Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The pressure due to the weight of fluid.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.
A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Chromatographic techniques in which the mobile phase is a liquid.
The rate dynamics in chemical or physical systems.
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
The sum of the weight of all the atoms in a molecule.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A syndrome related to increased atmospheric pressure and characterized by tremors, nausea, dizziness, decreased motor and mental performance, and SEIZURES. This condition may occur in those who dive deeply (c. 1000 ft) usually while breathing a mixture of oxygen and helium. The condition is associated with a neuroexcitatory effect of helium.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A plant genus of the LAMIACEAE family.
A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC
The pressure at any point in an atmosphere due solely to the weight of the atmospheric gases above the point concerned.
Enzymes catalyzing the oxidation of arachidonic acid to hydroperoxyarachidonates. These products are then rapidly converted by a peroxidase to hydroxyeicosatetraenoic acids. The positional specificity of the enzyme reaction varies from tissue to tissue. The final lipoxygenase pathway leads to the leukotrienes. EC 1.13.11.- .
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An enzyme of the oxidoreductase class primarily found in PLANTS. It catalyzes reactions between linoleate and other fatty acids and oxygen to form hydroperoxy-fatty acid derivatives.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
Eicosatetraenoic acids substituted in any position by one or more hydroxy groups. They are important intermediates in a series of biosynthetic processes leading from arachidonic acid to a number of biologically active compounds such as prostaglandins, thromboxanes, and leukotrienes.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Cyanogen bromide (CNBr). A compound used in molecular biology to digest some proteins and as a coupling reagent for phosphoroamidate or pyrophosphate internucleotide bonds in DNA duplexes.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.
Elements of limited time intervals, contributing to particular results or situations.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
The force per unit area that the air exerts on any surface in contact with it. Primarily used for articles pertaining to air pressure within a closed environment.
A group of LEUKOTRIENES; (LTC4; LTD4; and LTE4) that is the major mediator of BRONCHOCONSTRICTION; HYPERSENSITIVITY; and other allergic reactions. Earlier studies described a "slow-reacting substance of ANAPHYLAXIS" released from lung by cobra venom or after anaphylactic shock. The relationship between SRS-A leukotrienes was established by UV which showed the presence of the conjugated triene. (From Merck Index, 11th ed)
A biologically active tridecapeptide isolated from the hypothalamus. It has been shown to induce hypotension in the rat, to stimulate contraction of guinea pig ileum and rat uterus, and to cause relaxation of rat duodenum. There is also evidence that it acts as both a peripheral and a central nervous system neurotransmitter.
A lipoxygenase metabolite of ARACHIDONIC ACID. It is a highly selective ligand used to label mu-opioid receptors in both membranes and tissue sections. The 12-S-HETE analog has been reported to augment tumor cell metastatic potential through activation of protein kinase C. (J Pharmacol Exp Ther 1995; 274(3):1545-51; J Natl Cancer Inst 1994; 86(15):1145-51)
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.
The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.
The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Salts that melt below 100 C. Their low VOLATILIZATION can be an advantage over volatile organic solvents.
Techniques for measuring blood pressure.
Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
The process of cleaving a chemical compound by the addition of a molecule of water.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Proteins prepared by recombinant DNA technology.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Established cell cultures that have the potential to propagate indefinitely.
An emulsifying agent produced in the LIVER and secreted into the DUODENUM. Its composition includes BILE ACIDS AND SALTS; CHOLESTEROL; and ELECTROLYTES. It aids DIGESTION of fats in the duodenum.
A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.
Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.
Transducers that are activated by pressure changes, e.g., blood pressure.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Pressure within the cranial cavity. It is influenced by brain mass, the circulatory system, CSF dynamics, and skull rigidity.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The pressure of the fluids in the eye.
An essential amino acid. It is often added to animal feed.
Method in which repeated blood pressure readings are made while the patient undergoes normal daily activities. It allows quantitative analysis of the high blood pressure load over time, can help distinguish between types of HYPERTENSION, and can assess the effectiveness of antihypertensive therapy.
Materials in intermediate state between solid and liquid.
A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.
The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that are common in the marine environment and on the surfaces and in the intestinal contents of marine animals. Some species are bioluminescent and are found as symbionts in specialized luminous organs of fish.
A type of ion exchange chromatography using diethylaminoethyl cellulose (DEAE-CELLULOSE) as a positively charged resin. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Peptides composed of between two and twelve amino acids.
The blood pressure in the VEINS. It is usually measured to assess the filling PRESSURE to the HEART VENTRICLE.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.
Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The blood pressure in the ARTERIES. It is commonly measured with a SPHYGMOMANOMETER on the upper arm which represents the arterial pressure in the BRACHIAL ARTERY.
The pressure within a CARDIAC VENTRICLE. Ventricular pressure waveforms can be measured in the beating heart by catheterization or estimated using imaging techniques (e.g., DOPPLER ECHOCARDIOGRAPHY). The information is useful in evaluating the function of the MYOCARDIUM; CARDIAC VALVES; and PERICARDIUM, particularly with simultaneous measurement of other (e.g., aortic or atrial) pressures.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A chromatography technique in which the stationary phase is composed of a non-polar substance with a polar mobile phase, in contrast to normal-phase chromatography in which the stationary phase is a polar substance with a non-polar mobile phase.
The seventh planet in order from the sun. It is one of the five outer planets of the solar system. It has five known natural satellites.
A method of gel filtration chromatography using agarose, the non-ionic component of agar, for the separation of compounds with molecular weights up to several million.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Measurement of the pressure or tension of liquids or gases with a manometer.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
Procedures or techniques used to keep food from spoiling.
A modification of the freeze-drying method in which the ice within the frozen tissue is replaced by alcohol or other solvent at a very low temperature.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The eighth planet in order from the sun. It is one of the five outer planets of the solar system. Its two natural satellites are Nereid and Triton.
The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.
The blood pressure as recorded after wedging a CATHETER in a small PULMONARY ARTERY; believed to reflect the PRESSURE in the pulmonary CAPILLARIES.
Liquids transforming into solids by the removal of heat.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
A centrally acting muscle relaxant with a short duration of action.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
A rare metal element with a blue-gray appearance and atomic symbol Ge, atomic number 32, and atomic weight 72.63.
A CHROMATOGRAPHY method using supercritical fluid, usually carbon dioxide under very high pressure (around 73 atmospheres or 1070 psi at room temperature) as the mobile phase. Other solvents are sometimes added as modifiers. This is used both for analytical (SFC) and extraction (SFE) purposes.
The chemical and physical integrity of a pharmaceutical product.
The pressure required to prevent the passage of solvent through a semipermeable membrane that separates a pure solvent from a solution of the solvent and solute or that separates different concentrations of a solution. It is proportional to the osmolality of the solution.
