analysis applied to oils and lipid extracts of foods have been based on transesterification to free MCPD and determination by gas chromatography-mass spectrometry (indirect methods) and by high-performance liquid chromatography-mass spectrometry (direct methods). The evolution and performance of the different methods is described and their advantages and disadvantages are discussed. The application of direct and indirect methods to the analysis of foods and to research studies is described. The metabolism and fate of MCPD esters and glycidol esters in biological ...
Fittings and tubing comprise a vital, but often ignored portion of the HPLC system. At first glance, the inexperienced eye sees little or no difference between fittings styles and brands. Although these components are not particularly complicated, a solid understanding of their application and use is essential to avoid certain HPLC problems.. ...
Amino acids are very polar compounds which are used as a building blocks in pharmaceutical industry. They are widely used as supplements and food additives. Depending on the pH of the mobile phase they can exist in acidic, basic or zwitter-ionic form. At pH below 3, amino acids are basic in nature and have the highest hydrophobicity. Within pH of 3 to 7 amino acids are in zwitter-ionic form where they are the most hydrophilic. There is no mechanism of retention on reversed-phase column and amino acids are not retained. Bufferless ion-separation (BLIS) was introduced by SIELC as a way to retain and analyze amino acids in reversed-phase cation-exchange mode. This mode allows to analyze amino acids as zwitter-ions without any ions/buffers in the mobile phase. The method was adopted for analysis of amino acids on core-shell mixed-mode columns. A similar approach on a reversed-phase core-shell column results in distorted peaks and no separation or significant retention to achieve baseline separation. ...
A straightforward and available reversed-phase high performance liquid chromatography (HPLC) method with UV detection has been developed and validated for mycophenolic acid (MPA) A-770041 assay in human plasma. with enough accuracy and precision. The method showed significant linear response-concentration relationship throughout the MPA concentration range of 0.2-10 μg/ml. A typical linear regression equation of the method was: y = 8.5523 A-770041 x + 0.094 with x and y representing MPA concentration (in μg/ml) and peak height respectively and the regression coefficient (r) of 0.9816. The average within-run and between-run variations of 7.81 and 4.78 percent. The average drug recovery from plasma was 95.24 percent throughout the linear concentration range. The limits of detection (LOD) and quantitation (LOQ) of the method were 0.05 and 0.2 μg/ml respectively. The practical applicability of the method was proven throughout a bioequivalence study. The results showed the acceptable degree of ...
High-Performance Liquid Chromatography (HPLC), a chromatographic technique is used to identify, quantify and separate each component from a sample of complex chemical mixtures. Presently, HPLC is a versatile technique, available for analyzing all types of biological compounds that can be isolated or synthesized. This method involves the passage of liquid sample over solid adsorbent material packed in a column with solvent. HPLC technique has been used in various fields such as legal, medical, manufacturing processes and in research. This technique relies on pumps and other accessories to pass the sample through the column filled with sorbent (active ingredient of the column). HPLC is highly efficient and different from the conventional liquid chromatographic methods in terms of high operational pressures used in HPLC to run the mobile phase through the column. In addition, the resolution power of HPLC used during separation is higher when compared to conventional liquid chromatographic ...
The normal phase of iron is as a lustrous, gray, solid metal. Its melting point is 2800 degrees Fahrenheit, and its density is 7874 kg m-3. Like many metals, it is able to be hammered into thin...
Nova-Pak HR Silica columns are silica-based, semi-preparative and preparative columns that are based on 6 µm particle technology. Compared to a 5 µm column, Nova-Pak HR columns offer higher resolution, more efficient separations, and faster chromatography.
Non-covalent immobilized artificial membrane reverse-phase high performance liquid chromatography was previously evaluated as a means whereby elution times for antimicrobial peptides from columns mimicking the lipid bilayers of different membrane systems might be used as a fast-screening method to compare relative binding effectiveness. Such a system would aid in the development of antimicrobial peptides that bind preferentially to model pathogenic systems and leave the hosts membranes reasonably unaffected. A non-covalent approach allows for flexibility in membrane composition but was found to be inadequate for analysis of most peptides due to significant lipid loss at high acetonitrile concentrations. A covalent approach where phosphatidylcholine was amide-linked to the silica surface was examined to evaluate its use as a fast-screening method and compare its data to that collected from the non-covalent columns. Initial work with a 1-cm column proved ineffective due to problems with balancing ...
BioSuite™ Peptide Analysis columns consist of two premier reversed-phase column chemistries specifically optimized for peptide mapping from simple to complicated digests. BioSuite PA Columns are available in various configurations for LC or LC/MS applications, including 250 mm lengths for ultra high resolution. These BioSuite™ PA-A and PA-B columns provide excellent batch-to-batch reproducibility for consistent results and are uniquely QC tested specifically for peptide mapping. BioSuite™ C18 3µm PA-A is a100Å, difunctional bonded, low ligand density, silica-based reverse-phase column and BioSuite™ C18 3.5µm PA-B is a 300Å, high ligand density, monofunctional, silica-based reverse-phase column.
HPLC Column Configurator helps you save up money & time. Find and compare HPLC columns specifications, manufacturers, prices, application methods, etc.
Thermo Fisher Scientific Inc., the world leader in serving science, today announced that it will feature its Thermo Scientific Dionex UltiMate 3000 Biocompatible Rapid Separation (BioRS) liquid chromatography system during Pittcon 2013. This system is designed to combine the performance advantages of ultrahigh-performance liquid chromatography (UHPLC) with the corrosion resistant flow path demanded by the analysis of proteins, peptides, nucleic acids and biotherapeutics. Thermo Fisher wi
A sensitive, simple and rapid method without sample pretreatment is presented for the simultaneous determination of flunitrazepam and its main metabolites (norflunitrazepam, 7-amino- and 7-acetamidoflunitrazepam) in urine. The single-step procedure i
Catecholamines and their metabolites have been separated isocratically by reverse-phase chromatography with aqueous (no organic solvent admixed) eluents. Unlike ion-exchange or ion-pair chromatography, mixtures of both acidic and basic substances can be separated in a single chromatographic run, because the retention is governed by hydrophobic interactions between the nonpolar moiety of the solute molecules and the octadecyl-silica stationary phase. The relative retention values strongly depend on the pH of the eluent, which governs the degree of dissociation of ionogenic solutes. The reproducibility of the results and the stability and efficiency of the chromatographic systems make this approach particularly attractive for use in clinical analysis.. ...