Helium. A noble gas with the atomic symbol He, atomic number 2, and atomic weight 4.003. It is a colorless, odorless, tasteless gas that is not combustible and does not support combustion. It was first detected in the sun and is now obtained from natural gas. Medically it is used as a diluent for other gases, being especially useful with oxygen in the treatment of certain cases of respiratory obstruction, and as a vehicle for general anesthetics. (Dorland, 27th ed)
A series of steps taken in order to conduct research.
Devices for accelerating protons or electrons in closed orbits where the accelerating voltage and magnetic field strength varies (the accelerating voltage is held constant for electrons) in order to keep the orbit radius constant.
An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).
Quanta of acoustic energy which move at the speed of sound.
Measurement of the intensity and quality of fluorescence.
Period of contraction of the HEART, especially of the HEART VENTRICLES.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
Any aspect of the operations in the preparation, processing, transport, storage, packaging, wrapping, exposure for sale, service, or delivery of food.
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
The therapeutic intermittent administration of oxygen in a chamber at greater than sea-level atmospheric pressures (three atmospheres). It is considered effective treatment for air and gas embolisms, smoke inhalation, acute carbon monoxide poisoning, caisson disease, clostridial gangrene, etc. (From Segen, Dictionary of Modern Medicine, 1992). The list of treatment modalities includes stroke.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Creation and development of bodies within solar systems, includes study of early planetary geology.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The rhythmical expansion and contraction of an ARTERY produced by waves of pressure caused by the ejection of BLOOD from the left ventricle of the HEART as it contracts.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.
The branch of biology dealing with the effect of light on organisms.
A change of a substance from one form or state to another.
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
Inorganic compounds that contain calcium as an integral part of the molecule.
A ubiquitous sodium salt that is commonly used to season food.
A genus of zygomycetous fungi in the family Mucoraceae, order MUCORALES, forming mycelia having a metallic sheen. It has been used for research on phototropism.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.
Separation of a mixture in successive stages, each stage removing from the mixture some proportion of one of the substances, for example by differential solubility in water-solvent mixtures. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Organic and inorganic compounds that contain iron as an integral part of the molecule.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
Manometric pressure of the CEREBROSPINAL FLUID as measured by lumbar, cerebroventricular, or cisternal puncture. Within the cranial cavity it is called INTRACRANIAL PRESSURE.
The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.
A method of mechanical ventilation in which pressure is maintained to increase the volume of gas remaining in the lungs at the end of expiration, thus reducing the shunting of blood through the lungs and improving gas exchange.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
Methods of creating machines and devices.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
Proteins found in any species of bacterium.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

An Improved High Performance Liquid Chromatographic Method for Tryptophan Analysis in Rat Brain Administrated by Seaweed Abstract.
Indirect evidence has implicated a role for central angiotensin II in blood pressure control. To answer directly the question of whether angiotensin II exists in the brain, independent of blood-borne angiotensin, and to quantify the amounts in different parts of the central nervous system, a sensitive radioimmunoassay was used to measure extracts of male adult rat brain hypothalamus and cortex after purification with high pressure liquid chromatography with a high recovery. The fractions coeluted with authentic angiotensin. Rats were nephrectomized bilaterally, and 24 hours later the brains were extracted in acetic acid and boiled. SepPak C-18 purification preceded reverse phase high pressure liquid chromatography. High pressure liquid chromatography revealed two peaks, one which comigrated precisely with [Ile5] angiotensin II, and another smaller peak which overlapped with [Ile5] angiotensin III. The highest levels were found in the hypothalamus (125 pg/g tissue), pituitary (190 pg/g tissue), ...
TY - JOUR. T1 - Determination of transdermal sildenafil in nude mouse skin by reversed-phase high-performance liquid chromatography. AU - Liaw, Jiahorng. AU - Chang, Ting Wei. PY - 2001/12/25. Y1 - 2001/12/25. N2 - A simple and sensitive high-performance liquid chromatographic method was developed for the determination of sildenafil transdermal permeation of nude mouse skin. A reversed-phase column with UV detection at 224 nm was used for chromatographic separation. The mobile phase consisted of 32% acetonitrile with 0.2% phosphoric acid in water at pH 5.3 adjusted with 10 M NaOH with the flow-rate set at 1.0 ml/min. The limit of quantitation achieved was 5 ng/ml, and the calibration curve showed good linearity over the concentration range of 5-500 ng/ml. The relative standard deviations of within- and between-day analyses were all within 15%. Sildenafil was found to be stable between pH 3 and 12 during 24-h incubation with skin. After transdermal administration of 15.8 μg/ml of sildenafil to ...
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A new high-performance liquid chromatographic method was developed for quantification of midazolam in plasma samples from intensive care unit patients on long-term intravenous infusion of this benzodiazepine. Plasma samples (0.5 ml) were mixed with 1 microgram flurazepam (internal standard), alkalinized with 2.5 N NaOH, and extracted with toluene. The organic phase was evaporated to dryness, and the residue was dissolved in the mobile phase (acetonitrile/0.05 M phosphate buffer pH 4.5) and injected into the analytical column (C18 Nova-Pak 3.9 x 150 mm, 4 microns, maintained at room temperature; mobile phase flow rate: 1.2 ml/minute). The eluate was monitored at 207 nm, which reduced the risk of interferences from concurrent medications. Retention times of flurazepam, 1-hydroxymidazolam (an active metabolite) and midazolam were approximately 4.5, 6.1 and 13.5 minutes, respectively. The assay was linear over the range 100 to 3000 ng/ml. The coefficients of variation of the within-day and ...
A simple, sensitive and reproducible high-performance liquid chromatography (HPLC) method was developed for the determination of terazosin in human plasma. The method involves a one-step single solvent extraction procedure using dichloromethane with a 0.25 ml plasma sample. Recovery values were all greater than 90% over the concentration range 0.25-100 ng/ml. Terazosin was found to adsorb to glass or plastic tubes, but this could be circumvented by using disposable plastic tubes. Also, rinsing the injector port with methanol after each injection helped to prevent any carry-over effect. The internal standard, prazosin, did not exhibit this problem. The method has a quantification limit of 0.25 ng/ml. The within- and between-day coefficient of variation and accuracy values were all less than 7% over the concentration range 0.25-100 ng/ml and hence the method is suitable for use in pharmacokinetic studies of terazosin.
The 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.
A novel and generally applicable approach was established to hierarchically identify the bioactive components of a medicinal herb by preparative high-performance liquid chromatography (prep-HPLC) and a selective knock-out strategy. In this study, the targeted components of an herbal medicine were separated and knocked out using prep-HPLC. Subsequently, the contributions of the different target components to the overall effect of the medicinal herb were comparatively evaluated and differentiated by a heat map and a 3D score plot. This approach was successfully applied to investigate the bioactive constituents of safflower. The contributions of 11 components to the overall effect of safflower were as follows: anhydrosafflor yellow B(10)>6-hydroxykaempferol 3,6-di-O-beta-D-glucoside (8 > hydroxysafflor yellow A (3)> kaempferol 3-O-beta-rutinoside (11)> 6-hydroxykaempferol 3-O-beta-rutinoside (9)> 6-hydroxykaempferol 3,6-di-O-beta-D-glucoside-7-O-beta-D-glucuronide (4)> 6-hydroxyapigenin ...
An HPLC method for profiling 13 phytoestrogens and their metabolites using coulometric electrode array detection was developed. Sensitivity of the method was slightly less than that of our GC-MS method, but significantly higher compared to the HPLC methods using diode-array or UV detection. Detectio …
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 ...
GE AKTA fast protein liquid chromatography system is an eagle-i resource of type Fast protein liquid chromatography instrument at Universidad Central del Caribe.
The nearly 50% production capacity increase is in response to growing global demand for purification media from the antibody drug manufacturing industry.. At a cost of approximately ¥5 billion, the Nanyo Complexs Toyopearl production facilities are being expanded. Construction began in October 2016 and is slated for completion in August 2018. Commercial operations at the expanded production facilities are expected to commence in April 2019.. Liquid chromatography separation and purification media are used in the production of biopharmaceutical ingredients. Employing differences in charge, hydrophobicity, specific affinity, and molecular size, these media are designed to separate and purify target components. Given the rapid growth of the market for biopharmaceutical products, in Japan, the United States, and countries in Europe and in China, India, and other emerging nations, these media are in high demand. And Tosoh is committed to meeting that demand.. With its high strength, superior ...
China High Performance Liquid Chromatography, Spectrophotometer, HPLC (RAY-230 HPLC), Find details about China High Performance Liquid Chromatography, Spectrophotometer from High Performance Liquid Chromatography, Spectrophotometer, HPLC (RAY-230 HPLC) - Raylabel Instrument Co., Ltd.
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Background: Elevated circulating levels of BNP as detected on commercial antibody-based assays in heart failure (HF) patients may reflect a mixture of degraded BNP fragments, rather than intact BNP1-32.. Methods: Blood samples from 20 HF patients were collected, immediately centrifuged with plasma promptly aliquoted and frozen at -80°C. In a single thaw, 50uL of 10N HCL was added to 200 uL of plasma, incubated for 10 minutes then centrifuged. 100 uL of supernatant was injected into liquid chromatography mass spectrometry system. On-line extraction and high performance liquid chromatography methods were optimized using Onyx C18 guard and analytical column. Purified synthetic BNP1-32 was then incubated in patient serum and BNP fragments identified. Lastly, a proprietary protocol to inhibit BNP degradation was developed.. Results: The estimated limit of detection of the mass spectrometry method was 0.78 ng/mL and the lower limit of quantitation was 1.5 ng/mL with a good linear relationship ...
Biodistribution and metabolism of oligonucleotides were determined using a 3H-labeled 20-nucleotide phosphodiester and its phosphorothioate analog. The oligonucleotides were radiolabeled by 3H-methylation of an internal deoxyctidine with HhaI methylase and S- [3H]adenosylmethionine. Biodistribution studies were conducted after intravenous injection of 6 mg/kg (5 muCi) oligonucleotide. Metabolism of the oligonucleotides was determined by paired-ion high performance liquid chromatography. After phosphodiester injections, radiolabel rapidly cleared the blood. Relative initial concentrations were as follows: kidney , blood , heart , liver , lung , spleen. Radiolabel in spleen peaked at 1 hr and remained elevated for 24 hr. At 2 hr the concentration in all organs, except spleen, was equal to that in blood. High performance liquid chromatographic analysis of the kidney, liver, and spleen extracts and urine indicated extremely rapid metabolism to monomer. Results of studies after the injection of ...
A Simple, fast and precise reverse phase high performance liquid chromatographic method is developed for the simultaneous determination of Rosuvastatin Calcium and Fenofibrate. Chromatography was carried out at 400C and Separation of these drugs were performed on BDS C18 column (250 x 4.6 mm, 5 µ) as stationary phase with a mobile phase comprising of Acetonitrile: water (pH adjust to 2.5 with O-Phosphoric Acid) in the ratio of 70:30 (v/v) at a flow rate of 1.5 ml/min and Detection wavelength of Rosuvastatin Calcium and Fenofibrate ware 287nm. The Retention time for Rosuvastatin Calcium and Fenofibrate were 2min and 8.5min respectively. The linearity of Rosuvastatin Calcium and Fenofibrate was in the range of 1 to 5 µg/mL. The recovery was calculated by standard addition method. The proposed method was found to be accurate, precise and rapid for simultaneous determination of Rosuvastatin Calcium and Fenofibrate. It can be used for routine analysis.
TSKgel ODS-100V and TSKgel ODS-100Z columns incorporate the best-in-class surface properties to limit secondary interactions of basic, acidic and chelating compounds. Take advantage of the benefits of high column efficiency and symmetrical peak shapes to reduce your analysis and method development time! The ultra high purity Type B base silica contains negligible amounts of metal ion impurities. Combined with monomeric bonding chemistry, this silica makes the best general purpose Reversed Phase columns suitable for the most demanding separations in quality control as well as in research and development. TSKgel ODS-100V columns have a lower carbon content than ODS-100Z columns, making the bonded phase surface 100% water wettable and the preferred choice to retain polar metabolites.
Academic Journals Database is a universal index of periodical literature covering basic research from all fields of knowledge, and is particularly strong in medical research, humanities and social sciences. Full-text from most of the articles is available. Academic Journals Database contains complete bibliographic citations, precise indexing, and informative abstracts for papers from a wide range of periodicals.
SS Bioanalytics provides High pressure liquid chromatography development services, Its support in method development, method validations.
A simple and precise high performance liquid chromatography method for determination of candesartan cilexetil in their pharmaceutical formulation was developed and validated. The separation was carried out on Cosmosil C18 (250mm X 4.6, 5μ) RP-HPLC column using an 0.8ml/min as flow rate with methanol: water (80: 20 v/v) mobile phase. Quantification was performed with a UV detector at 214nm, solubility and stability was determined individually in simulated biological fluids at various pH was investigated. The calibration curves of candesartan cilexetil were linear in the range of 10-50 μg/ml (R²=0.999). The developed method was applied to pharmaceutical formulation successfully with no interfering peaks. The percentage recovery was 99.71-100.29%. It was observed that solubility of candesartan cilexetil was increased in all invitro medium, in 1.2 and slightly 7.4 pH and the stability of candesartan cilexetil was stable in pH 1.2 or degraded in pH 7.4 for 24 hours.