Chlrorophylls and their Degradation Products using High Performance Liquid Chromatography (HPLC), with Data from Suspended and Sinking Particulate Matter in Prydz Bay, Antarctica - chlorophyll;chlorophyllide;phaeophorbide;sediment trap;HPLC;Prydz Bay;flux;
Higher value products demand for chromatographic techniques. The techniques are used for. concentration, de salting and purification of protein preparation. When choosing a chromatographic. technique, a number of factors need to be put into consideration. These factors may include iso-. electric point, biological affinity, hydro-phobicity and molecular weight in proteins. Each of the above. properties can be exploited by different specific chromatographic methods. The following are the. chromatographic parameters that need to be considered; recovery, capacity and resolving power.. The following are different types of chromatography used in downstream processing.  Adsorption chromatography.  Affinity chromatography.  Gel filtration chromatography.  Ion exchange chromatography.  High performance liquid chromatography.  Distillation.  Ion exchange chromatography. In adsorption chromatography, separation is done according to affinity of protein or any other. material. Affinity ...
LC1620A HPLC (high performace Liquid Chromatography) instrument system with HPLC column, US $ 2,000 - 10,000 / Set, Zhejiang, China (Mainland), westtune, LC1620A.Source from Hangzhou West Tune Trading Co., Limited on Alibaba.com.
Sujatha, * and Rai, Lavanya and Kumar, Prathap and Krishnand, BR and Mahato, KK and George, Sajan D and Kartha, VB and Santhosh, C (2007) Protein profile study of Pap smear and cervix biopsy tissues using High Performance Liquid Chromatography (HPLC) - Laser Induced Fluorescence (LIF). In: First Asian Spectroscopy conference & Asian Biospectroscopy Conference (ASC-07),,, 29th January - 2nd February 2007, 221-222., Bangalore,. (Submitted) ...
High performance liquid chromatography (HPLC) spectra of surfactin (dashed line) and surfactin-(Glu-γ, Asp-β)-hexyl ester (solid line) under the same conditio
BACKGROUND: Biochemical measurement of fat-soluble vitamins would allow direct assessment in epidemiological studies of their association with disease. However, the perceived instability of these compounds and typically high cost of collection and analysis may make their measurement impractical, particularly in large-scale studies. Using a high performance liquid chromatography assay developed in-house, we have investigated the separate effects of temperature and light on the stability of vitamins in whole blood over several days. METHODS: Multiple blood samples from 10 volunteers were stored at 20 degrees C or 4 degrees C and in dark or light conditions. Immediately after collection and 1, 2, 3, 4, and 7 days later, samples stored under each condition were centrifuged, and the plasma was aliquoted and stored at -80 degrees C. Subsequently, all aliquots from each individual were analysed in one analytical run. RESULTS: In whole blood stored under any of the four conditions for up to 7 days,
Photolysis of r-1,c-2,t-3,t-4-tetraphenylcyclobutane: quantum yield determinations via high performance liquid chromatography | R.B. Frings; W. Schnabel | download | BookSC. Download books for free. Find books
UCL Discovery is UCLs open access repository, showcasing and providing access to UCL research outputs from all UCL disciplines.
This study was aimed to investigate the anticancer activities and the mechanism of the anticancer activities of a novel anticancer agent - 2-acetylamino-3-[4-(2-acetylamino-2-carboxyethylsulfanylthiocarbonylamino)phenylthiocarbamoylsulfanyl]propionic acid (2-AAPA). 2-AAPA was found to inhibit various human cancer cell lines with a narrow range of IC50 values (28-75 μM). These cell lines include lung (NCI-H226), prostate (PC-3), breast (MCF-7), skin (A431), melanoma (UACC-62 and SK-MEL-2), and renal (UO-31) cancers, as well as human ovarian cancers (OVCAR-3 and NCI/ADR-RES) which are resistant toward doxorubicin. Flow cytometric studies revealed that 2-AAPA induced cell cycle arrest at G2/M phase and produced significant cell apoptosis in UACC-62 cells. Through immunofluorescence studies, 2-AAPA was found to depolymerize microtubules and cause cell morphological change. An HPLC (high performance liquid chromatography) assay demonstrated that proteins were glutathionylated in both OVCAR-3 and ...
In Agilent Technologies Deutschland GmbH v Waters Corp and another (spotted by LexisNexis subscription-only All England Direct service) [2004] EWHC 2992 (Ch) Mr Justice Pumfrey, sitting in the Patents Court, dismissed what looked like a pretty far-out patent infringement claim. Agilent owned a patent for to pumping apparatus for the delivery of liquid at high pressure which could be used in high pressure liquid chromatography columns. Following unreported proceedings in which the Court of Appeal ([2002] All ER (D) 152 (May)) held the patent valid and infringed, Agilent sued again, alleging that another Waters pump system infringed. This machine operated in manual mode,the operator selecting pump volume from four pre-selectable volumes and separately specifying the flow rate of solvent delivered by the machine. This machine informed the operator if it could not deliver the specified flow rate at the volume specified but did not automatically change the range. Waters maintained that automatic ...