LiChrospher® HPLC Columns: LiChrospher® is a reliable and versatile traditionally produced spherical silica carrier with a particle size of 5µm or 10 µm, providing well balanced pressure / separation performance ratio. A broad range of modifications on LiChrospher® are very widely used by HPLC-users all over the world for a broad range of applications. LiChrospher® sorbents are available as reversed phase derivatives (RP-8, RP-18 endcapped, RP-18, RP-18 endcapped and RP-select B), medium polar (NH2, CN, DIOL) and polar derivatives (Si 60). Furthermore LiChrospher® PAH is highly efficient and selective for the separation of PAH; LiChrospher® WP is very well suited for the separation of peptides and low molecular weight proteins. LiChrospher® sorbents are available as Hibar® RT columns or as LiChroCART® cartridges in different lengths ans internal diameters. To operate with LiChroCART® cartridges, the cartridge holder manu-CART® has to be used.
MODEL RELEASED. (High pressure liquid chromatography) Biochemist analyses a new compound synthesized by microcide chemists for its interaction with biological macromolecules using HPLC. - Stock Image C009/4186
denaturing high performance liquid chromatography释义,背景概述,例举denaturing high performance liquid chromatography相关的SCI文献,让我们更理解denaturing high performance liquid chromatography的应用.
This paper reports the utilization of 2-pyrrolecarboxaldehyde-4-phenylsemicarbazone (PPS) as a complexing reagent for the simultaneous determination and separation of Ni(II), Cu(II), Pd(II), and Ag(I) by reversed-phase high-performance liquid chromatography with UV detector. A good separation was achieved using Microsorb C18 column (150 × 4.6 mm i.d.) with a mobile phase consisted of methanol : acetonitrile : water : sodium acetate (1 mM) (68 : 6.5 : 25 : 0.5 v/v/v/v) at a flow rate of 1 mL/min. The detection was performed at 280 nm. The linear calibration range was 2–10 |i|μ|/i|g/mL for all metal ions. The detection limits (S/N = 3) were 80 pg/mL for Ni(II), 0.8 ng/mL for Cu(II), 0.16 ng/mL for Pd(II), and 0.8 ng/mL for Ag(I). The applicability and the accuracy of the developed method were estimated by the analysis of Ni(II) in hydrogenated oil (ghee)
Fish oil made from menhaden (Brevoortia tyrannus) can be used as a dietary supplement for the presence of high levels of the long-chained omega-3 fatty acids, viz. epentaenoic and docosahexanoic. In this work, for the first time, two different multidimensional approaches were developed and compared, in terms of peak capacity, for triacylglycerol characterization. In particular, silver ion chromatography with a silver-ion column and non-aqueous reverse-phase liquid chromatography with a C18 column were tested in both comprehensive (stop-flow) and off-line modes. The use of mass spectra attained by atmospheric pressure chemical ionization for both LC approaches, and the fatty acids methyl esters profile of menhaden oil obtained by gas chromatography analysis, greatly supported the elucidation of the triacylglycerol content in menhaden oil. The off-line approach afforded a better separation and, thus, higher peak capacity to allow identifying and semiquantifying more than 250 triacylglycerols. Such a huge
Definition : High-pressure packed-column liquid chromatography systems in which the packing of the column is made of microparticulate silica gel. The functional groups of the stationary phase may be polar relative to those of the mobile phase (i.e., normal bonded-phase chromatography) or, more usually, nonpolar (i.e., reverse bonded-phase chromatography).. Entry Terms : Reverse-Phase Liquid Chromatography Systems , Normal-Phase Liquid Chromatography Systems , Bonded-Phase Liquid Chromatography Systems. UMDC code : 18278 ...
A unique polypeptide, called enhancing factor (EF), which enhances the binding of labeled epidermal growth factor (EGF) to cells, has been isolated. It has been purified to homogeneity from the acid-soluble proteins of mouse intestines. Earlier, EF was partially purified by two cycles of gel-permeation chromatography on Bio-Gel columns. We now report the final purification of EF on high-performance liquid chromatography (HPLC), using a reverse-phase column (μBondapak C18). The purity of the protein was confirmed when a single peak was obtained in HPLC. Also, a single protein band was obtained in SDS-PAGE. Purified EF has the same properties in vitro as those reported earlier for partially purified EF. ...
A simple and rapid extraction procedure was developed for determining aldehydes in rainwater samples. This extraction technique involved the use of micro-solid-phase extraction in which the sorbent was held within a polypropylene membrane envelope, followed by high-performance liquid chromatographic analysis. Aldehydes such as formaldehyde, acetaldehyde, propionaldehyde and valeraldehyde were used as model compounds. Extraction conditions were optimized. The method linearity ranged between 0.5 and 50μgl-1 with the correlation coefficient of 0.987-0.999. The relative standard deviations (RSDs) of the method ranged from 7 to 12%. Method detection limits were in the range of 0.07-0.15μgl-1, which is lower than those previously reported for solid-phase microextraction combined with gas chromatography-mass spectrometric techniques. The proposed extraction technique was used for determination of aldehydes in rainwater samples to demonstrate the applicability of the method. © 2010 Elsevier B.V ...
A simple and reliable reversed-phase high-performance liquid chromatographic (HPLC) method for the routine determination of vitamins A and E and β-carotene in plasma (or serum) with wavelength-programmed ultraviolet-visible absorbance detection is described. A 200-μl aliquot of serum or plasma sample, after deproteinization with ethanol, and containing tocopherol acetate as internal standard, was extracted with butanol-ethyl acetate. Sodium sulphate was added for dehydration. Analytes of extracted samples were found to be stable for at least four days. A 10-μl aliquot of this organic extract was used for HPLC analysis. The mobile phase was methanol-butanol-water (89.5:5:5.5, v/v) and the flow-rate was set at 1.5 ml/min. The analytes of interest were well separated from other plasma constituents within 22 min at 45°C. The lowest detection limits of vitamins A and E and β-carotene were 0.02, 0.5 and 0.1 μg/ml, respectively. The recovery and reproducibility of the present method were around ...
The 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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TY - JOUR. T1 - Hard modelling methods for the curve resolution of data from liquid chromatography with diode array detector and on-flow liquid chromatography with nuclear magnetic resonance spectroscopy. AU - Wasim, M. AU - Brereton, RG. N1 - Publisher: Amer. Chemical Soc. PY - 2006/4. Y1 - 2006/4. U2 - 10.1021/ci050112f. DO - 10.1021/ci050112f. M3 - Article (Academic Journal). VL - 46(3). SP - 1143. EP - 1153. JO - Journal of Chemical Information and Modeling. JF - Journal of Chemical Information and Modeling. SN - 1549-9596. ER - ...
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.
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[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 ...
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MATERIALS AND METHODS:. Chemicals and Reagents: Both Daunorubicin and Cytarabine (API) were obtained as a gift sample from Spectrum Pharma Pvt. Ltd., Hyderabad, India. The marketed formulation in the brand name Vyoxeos (Dauno-29 mg & Cyta-65 mg) procured from the local pharmacy. All the chemicals and reagents used in this work were HPLC grade water, acetonitrile, phosphate buffer, methanol, potassium dihydrogen orthophosphate buffer, orthophosphoric acid was obtained from Rankem.. Instrumentation: A HPLC system with waters 2695 separation module provided with a photodiode array detector, autosampler injection with Empower-2 software. Electronic balance, ultrasonicator, hot air oven were used.. Chromatographic Conditions: The chromatographic separations achieved on a kromosil C18 column (250 × 4.6 mm, 5 µm particle size) as a stationary phase. The mobile phase was composed of 55:45 v/v of 0.1% orthophosphoric acid (OPA) and acetonitrile at a flow rate of 0.8ml/min and injection volume is 10 ...
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 ...
For the isolation of the compound high pressure liquid chromatography is commonly used (HPLC). In the Fusarium species, ... It was also found that jungle bees in this area fly collectively in great numbers, at altitudes too high to be easily seen, ... This includes using activated charcoal, which has a high binding capacity of 0.48 mg of T-2 mycotoxin to 1 mg of charcoal. For ... Research has shown that a high dose of T-2 delays the ovulation due to a delayed follicle maturation. This possibly retards the ...
... and ultra-high pressure liquid chromatography. He has been an Lilly Analytical Research Fellow, Alfred P. Sloan Fellow, NSF ... Robert (Bob) Kennedy (born 1962) is an American chemist specializing in bioanalytical chemistry including liquid chromatography ... He is considered a leader in the field of analytical chemistry, and an expert in endocrinology, neurochemistry, and high- ... Martin Medal (2019) Ralph N. Adams Award in Bioanalyical Chemistry (2016) ACS Award in Chromatography (2017) CASSS Award for ...
It was fortunate indeed that, just around that time, the technique of high pressure liquid chromatography (HPLC) had been ... Huber, J. F. K. (1969). "High Efficiency, High Speed Liquid Chromatography in Columns". Journal of Chromatographic Science. 7 ( ... Using cadmium(II) as the coordinating metal ion led to a very high diastereoselectivity:44-46 in favor of the natural A/D-trans ...
More recently, the use of high-pressure liquid chromatography (HPLC) has become the preferred method, which allows for better ... Journal of Chromatography A. 8th International Symposium on High Performance Capillary Electrophoresis Part I. 744 (1-2): 167- ... Early methods to detect alpha-amanitin included thin-layer chromatography (TLC). In most solvent systems used in TLC, alpha- ... Also, amanitin-based antibody-drug conjugates using an anti-Her2 antibody such as trastuzumab showed high antitumor activity in ...
... high pressure liquid chromatography, and the formulation of the Rootare-Prenzlow Equation. In journalism, Edmund S. Valtman, a ... The pressures of industrialization drove numerous Estonian peasants to emigrate to the United States continuing until the ...
Chem., 62, 978-984 (1990). Ultra High Pressure Reversed Phase Liquid Chromatography in Packed Capillary Columns, J.E. MacNair, ... The group currently focuses on ultra-high pressure capillary liquid chromatography combined with mass spectrometry (MS). ... and the invention of ultra-high pressure liquid chromatography. His publications in separation methods have been extensively ... "Two-Dimensional High-Performance Liquid Chromatography/Capillary Electrophoresis", J.W. Jorgenson and M.M. Bushey, U.S. Patent ...
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 ...
... ultra-high pressure liquid chromatography) that operate at pump pressure a few-fold higher than HPLC instruments (see High- ... This is usually done by high-performance liquid chromatography (HPLC), but can also use the simpler technique of thin layer ... performance liquid chromatography#Pump pressure). Several factors effect the assay outcome and a recent review summarizes the ... "Improving Sensitivity in Liquid Chromatography-Mass Spectrometry". Journal of Chromatography B. 825 (2): 134-143. doi:10.1016/j ...
... chromatography, high pressure liquid MeSH E05.196.181.400.383 - chromatography, ion exchange MeSH E05.196.181.400.383.349 - ... chromatography, liquid MeSH E05.196.181.400.170 - chromatography, affinity MeSH E05.196.181.400.250 - chromatography, gel MeSH ... chromatography, deae-cellulose MeSH E05.196.181.400.454 - chromatography, paper MeSH E05.196.181.400.454.655 - nucleotide ... chromatography, thin layer MeSH E05.196.181.400.555 - countercurrent distribution MeSH E05.196.181.500 - chromatography, ...
... cerebrospinal fluid and/or urine using high-pressure liquid chromatography, with or without mass spectroscopy Genetic testing ... Homology models overlaid on each other show a high degree of overlap between the enzymes. The family of enzymes to which ADSL ...
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 a Bachelor of Arts in ...
... 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 ...
Umashankar D.C.; Chawla A.S.; Deepak M.; Singh D. & Handa S.S. (1999). "High pressure liquid chromatographic determination of ... and gallic acid from Bergenia ciliata and Bergenia ligulata by using thin-layer chromatography". Journal of Food Composition ... "High pressure liquid chromatographic determination of bergenin and (+) -afzelechin from different parts of Paashaanbhed ( ...
"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 work of Martin and Synge also set the stage for high performance liquid chromatography, suggesting that small sorbent ... particles and pressure could produce fast liquid chromatography techniques. This became widely practical by the late 1960s (and ... Martin, A J P; Synge, R L M (1941). "Separation of the higher monoamino-acids by counter-current liquid-liquid extraction: the ... Touchstone, Joseph C. (1993). "History of Chromatography". Journal of Liquid Chromatography. 16 (8): 1647-1665. doi:10.1080/ ...
... commonly coupled with high-performance liquid chromatography (HPLC). APCI is a soft ionization method similar to chemical ... "Atmospheric pressure ionization and liquid chromatography/mass spectrometry-together at last". Journal of the American Society ... "Recent developments in liquid chromatography-mass spectrometry and related techniques". Journal of Chromatography A. 1259: 3-15 ... Niessen, Wilfried (2006). Liquid Chromatography Mass spectrometry. 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL ...
"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 ...