Pravadali, Sercan, Bassanese, Danielle N., Conlan, Xavier A., Francis, Paul S., Smith, Zoe M., Terry, Jessica M. and Shalliker, R. Andrew 2013, Comprehensive sample analysis using high performance liquid chromatography with multi-detection, Analytica chimica acta, vol. 803, pp. 188-193, doi: 10.1016/j.aca.2013.08.013. ...
[96 Pages Report] Check for Discount on United States High-performance Liquid Chromatography (HPLC) Market Report 2017 report by QYResearch Group. In this report, the United States High-performance Liquid Chromatography (...
Lab Manager features articles relating to management, technology, and equipment common to laboratories in industry, medicine, universities, and
|p|Silia|em||span style=color: #46423c;|Chrom|/span||/em||sup|®|/sup| XDB1 NH2 is a very versatile stationary phase which can be used in normal phase, reverse phase or ion exchange conditions as a weak anionic exchanger (WAX).|/p|
Specialised Conductives Pty. Ltd. was established in 1987 to sell nickel particulates for EMI paint coatings to shield electronics. In the 1990s, it acquired a number of agency product lines from USA, UK and elsewhere. Now, Specialised Conductives provides a range of materials for EMI shielding and ESD applications, ferrites and Zippertubing jackets for cables and stainless steel fibres for conductive plastics . The company also supplies specialty high pressure liquid chromatography columns for medical research. On July 1st, 2010, the part of the company importing high performance metal flakes for coatings and metal finishing and stainless steel fibres for conductive plastics was sold to Australian Metal Powders Supplies ...
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Free Online Library: Rapid quantification of resveratrol in mouse plasma by ultra high pressure liquid chromatography (UPLC) coupled to tandem mass spectrometry.(FULL-LENGTH ARTICLES, Report) by Puerto Rico Health Sciences Journal; Health, general Fluorides High performance liquid chromatography Mass spectrometry Resveratrol
By employing science and nature in a smart, innovative way, were able to take your dream and design a superior product that performs. Analytical testing in our in-house lab during all stages of production verifies an ingredients fingerprint - this is achieved through a highly accurate infrared spectrometer, plus high-pressure liquid chromatography analysis. Using the intelligence found in premium organic botanicals, our skilled team of chemists and product developers monitor every step of the process. We guarantee that our formulas comply with all recognized standards, as well as our clients requirements ...
Roswit W.T., McCourt D.W., Partridge N.C., Jeffrey J.J.. Two protein inhibitors of metalloproteinases (TIMP) were isolated from medium conditioned by the clonal rat osteosarcoma line UMR 106-01. Initial purification of both a 30-kDa inhibitor and a 20-kDa inhibitor was accomplished using heparin-Sepharose chromatography with dextran sulfate elution followed by DEAE-Sepharose and CM-Sepharose chromatography. Purification of the 20-kDa inhibitor to homogeneity was completed with reverse-phase high-performance liquid chromatography. The 20-kDa inhibitor was identified as rat TIMP-2. The 30-kDa inhibitor, although not purified to homogeneity, was identified as rat TIMP-1. Amino terminal amino acid sequence analysis of the 30-kDa inhibitor demonstrated 86% identity to human TIMP-1 for the first 22 amino acids while the sequence of the 20-kDa inhibitor was identical to that of human TIMP-2 for the first 22 residues. Treatment with peptide:N-glycosidase F indicated that the 30-kDa rat inhibitor is ...
Extracts for phenolic quantitation were prepared with 25 mg of finely ground, freeze-dried tissue and extracted three times sequentially in a total volume of 4.5 mL of 100% HPLC-grade methanol by sonication. Extracts were centrifuged for 10 min at 13,000 rpm, and the supernatant was dried in an SC110A SpeedVac Plus concentrator. Dried extracts were resuspended in 300 µL of 100% methanol, and chlorophyll was removed using Strata-X 33-µm solid-phase extraction columns (Phenomenex). The column was conditioned with 3 mL of 100% methanol and then 3 mL of deionized water before applying sample and eluting phenolics with 9 mL of 100% methanol. Extracts were again dried in glass tubes in an SC110A SpeedVac Plus concentrator, weighed, and resuspended in 100% methanol to 10 mg mL−1. Each sample (20 µL) was analyzed using an HPLC system (Beckman Coulter System Gold 126 solvent module with a System Gold 168 diode array detector) equipped with a Phenomenex Kinetex C18 column (150 × 4.6, 2.6 µm; 100 ...
The test the FDA uses to certify each batch of these dyes before they legally may be used in drugs and cosmetics marketed in the United States no longer will be done by visible spectrophotometry, but by reversed-phase high performance liquid chromatography ...
A recent study, performed by Lokiec et al. (16) , on a 53-yr-old female patient treated with CPT-11 for liver metastatic colon carcinoma, showed eight urinary metabolites: six compounds were already known, namely SN-38-G, SN-38, APC, NPC, RPR112524 (5 hydroxy-CPT-11), and RPR112526 (decarboxylation of the acid form of the lactone ring of CPT-11). In addition, HPLC profiles showed the presence of unknown metabolites, M1 and M2 (16) .. In urines of two children and two adults treated by CPT-11 the same metabolites were recovered: SN-38, SN-38-G, APC, NPC, and three unknown metabolites (M1, M2, and M3) were detected by HPLC coupled to fluorescence detection. We identified metabolites M1 and M2: these two compounds had a molecular mass of 602, resulting, respectively, from a monohydroxylation either on the CPT ring or the terminal piperidine. According to its HPLC retention time and its fragmentation mass spectrum, the structure of M1 is different from that of the standard derivative RPR112524, ...