... has found application as a rubber additive in the manufacture of high vinyl content rubber for high performance tires. DTHFP ... Ditetrahydrofurylpropane is a colorless liquid boiling at 145-146 °C at 60 mm Hg. It may be prepared by hydrogenation of 2,2-di ... In fact, the diastereomeric forms of DTHFP have been separated by column chromatography over silica gel. The symmetrical, meso ... Typical reaction times are a few hours at moderate temperatures at 100-800 psig hydrogen pressure. Ditetrahydrofurylpropane ( ...
For example, polymers can be separated by releasing the high pressure under which the scCO2 is held. This process is more ... Toners, instrument calibration standards, chromatography column packing materials, liquid crystal display spacers, and ... One dispersion polymerization system being studied is the use of supercritical liquid carbon dioxide (scCO2) as a solvent. ...
Present day liquid chromatography that generally utilizes very small packing particles and a relatively high pressure is ... Fast protein liquid chromatography. Fast protein liquid chromatography (FPLC), is a form of liquid chromatography that is often ... referred to as high-performance liquid chromatography (HPLC).. In HPLC the sample is forced by a liquid at high pressure (the ... paper chromatography, gas chromatography, and what would become known as high-performance liquid chromatography. Since then, ...
Concentration of tea is normally done through reduction of pressure. At high temperatures, the theaflavins in the solution are ... This process removes the high molecular weight compounds through ultrafiltration, absorption chromatography or oil filtration. ... For this reason, passing gas through the liquid provides a favorable condition for the compounds to leave the liquid. The ... By forcing the liquid extract through a nozzle, the solution atomizes, or becomes very fine droplets. These droplets are met ...
High performance liquid chromatography. Aqueous Normal Phase Chromatography. Size exclusion chromatography. Micellar liquid ... Incorporation of high temperature and pressure allows a significant increase in the efficiency of ion chromatography, along ... "The art and science of forming packed analytical high-performance liquid chromatography columns". Journal of Chromatography A. ... Svec, Frantisek.; Frechet, Jean M. J. (1992). "Continuous rods of macroporous polymer as high-performance liquid chromatography ...
The separated liquids are discharged without pressure and flow by gravity to exit the stage (note that exit is higher than ... Fig 6. Multi-stage process Radial chromatography G. Bernstein, et al., A high-capacity annular centrifugal contactor, Nuclear ... CINC Germany single and multi stage liquid liquid centrifugal extractors Centrifugal extractor for liquid liquid applications ... The separated liquids will be discharged without pressure. Fig 5. Separation direct feed Typically for solvent extraction ...
High-performance liquid chromatography (HPLC) is also sometimes referred to as high-pressure liquid chromatography. It is ... Thin layer chromatography[change , change source]. Main article: Thin layer chromatography. Thin layer chromatography (TLCC) is ... Column chromatography[change , change source]. Column chromatography separates compounds using many chemical actions between ... Double-way paper chromatography, also called 'two-dimensional chromatography', uses two solvents and rotates the paper 90° in ...
... provided it is sufficient to maintain a liquid state. This pressure is given by the saturated vapour pressure, and can be ... Smith, R. M.; Burgess, R.J. (1996). "Superheated water - a clean eluent for reverse phase high performance chromatography". ... and physical properties such as density start to change more significantly with pressure. However, higher pressures increase ... Superheated water is liquid water under pressure at temperatures between the usual boiling point, 100 °C (212 °F) and the ...
Laser spray is one of several ion sources that can be coupled with liquid chromatography-mass spectrometry for the detection of ... When a high voltage (3-4 kV) was applied to the stainless-steel capillary, strong ion signals appeared. The ion abundances were ... LSI's ability to ablate proteins at atmospheric pressure in order to form a multiple of charged ions with a mass resolution of ... Hiraoka, Kenzo; Saito, Shimpei; Katsuragawa, Jun; Kudaka, Ichiro (1998-09-15). "A new liquid chromatography/mass spectrometry ...
... utilizes ion exchange resins and is typically performed on fast protein liquid chromatography (FPLC) or ... A major drawback to this technique is that some proteins will aggregate when they are present at relatively high concentrations ... resulting in pressure buildup and possible equipment failure. Apparent aggregation issues can sometimes be overcome by limiting ... In contrast to typical ion exchange chromatography, where bound molecules are eluted from the resin by increasing the ionic ...
15 Test Method for Furanic Compounds in Electrical Insulating Liquids by High-Performance Liquid Chromatography (HPLC) D5839 - ... 20a Test Method for Vapor Pressure of Petroleum Products and Liquid Fuels (Mini Method-Atmospheric) D5483 - 20 Test Method for ... Antidegradants by High Performance Liquid Chromatography D5667 - 95(2019) Test Method for Rubber From Synthetic Sources-Total ... e1 Test Method for Analysis of Nitroaromatic and Nitramine Explosive in Soil by High Performance Liquid Chromatography D5144 - ...
... 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] ...
At high temperatures used to prepare glass, the material is a viscous liquid. The structure of glass forms into an amorphous ... It defines macroscopic variables, such as internal energy, entropy, and pressure, that partly describe a body of matter or ... chromatography, thermal analysis, electron microscope analysis, etc. Structure is studied at various levels, as detailed below ... Due to its higher electron mobility and saturation velocity compared to silicon, it is a material of choice for high-speed ...
... it occurs in a more ordered phase like liquid or solid as is the case with water (H2O); a liquid at room temperature because ... That is, substances with a higher Ka are more likely to donate hydrogen ions in chemical reactions than those with lower Ka ... For example, there are three phases of solid iron (alpha, gamma, and delta) that vary based on temperature and pressure. A ... They can be analyzed using the tools of chemical analysis, e.g. spectroscopy and chromatography. Scientists engaged in chemical ...
MDPV may be quantified in blood, plasma or urine by gas chromatography-mass spectrometry or liquid chromatography-mass ... High doses have been observed to cause intense, prolonged panic attacks in stimulant-intolerant users, and there are anecdotal ... in these patients can cause an unopposed peripheral alpha-adrenergic effect with a dangerous paradoxical rise in blood pressure ... by gas chromatography/mass spectrometry and liquid chromatography/quadrupole time-of-flight mass spectrometry". Rapid ...
The most common use of PETN is as an explosive with high brisance. It is more difficult to detonate than primary explosives, so ... PETN forms eutectic mixtures with some liquid or molten aromatic nitro compounds, e.g. trinitrotoluene (TNT) or tetryl. Due to ... The Los Angeles Times noted in November 2010 that PETN's low vapor pressure makes it difficult for bomb-sniffing dogs to detect ... in plasma using gas chromatography-mass spectrometry.[49] ... specifically in the high explosive Mine shell.[citation needed] ...
"Liquid chromatography-mass spectrometry: potential in forensic and clinical toxicology". Journal of Chromatography B. 733 (1-2 ... Lactotripeptides - Lactotripeptides might reduce blood pressure,[20][21][22] although the evidence is mixed.[23] ... These function, typically in higher organisms, as hormones and signaling molecules. Some organisms produce peptides as ... Xu JY, Qin LQ, Wang PY, Li W, Chang C; Qin; Wang; Li; Chang (October 2008). "Effect of milk tripeptides on blood pressure: a ...
As ytterbium(III) oxide has a significantly higher emissivity in the infrared range than magnesium oxide, a higher radiant ... although the exact transformation temperature depends on the pressure and stress.[7] The beta allotrope (6.966 g/cm3) exists at ... "Optimization of Separation of Ytterbium and Lutetium by Displacement Complexing Chromatography". Russian Journal of Applied ... ytterbium has the smallest liquid range of all the metals.[6] ... XIV: High Density-High Performance Decoy Flare Compositions ...
Emil Fischer Hermann Staudinger heterocyclic compound Hexane Hiddenite Hideki Shirakawa High performance liquid chromatography ... Valence Van der Waals radius Van der Waals force Vanadium Vapor pressure Vapour pressure Vermilion Victor Grignard Viktor Meyer ... of sound Sperrylite Spinel Spodumene stable isotope standard temperature and pressure Standard Ambient Temperature and Pressure ... p-block paint Palagonite Palladium Parabens Partial pressure Pascal (unit) Paul Berg Paul D. Boyer Paul J. Crutzen Paul J. ...
The reflectivity has advantages over silicon in neutron and high energy X-ray applications.[75] Crystals of high purity ... 3) were found to be less hazardous and may be used as a liquid substitute for toxic germane gas in semiconductor applications. ... At pressures above 120 kbar, it becomes the allotrope β-germanium with the same structure as β-tin.[28] Like silicon, gallium, ... Sol-Gel Hybrid Organic-Inorganic Coatings for Capillary Microextraction and Gas Chromatography". Anal. Chem. 79 (24): 9441-9451 ...
Extracts include liquid extracts, dry extracts, and nebulisates. Liquid extracts are liquids with a lower ethanol percentage ... For example, dangerously low blood pressure may result from the combination of an herbal remedy that lowers blood pressure ... Maceration is the cold infusion of plants with high mucilage-content, such as sage or thyme. To make macerates, plants are ... For this reason, thin layer chromatography is sometimes used by growers to assess the content of their products before use. ...
Low-pressure discharge. *Luminescent solar concentrator. *Lundquist number. *Luttinger liquid. MEdit. *Madison Symmetric Torus ... MARAUDER, acronym of Magnetically Accelerated Ring to Achieve Ultra-high Directed Energy and Radiation ... Chromatography detector. *Chromo-Weibel instability. *Classical-map hypernetted-chain method. *Cnoidal wave ...
The above reaction can be carried out by either of two methods: catalyzed gas-phase production or high pressure liquid-phase ... both based on liquid chromatography - mass spectrometry (LC/MS) detection after hydrophilic interaction liquid chromatography ( ... and high performance liquid chromatography. The result of the analysis showed that the calculus was composed of melamine and ... the FDA began using a high performance liquid chromatography test to determine the melamine, ammeline, ammelide, and cyanuric ...
High-efficient sorption, be used in desiccation, decarburization, desulphurization of gas and liquids and separation of ... Once the beads are full of water, temperature or pressure can be manipulated, allowing the water to be released from the ... Some molecular sieves are used in chromatography, a separation technique that sorts molecules based on their size. Other ... Sweetening (removal of thiols) of aviation fuel and corresponding liquid hydrocarbons 3Å[edit]. *Approximate chemical formula: ...
The compound is stable,[24] withstanding high temperatures and high pressures. The exposed surface of the structure can ... Talyzin, A.V. (1997). "Phase Transition C60−C60*4C6H6 in Liquid Benzene". Journal of Physical Chemistry B. 101 (47): 9679-9681 ... These fractions are separated using chromatography.[20] Generally, the fullerenes are dissolved in hydrocarbon or halogenated ... "high density, room temperature, ambient pressure storage of hydrogen". These OBBs are created by binding atoms of a transition ...
The gas is stored at high pressure.[45]. Argon-39, with a half-life of 269 years, has been used for a number of applications, ... Neutrino experiments include ICARUS and MicroBooNE, both of which use high-purity liquid argon in a time projection chamber for ... Argon may be used as the carrier gas in gas chromatography and in electrospray ionization mass spectrometry; it is the gas of ... Kleppe, Annette K.; Amboage, Mónica; Jephcoat, Andrew P. (2014). "New high-pressure van der Waals compound Kr(H2)4 discovered ...
Small high-pressure lamps can have light focused and transmitted to the work area via liquid-filled or fiber-optic light guides ... UVC LEDs are beginning to be used in disinfection[33] and as line sources to replace deuterium lamps in liquid chromatography ... or offset printing require high-intensity light focused via reflectors onto a moving substrate and medium so high-pressure Hg ( ... After 60 minutes, however, the amount of absorbed sunscreen was so high that the amount of ROS was higher in the sunscreen- ...
Covey TR, Lee ED, Henion JD (October 1986). "High-speed liquid chromatography/tandem mass spectrometry for the determination of ... Matz LM, Asbury GR, Hill HH (2002). "Two-dimensional separations with electrospray ionization ambient pressure high-resolution ... Similar to gas chromatography MS (GC-MS), liquid chromatography-mass spectrometry (LC/MS or LC-MS) separates compounds ... The duty cycle of IMS is short relative to liquid chromatography or gas chromatography separations and can thus be coupled to ...
... high pressure liquid chromatography, and the formulation of the Rootare-Prenzlow Equation. ... The pressures of industrialization drove numerous Estonian peasants to emigrate to the United States continuing until the ...
... the liquid to be filtered flows along the front of the membrane and is separated by the pressure difference between the front ... With high selectivity, isotopes can be enriched (uranium enrichment) in nuclear engineering or industrial gases like nitrogen ... another is measurement of the cut-off by gel permeation chromatography. These methods are used mainly to measure membranes for ... To determine the pore diameter, physical methods such as porosimetry (mercury, liquid-liquid porosimetry and Bubble Point Test ...
It also causes peripheral arterial disease and high blood pressure. The effects depend on the number of years that a person ... "Determination of aliphatic and aromatic aldehydes in cigarette smoke by gas chromatography with flame photometric detection". ... Smoking also increases blood pressure and weakens blood vessels.[72] Renal[edit]. In addition to increasing the risk of kidney ... A very large percentage of schizophrenics smoke tobacco as a form of self-medication.[125][126][127][128] The high rate of ...