TY - JOUR. T1 - Quantification of sunitinib in human plasma by high-performance liquid chromatography-tandem mass spectrometry. AU - Minkin, Patton. AU - Zhao, Ming. AU - Chen, Zhaoyuan. AU - Ouwerkerk, Jan. AU - Gelderblom, Hans. AU - Baker, Sharyn D.. PY - 2008/10/15. Y1 - 2008/10/15. N2 - A rapid, sensitive and specific method was developed and validated using LC/MS/MS for determination of sunitinib in human plasma. Sample preparation involved a liquid-liquid extraction by the addition of 0.2 mL of plasma with 4.0 mL tert-butyl-methyl-ether extraction solution containing 25 ng/mL of the internal standard clozapine. Separation of compounds was achieved on a C18 (50 mm × 2.1 mm i.d., 3.5 μm) analytical column using a mobile phase consisting of acetonitrile/H20 (65:35, v/v) containing 0.1% formic acid and isocratic flow at 0.150 mL/min for 3 min. The analytes were monitored by tandem-mass spectrometry with electrospray positive ionization. Linear calibration curves in human plasma were ...
A new method for the analysis of phospholipids by normal-phase HPLC is described using a silica column. Addition of ammonia and triethylamine to a gradient based on chloroform/methanol/water promoted a good and rapid separation of phospholipid classes (20min run). The use of an evaporative light scattering detector permitted an accurate analysis of a mixture of phospholipids. Calibration curves were linear within different range for each phospholipid class. The LOD and LOQ obtained were below 0.03 and 0.05mgkg-1 for all cases, respectively. Besides, a new method for the separation of phospholipids from total lipids before HPLC analysis by a solid-phase extraction (SPE) with Si cartridges has been developed. This methodology gave a good recovery ranging from 97 to 117%. The method was validated with a standard mixture of phospholipids. This method has been applied to characterize the phospholipid fraction of subcutaneous fat from Iberian pig. Cardiolipin, phosphatidylethanolamine, ...
TY - JOUR. T1 - Optimized extraction of phospholipids and lysophospholipids for nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry. AU - Byeon, Seul Kee. AU - Lee, Ju Yong. AU - Moon, Myeong Hee. PY - 2012/1/21. Y1 - 2012/1/21. N2 - The efficiencies of four different methods for the extraction of phospholipids (PLs) and lysophospholipids (LPLs) from human plasma samples were examined by comparing extraction recovery values using nanoflow liquid chromatography-electrospray ionization-mass spectrometry (nLC-ESI-MS). For recovery measurements, six PL and six LPL standards of different head groups were spiked into a human plasma sample, and the peak areas of each individual species after extraction were measured from the chromatograms of the nLC-ESI-MS runs. Recovery was calculated by comparing the peak area of an extracted standard species with that of the same species spike after extraction of the same plasma sample. For lipid extraction, four different extraction ...
TY - JOUR. T1 - Comparison of gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry methods to quantify α-tocopherol and αtocopherolquinone levels in human plasma. AU - Mottier, Pascal. AU - Gremaud, Eric. AU - Guy, Philippe A.. AU - Turesky, Robert J.. PY - 2002/2/1. Y1 - 2002/2/1. N2 - Two mass spectrometric methods were established for the quantitative analyses of α-tocopherol (TH) and its oxidation product α-tocopherolquinone (TQ) in human plasma. Both methods make use of isotopically labeled internal standards of different levels of deuteration (d3-TH and d6-TQ). Plasma (100 μl) was saponified in the presence of a mixture of antioxidants, and then TH and TQ were extracted with hexane. With the GC-MS method, the analytes were first converted into O-trimethylsilyl derivatives before analysis in the selective ion monitoring mode. The derivatization procedure led to the quantitative conversion of TQ into the O-trimethylsilyl derivative of ...
Abstract: A liquid chromatography tandem mass spectrometry method was developed for quantifying ten cannabinoids in oral fluid (OF). This method utilizes OF collected by the Quantisal device and concurrently quantifies cannabinol (CBN), cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-THC (11-OH-THC), 11-nor-9-carboxy-Δ9-THC (THC-COOH), 11-nor-9-carboxy-Δ9-THC glucuronide (THC-COOH-gluc), Δ9-THC glucuronide (THC-gluc), cannabigerol (CBG), tetrahydrocannabiverin (THCV), and Δ9-tetrahydrocannabinolic acid A (THCA-A). Solid phase extraction was optimized using Oasis Prime HLB 30 mg 96-well plates. Cannabinoids were separated by liquid chromatography over a BEH C18 column and detected by a Waters TQ-S micro tandem mass spectrometer. The lower limits of quantification (LLOQ) were 0.4 ng/mL for CBN, CBD, THC, 11-OH-THC, THC-gluc, and THCV; and 1.0 ng/mL for THC-COOH, THC-COOH-gluc, CBG and THCA-A. Linear ranges extended to 2000 ng/mL for THC and 200 ng/mL for all other analytes. ...
Feijoa fruit is becoming increasingly popular, yet limited studies have focused on the antioxidant capacity and phenolic profiling of its extracts. In this research, optimization of phenolic extraction from feijoa flesh, peel, and whole fruit from four New Zealand grown cultivars was conducted using orthogonal design. Antioxidant activities of the extracts were assessed, followed by phenolic profiling by a validated liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method. For feijoa flesh and whole fruit, the extraction was optimized using 70% ethanol, material to solvent ratio of 1:30, at extraction temperature of 50 °C for 30 min. For feijoa peel, extraction at 50 °C for 60 min using 50% ethanol with a material to solvent ratio of 1:30 were the optimized conditions. Results showed feijoa peel had higher total phenolic content (TPC) and antioxidant activities than the flesh and whole fruit. Overall, the Unique cultivar had a relatively higher TPC and ...
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Amphetamine, methamphetamine, illicit designer phenethylamines (MDA, MDEA, MDMA, MBDB, and BDMPEA), and other phenethylamines (benzyl-1-phenylethylamine, cathinone, ephedrine, fenfluramine, norfenfluramine, phentermine, 1-phenylethylamine, phenylpropanolamine, and propylhexedrine) were extracted from serum using a solid-phase extraction procedure. The extracts were examined with high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). The drugs were separated on ODS column in acetonitrile/50mM ammonium formate buffer (pH 3.0) (25:75) as a mobile phase. Full-scan mass spectra of drugs examined by means of APCI with collision-induced dissociation showed protonated molecular ions and fragments typical for particular drugs. LC-APCI-MS allowed an unequivocal differentiation of all drugs involved. The quantitation was performed using selected ion monitoring of protonated molecular ions and fragments of drugs involved and their deuterated ...
In this study, a modified on-column frit preparation method for fused silica capillaries was used to analyze a venom mixture which contained the milkings from approximately ten snakes of the Agkistrodon contortrix contortrix (southern copperhead) species. One hundred and twenty-three proteins were identified by in-gel digestion coupled with nano-HPLC MS. Among them, twenty proteins matched the references and databases identified as snake venom proteins. In addition, de novo sequencing is applied to analyze the collision-induced dissociation (CID) data generated by in-solution digestion coupled with nano-HPLC MS. Twenty-three proteins matched the databases and references previously identified as snake venom proteins.; Because of insufficient sequences in the database, many peptides and hypothetical proteins could not be matched to the venom proteins. Some venom proteins we identified were found in other species. To build up an intact knowledge base to help toxicant study and clinical treatment, ...
Lauback, Ronald; Lauback, RG (1982). "High-Pressure Liquid Chromatography". Journal of Liquid Chromatography & Related ... examples: "High-Pressure Liquid Chromatography Assay for Dane Salt Potassium(-)-N-(1-Methoxycarbonylpropene-2yl)-p- ... Lauback, Ronald (1984). "High-Performance Liquid Chromatographic". Journal of Liquid Chromatography & Related Technologies. 7: ... Journal of Liquid Chromatography & Related Technologies, Volume 5, Issue 7 1982). "Specific High-Performance Liquid ...
"Reversed-phase high-pressure liquid chromatography of some tryptamine derivatives." Journal of Chromatography 157:365-370. ...
Evans, MA; T Morarity (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. doi:10.1126/ ... and for high performance liquid chromatography (HPLC) Zare is also involved in the development of desorption electrospray ... Snyder, KL; Zare, RN (1 July 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 ...
"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 ... which has high theanine content.[10] Theanine is substantially present in black, green, and white teas from Camellia sinensis ... or urinalysis in rats fed high doses of theanine for 13 weeks.[42] Large studies in humans have not been undertaken; however, ...
The nebulization is accomplished by pumping a liquid sample at moderately high pressure through an electrothermally heated ... It transfers ions from the liquid phase to the gas phase for analysis. It is particularly useful in liquid chromatography-mass ... Gelpí E (1995). "Biomedical and biochemical applications of liquid chromatography-mass spectrometry". Journal of Chromatography ... Thermospray was originally developed for coupling liquid chromatography to mass spectrometry (LC-MS). Thermospray is the ...
"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. Zhang, A.; ...
"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 ... which has high theanine content. Theanine is substantially present in black, green, and white teas from Camellia sinensis in ... blood pressure control, and mood improvement as "unclear or conflicting scientific evidence" and the evidence for improved ...
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 ...
"Trace analysis of peroxide explosives by high performance liquid chromatography-atmospheric pressure chemical ionization-tandem ... high performance liquid chromatography/mass spectrometry (HPLC/MS),[19][20][21][22][23] and HPLC with post-column ... High / moderate when wet. Detonation velocity. 5300 m/s at maximum density (1.18 g/cm3), about 2500 - 3000 m/s near 0.5 g/cm3. ... Several methods can be used for trace analysis of TATP,[13] including gas chromatography/mass spectrometry (GC/MS),[14][15][16] ...
"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 ... Studies on test rats have shown even repeated, extremely high doses of theanine cause little to no harmful psychological or ... which has high theanine content.[10] Theanine is substantially present in black, green, and white teas from Camellia sinensis ...
"Trace analysis of peroxide explosives by high performance liquid chromatography-atmospheric pressure chemical ionization-tandem ... including gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography/mass spectrometry (HPLC/MS), and ... "Analysis of triacetone triperoxide by gas chromatography/mass spectrometry and gas chromatography/tandem mass spectrometry by ... It is also able to evade detection because it it is one of the few high explosives that do not contain nitrogen-and can ...
Dhalwal K.; Shinde V.M.; Biradar Y.S.; Mahadik K.R.; 2008 High pressure liquid chromatographic determination of bergenin and ... and gallic acid from Bergenia ciliata and Bergenia ligulata by using thin-layer chromatography. ...
In order to withstand the pressure, a new field of chromatography came into being: UHPLC or UPLC- ultra high pressure liquid ... A monolithic HPLC column, or monolithic column, is a column used in high-performance liquid chromatography (HPLC). The internal ... 17). "SilicaRODTM A new challenge in fast high-performance liquid chromatography separations." Trends in Analytical Chemistry, ... Perfusion chromatography showed, for the first time, that chromatography media could support high flow rates without ...
... gas chromatography or high-performance liquid chromatography in order to achieve a multi-dimensional separation. They come in ... Ambient pressure methods allow for higher resolving power and greater separation selectivity due to a higher rate of ion- ... gas chromatographs and high-performance liquid chromatography setups. IMS is a widely used technique, and improvements and ... Systems operated at higher pressure (i.e. atmospheric conditions, 1 atm or 1013 hPa) are often accompanied by elevated ...
... 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.. ... high sensitivity screening can be obtained utilizing SWV. For this reason, squarewave voltammetry has been utilized in numerous ...
The most common technique for measuring molecular mass used in modern times is a variant of high-pressure liquid chromatography ... High Number-Average Molecular Mass Polymers may be obtained only with a high fractional monomer conversion in the case of step- ... HPLC) known by the interchangeable terms of size exclusion chromatography (SEC) and gel permeation chromatography (GPC). These ... The limited accessibility of stationary phase pore volume for the polymer molecules results in shorter elution times for high- ...
... high pressure liquid chromatography, and gas phase peptide sequencing suggested that Lys-69 and Cys-360 are covalently bound to ... The inhibition of the formation of polyamines by ODC activity can be ameliorated by dietary and bacterial means because high ... It has been noted that ornithine decarboxylase (ODC) exhibits high activity in tumor cells, promoting cell growth and division ... However, since African trypanosomiasis has a high mortality rate if left untreated, treatment with eflornithine may justify any ...
... derivatization with 9-xanthydrol followed by high-pressure liquid chromatography (HPLC) with fluorescence detection and even ... Other methods also make use of SPE, but use gas chromatography with mass spectrometry (MDGC/MS) and liquid chromatography with ... Miniaturized liquid-liquid extraction (mLLE) followed by LC-MS/MS can be used to determine EC in wine, without using ... Several extraction and chromatographic techniques have been used, including continuous liquid-liquid extraction (LLE) with ...
... high pressure liquid chromatography, thin layer chromatography, and mass spectrometry have been used to detect cicutoxin but ... Cardiovascular symptoms include alternating slow or fast heart rate and alternating low and high blood pressure. Other cardiac ... High doses of anticonvulsant medicine are often required to halt seizure activity and further medical care including intubation ... Low blood pressure is usually treated with intravenous fluid replacement, but the administration of dopamine or norepinephrine ...
... high pressure liquid chromatography, and formulation of the Rootare-Prenzlow Equation. Rootare was born and raised in Tallinn, ...
Stalkup's PhD dissertation was, "The Study of High Pressure Vapor-Liquid Equilibria by GasLiquid Partition Chromatography". ... After graduation from high school in Waco, Texas, he was admitted to Rice University where he earned the Bachelor of Arts ...
PtdIns5P was first demonstrated by HPLC (high pressure liquid chromatography) in mouse fibroblasts as a substrate for PtdIns(4, ... PtdIns5P is of similar or higher abundance as compared to PtdIns3P and ~20-100-fold below the levels of PtdIns4P ( ... steady-state PtdIns5P levels are more than 5-fold higher than those of PtdIns(3,5)P2. ...
... ion exchange chromatography cannot be used, and thin layer chromatography or high-pressure liquid chromatography should be used ... Its advantages include i) the frequency of Lys and Arg residues in proteins, ii) the high specificity of the enzyme, iii) the ... An example of the ion-exchange chromatography is given by the NTRC using sulfonated polystyrene as a matrix, adding the amino ... The derivatized amino acids are subjected to reversed phase chromatography, typically using a C8 or C18 silica column and an ...
... 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. Typically it is given by injection under the skin, but ... It is simply a nuisance for patients to inject whenever they eat carbohydrate or have a high blood glucose reading. It is ...
... medium-pressure liquid chromatography, "flash" chromatography, open-column chromatography, vacuum-liquid chromatography (VLC), ... fractionation are solvent-solvent partitioning and chromatographic techniques such as high-performance liquid chromatography ( ... Countercurrent chromatography (CCC) is particularly well-suited for bioassay-guided fractionation because, as an all-liquid ... Herbalists assert that as phytopharmaceuticals rely upon synergy for their activities, plants with high levels of active ...
... from retinol in serum and other tissues and quantified with the use of methods such as high-performance liquid chromatography.[ ... Increased intracranial pressure manifesting as cerebral edema, papilledema, and headache[4] (may be referred to as Idiopathic ... Cod liver oil is particularly high in vitamin A.. *Medications - at high doses of vitamin A - are often used on long-term basis ... Diet - liver is high in vitamin A. The liver of certain animals - including the polar bear, bearded seal,[24][25] walrus,[26] ...
... of the mobile phase additives on sensitivity in the analysis of peptides and proteins by high-performance liquid chromatography ... Electrospray ionization has also been achieved at pressures as low as 25 torr and termed subambient pressure ionization with ... Ramanathan R, Zhong R, Blumenkrantz N, Chowdhury SK, Alton KB (October 2007). "Response normalized liquid chromatography ... Pitt, James J (February 2009). "Principles and Applications of Liquid Chromatography-Mass Spectrometry in Clinical Biochemistry ...
PRWEB) September 10, 2014 -- The European Supercritical fluid chromatography reagents report defines and segments the concerned ... It exhibits properties such as low viscosity and high diffusivity, which makes it is suitable for use as a mobile phase in ... chromatography. At the critical point, the substance cannot be distinguished as a gas or liquid phase, as it can diffuse ... A super critical fluid is a substance that can withstand temperature and pressure that is beyond its critical point. ...
... of chromatography in which the liquid mobile phase is forced through a column of solid stationary phase under high pressure ... ... of chromatography in which the liquid mobile phase is forced through a column of solid stationary phase under high pressure ... ... high-pressure-liquid-chromatography definition: Noun 1. (chemistry) A form ... high-pressure-liquid-chromatography definition: Noun 1. (chemistry) A form ...
High Pressure Liquid Chromatography Resolution Factor Platelet Free Plasma High Pressure Liquid Chromatography Grade High ... Mourits-Andersen T., Jensen R., Dyerberg J. (1985) High Pressure Liquid Chromatography-125J-RIA, A Sensitive and Specific ... High Pressure Liquid Chromatography-125J-RIA, A Sensitive and Specific Prostaglandin Assay. ... Skrinska, V., 1983, High-performance liquid chromatography of prostacyclin, J of Chromatography, 277: 287.CrossRefGoogle ...
High pressure liquid chromatography) Biochemist analyses a new compound synthesized by microcide chemists for its interaction ... High pressure liquid chromatography) Biochemist analyses a new compound synthesized by microcide chemists for its interaction ... Keywords: biochemist, biomedical research, chemist, chemistry, female, high pressure liquid chromatography, hplc, ... Licence fees: A licence fee will be charged for any media (low or high resolution) used in your project. ...
High-pressure liquid chromatography (HPLC) is a method used in chemistry and biochemistry to purify chemical substances. The ... High-pressure liquid chromatography (HPLC) is a method used in chemistry and biochemistry to purify chemical substances. The ... High-pressure liquid chromatography (HPLC) is a method used in chemistry and biochemistry to purify chemical substances. The ... If an HPLC procedure is running at a pressure of 5.10×10^8 , what is its running pressure in torr? ...
Chromatography Research International is a peer-reviewed, Open Access journal that publishes original research and review ... A sensitive, specific, and rapid high-performance liquid chromatography-atmospheric pressure chemical ionization source-tandem ... Determination of Glucosamine in Human Plasma by High-Performance Liquid Chromatography-Atmospheric Pressure Chemical Ionization ... Chromatography Research International. Volume 2011, Article ID 815183, 7 pages. http://dx.doi.org/10.4061/2011/815183. Research ...
D. C. Turnell and J. D. H. Cooper, "Automated preparation of biological samples prior to high pressure liquid chromatography: ... Automated preparation of biological samples prior to high pressure liquid chromatography: Part I- The use of dialysis for ...
... Public Deposited ... Separations of Qams using ion-pair liquid chromatography were developed using reverse phase columns and both alkyl sulfonic ... acid and tetramethylammonium salts in the mobile phase as ion-pair liquid chromatography reagents. A continuous post-column ... Special apparatus for post-column solvent extraction of liquid chromatographic eluates was developed as part of this work. ...
... general Fluorides High performance liquid chromatography Mass spectrometry Resveratrol ... Rapid quantification of resveratrol in mouse plasma by ultra high pressure liquid chromatography (UPLC) coupled to tandem mass ... Ultra high pressure liquid chromatography Chromatographic separation was achieved by injecting 5 [micro]L of sample into a ... 21) to detect resveratrol in rat plasma by high pressure liquid chromatography (HPLC) has a run time of ,20 min and a LOQ of ...
... accurate and precise normal phase high pressure liquid chromatographic method was developed and validated for the simultaneous ... Fast gradient normal-phase high pressure liquid chromatography for rapid baseline separation of vitamin E forms in palm-derived ... Fast gradient normal-phase high pressure liquid chromatography for rapid baseline separation of vitamin E forms in palm-derived ... A rapid, accurate and precise normal phase high pressure liquid chromatographic method was developed and validated for the ...
High Pressure Liquid Chromatography System. Access many more Instruments and Laboratory Equipment Bids , Get your Free ...
SepPak C-18 purification preceded reverse phase high pressure liquid chromatography. High pressure liquid chromatography ... Angiotensin II in rat brain comigrates with authentic angiotensin II in high pressure liquid chromatography.. M I Phillips, B ... Angiotensin II in rat brain comigrates with authentic angiotensin II in high pressure liquid chromatography. ... Angiotensin II in rat brain comigrates with authentic angiotensin II in high pressure liquid chromatography. ...
This, together with the use of high-pressure liquid chromatography rather than gas chromatography for separating the sugar ... of glycoproteins and similar glycoconjugates by methanolysis followed by reverse-phase high-pressure liquid chromatography of ... High performance liquid chromatography High pressure liquid chromatography High price liquid chromatography Important ... Analysis of sugars in glycoproteins by high-pressure liquid chromatography.. @article{Jentoft1985AnalysisOS, title={Analysis of ...
MEASUREMENT OF PLASMA CHOLECYSTOKININS (CCKS) USING HIGH-PRESSURE LIQUID-CHROMATOGRAPHY (HPLC) AND RADIOIMMUNOASSAY (RIA) - ... MEASUREMENT OF PLASMA CHOLECYSTOKININS (CCKS) USING HIGH-PRESSURE LIQUID-CHROMATOGRAPHY (HPLC) AND RADIOIMMUNOASSAY (RIA) - ... MEASUREMENT OF PLASMA CHOLECYSTOKININS (CCKS) USING HIGH-PRESSURE LIQUID-CHROMATOGRAPHY (HPLC) AND RADIOIMMUNOASSAY (RIA) - ...
A method ... read more combining high-performance liquid chromatography coupled to positive ion atmospheric pressure chemical ... analysis of ladderane lipids in biomass and sediments using high performance liquid chromatography/atmospheric pressure ... analysis of ladderane lipids in biomass and sediments using high performance liquid chromatography/atmospheric pressure ... the ladderane lipids are difficult to analyze by gas chromatography. ...
Entry Terms : "High-Performance Liquid Chromatography (HPLC) Reagents" , "Chromatography Reagents, Liquid, High Pressure (HPLC ... Liquid, High-Pressure. Definition : Reagents intended for chromatography tests using a liquid phase forced by high pressure to ... High-Pressure Liquid Chromatography) Reagents" , "Homovanillic Acid (HVA) Determination Reagents" , "High-Pressure Liquid ... High-pressure liquid chromatography reagents are frequently used in the clinical laboratory to identify trace quantities of ...
Therefore, the authors developed a stereoselective high performance liquid chromatography-atmospheric pressure chemical ... The compounds were quantified in a single assay after liquid-liquid extraction and stereoselective high performance liquid ... Quantification of Methadone and a d6-labeled Isotopomer Using High Performance Liquid Chromatography-Atmospheric Pressure ... chromatograph with atmospheric pressure chemical ionization-mass spectrometry detection. The following ions were monitored: m/z ...
The extracts were examined with high-performance liquid chromatography-atmospheric pressure chemical ionization mass ... The extracts were examined with high-performance liquid chromatography-atmospheric pressure chemical ionization mass ...
Analytical Chemistry, Separation Sciences, Medicinal Chemistry, Bio Chemistry, Bio Analytical Chemistry, Water Chemistry, Separation Sciences, Green Chemistry, Inorganic Chemistry, Organic Chemistry, Forensic Chemistry, Industrial Chemistry, Gas chromatography, Pharmacology, and Pharmaceutical Sciences.
Fittings and tubing comprise a vital, but often ignored portion of the HPLC system. At first glance, the inexperienced eye sees little or no difference between fittings styles and brands. Although these components are not particularly complicated, a solid understanding of their application and use is essential to avoid certain HPLC problems.. ...
Chromatography Systems, Liquid, Packed Column, High-Pressure, Bonded-Phase. Definition : High-pressure packed-column liquid ... Home > Specialties > Chromatography Systems, Liquid, Packed Column, High-Pressure, Bonded-Phase. CLICK FOR ADVANCED SEARCH ... "Reverse-Phase Liquid Chromatography Systems" , "Normal-Phase Liquid Chromatography Systems" , "Bonded-Phase Liquid ... normal bonded-phase chromatography) or, more usually, nonpolar (i.e., reverse bonded-phase chromatography). ...
High Pressure Liquid Chromatography (HPLC)[edit]. HPLC systems are essentially based off of the same principles of thin-layer ... http://en.wikibooks.org/wiki/Structural_Biochemistry/Proteins/Purification/High_Pressure_Liquid_chromatography ... coupled with a high pressured eluent to force the sample through the column, HPLC obtains a higher degree of separation than ... Gas Chromatography[edit]. Gas chromatography using capillary columns are now one of the most commonly used methods in ...
... thin layer chromatography; TP53, tumor suppressor gene 53; UHPLC, ultra-high-pressure liquid chromatography. ... Ultra-High Pressure Liquid Chromatography (UHPLC). UHPLC (1290 Series, Agilent Technologies, Santa Clara, CA, USA) equipped ... Thin-Layer and High Performance Liquid Chromatography of Chinese Drugs; Springer: Heidelberg, Germany, 2011. [Google Scholar] ... Binds with high affinity to oncogene and cytokine RNA molecules. −0.432. GC35688. U04810. TROAP. Trophinin associated protein ( ...
In contrast, high-performance liquid chromatography (HPLC) relies on pressure to propel a fluid through a column. [0006] ... Patent application title: Liquid-Chromatography Conduit Assemblies Having High-Pressure Seals. Inventors: Waters Technologies ... High pressure fluidic switching valve having variable pressure loading. Top Inventors for class "Liquid purification or ... which includes at least one high-pressure seal and is a portion of a liquid chromatography-based apparatus, in accordance with ...
High Pressure Liquid Chromatography (HPLC). HPLC is used in courses at Shepherd including Instrumental Analysis. Dr. DiLella ... Liquid chromatography-mass spectrometry (LC/MS/MS). Waters 2680 Separations Module with autosampler, UV detector, and Micromass ... Gas chromatography-mass spectrometry (GC-MS). GC-MS is used in several courses at Shepherd including Organic Chemistry and ...
  • To overcome limitations of 2D gel electrophoresis, alternative techniques based on multidimensional liquid chromatography have been recently developed ( 1 , 2 ). (mcponline.org)
  • Automated two-dimensional liquid chromatography using the PF2D system from Beckman Coulter provides a fractionation platform well suited for differential proteomic studies. (openaire.eu)
  • Our results identify for the first time the storage locations of DMSP in microalgae, with high enrichments present in vacuoles, cytoplasm and chloroplasts. (elifesciences.org)
  • Antibacterial assay revels Lawsonia inermis showed highest zone of inhibition on Proteus sps. (ijper.org)
  • Spontaneously hypertensive rats did not have higher concentrations of hypothalamic angiotensin II than normotensive rats. (ahajournals.org)
  • Ibuprofen is one of the most consumed pharmaceuticals, measured in wastewater at very high concentrations and, despite its high removal rates, found in different environmental compartments. (environmental-expert.com)
  • Foscarnet concentrations were measured by high-pressure liquid chromatography. (nih.gov)
  • Inhibitors of cyclic electron transport interfered with desaturation only at rather high concentrations or not at all. (biomedsearch.com)
  • Method: BLG was enzymatically hydrolyzed by different proteases at an enzyme-to-substrate ratio of 1:100 under HHP (100 MPa) and compared with hydrolysates obtained under atmospheric pressure (AP-EH at 0.1 MPa). (mdpi.com)
  • Direct analysis in real time (DART) is an atmospheric pressure ion source that operates by exposing the sample to a gas stream (typically helium or nitrogen) that contains long-lived electronically or excited neutral atoms, vibronically excited molecules. (gre.ac.uk)
  • Objetivo: El objetivo del presente estudio consistia en desarrollar un metodo rapido y sensitivo para la cuantificacion de resveratrol, un compuesto de tipo polifenolico con multiples propiedades beneficiosas para la salud, en plasma de raton. (thefreelibrary.com)
  • El porciento de recuperation de resveratrol en plasma de raton fue de 85 [+ or -] 10% (promedio [+ or -] desviacion estandar). (thefreelibrary.com)
  • Conclusion: El metodo que hemos desarrollado permite la cuantificacion de resveratrol en plasma de raton de manera rapida y sensitiva. (thefreelibrary.com)
  • 12%, referred to the initial concentration of COC), and its concentration was slightly higher in preserved compared with unpreserved plasma at both storage temperatures chosen. (oup.com)
  • High cost of these instruments is the major factor restricting the market growth. (sbwire.com)
  • Conclusions: Enzymatic hydrolysis of BLG under HHP produces a higher yield of short bioactive peptides with potential antioxidant and anti-inflammatory effects. (mdpi.com)
  • Combined with high-efficiency ion trapping, this approach also provided significant improvements in sensitivity. (mcponline.org)
  • All the plants belonging to the F 1 's were analyzed by gas chromatography for cannabinoid composition and constantly found to have a mixed CBD-THC chemotype. (genetics.org)