Liquid chromatography may be used for liquid extractions of floral tissue. Detection and identificationEdit. Separation systems ... Floral scent emissions also vary along floral development, with highest emissions at anthesis,[19] i.e. when the flower is ... this phenotypic trait is subject to antagonistic selection pressures (positive selection by pollinators and negative selection ... Gas chromatography (GC) is ideal to separate volatilized VOCs due to their low molecular weight. VOCs are carried by a gas ...
This is why[citation needed] the arterioles have the highest pressure-drop. The pressure drop of the arterioles is the product ... Blood is a complex liquid. Blood is composed of plasma and formed elements. The plasma contains 91.5% water, 7% proteins and ... The ideal blood pressure in the brachial artery, where standard blood pressure cuffs measure pressure, is ,120/80 mmHg. Other ... with high flow rates that generate only small drops in pressure. The smaller arteries and arterioles have higher resistance, ...
If ion-exchange chromatography is used, the mixture of lanthanides is loaded into one column of cation-exchange resin and Cu2+ ... It is thus a mononuclidic element, and its standard atomic weight can be determined with high precision as it is a constant of ... following which sodium fluoride is removed from the reaction mixture with liquid hydrogen fluoride.[17] Additionally, ... Vapor pressure. P (Pa) 1 10 100 1 k 10 k 100 k ... As an alloying agent with magnesium to create high-strength ...
... others to high pressure, and a few, such as Deinococcus radiodurans, to high radiation environments. Microorganisms also make ... Scientists are researching the use of algae to produce liquid fuels,[93] and bacteria to convert various forms of agricultural ... "Production and Purification of Streptokinase by Protected Affinity Chromatography". Avicenna Journal of Medical Biotechnology ... Piezophiles thrive at very high pressures: up to 1,000-2,000 atm, down to 0 atm as in a vacuum of space.[80] A few ...
... is a yellowish coloured liquid component of blood that normally holds the blood cells in whole blood in suspension ... For example, when blood pressure drops in circulatory shock, Starling forces drive fluid into the interstitium, causing third ... and female donors who may have higher leukocyte antibodies.[13] However, some studies show an increased risk of TRALI despite ... Chromatography in blood processing. *Hypoxia preconditioned plasma. References[edit]. *^ Dennis O'Neil (1999). "Blood ...
12-18% low vapor pressure aliphatic hydrocarbon. Reduces the liquid's viscosity so that it can be used in aerosols. The ... In 2009, Wired published an article with the results of gas chromatography and mass spectroscopy tests on WD-40, showing that ... It warns of the product's high flammability and the risk of irritation to human skin when repeatedly exposed to WD-40. Nitrile ... creates pressure in the can to force the liquid through the can's nozzle before evaporating.[14] The product is also sold in ...
... high performance liquid chromatography, UV curing and printing, phototherapy, medical/ analytical instrumentation, and DNA ... Light pollution: Because white LEDs emit more short wavelength light than sources such as high-pressure sodium vapor lamps, the ... High-power LEDs (HP-LEDs) or high-output LEDs (HO-LEDs) can be driven at currents from hundreds of mA to more than an ampere, ... With the development of high-efficiency and high-power LEDs, it has become possible to use LEDs in lighting and illumination. ...
High Pressure Liquid Chromatography (HPLC). High Pressure Liquid Chromatography (HPLC). ... High Pressure Liquid Chromatography (HPLC) is an important separation technique for compounds of low or no volatility thus it ... The liquid mobile phase is the variable. Both the polarity and pH of the mobile phase can be varied. We possess a Waters 510 ...
... 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. 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" by people in this website by year, and whether "Chromatography, High Pressure Liquid" was a major or ... Chromatography, High Pressure Liquid*Chromatography, High Pressure Liquid. *Chromatography, Liquid, High Pressure ... Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed. ... "Chromatography, High Pressure Liquid" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, ...
Advantages of muramic acid measurement by high-pressure liquid chromatography are its high sensitivity and reduction of ... Muramic Acid Measurements for Bacterial Investigations in Marine Environments by High-Pressure Liquid Chromatography. Toru ... Muramic acid, a constituent of procaryotic cell walls, was assayed by high-pressure liquid chromatography in samples from ... Muramic Acid Measurements for Bacterial Investigations in Marine Environments by High-Pressure Liquid Chromatography ...
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. ...
Ion-exclusion high-pressure liquid chromatography (HPLC) was used to measure poly-β-hydroxybutyrate (PHB) in Rhizobium ... Analysis of Poly-β-Hydroxybutyrate in Rhizobium japonicum Bacteroids by Ion-Exclusion High-Pressure Liquid Chromatography and ... Analysis of Poly-β-Hydroxybutyrate in Rhizobium japonicum Bacteroids by Ion-Exclusion High-Pressure Liquid Chromatography and ... Analysis of Poly-β-Hydroxybutyrate in Rhizobium japonicum Bacteroids by Ion-Exclusion High-Pressure Liquid Chromatography and ...
Here we present an original and rapid approach using ultra-high pressure liquid chromatography-atmospheric pressure chemical ... Conventional methods are based on liquid chromatography coupled to ultraviolet and fluorescence detection of a single or ... Prenylquinone levels were measured in leaves of ,i,Arabidopsis,/i, grown under normal and high light intensities. ... Mass spectrometry and chromatography parameters were optimized using pure standards. Sample preparation time was kept to ...
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 ...
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 ...
High pressure liquid chromatography quantification. Quantification of intracellular ATP was carried out using high pressure ... High expression of FER tyrosine kinase predicts poor prognosis in clear cell renal cell carcinoma. Oncol. Lett. 5, 473-478 ( ... liquid chromatography (HPLC) as previously described7.. Measurement of the mitochondrial OXPHOS complex I activity. Activity of ... Interestingly, the high-grade metastatic CC and pancreatic cancer cells were more sensitive to E260 than low grade CC and ...
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.
SS Bioanalytics provides High pressure liquid chromatography development services, Its support in method development, method ...
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.. ...
High Performance Liquid Chromatography,High Pressure Liquid Chromatography,HILIC,HPLC,HPLC Column,Liquid Chromatography,Liquid ... High Performance Liquid Chromatography,High Pressure Liquid Chromatography,lc-ms,LC/MS Sensitivity,LC/MS/MS,liquid liquid ... High Performance Liquid Chromatography,High Pressure Liquid Chromatography,LC vials,Liquid Chromatography,Sample Preparation, ... High Performance Liquid Chromatography,High Pressure Liquid Chromatography,High-Performance Gradient Elution,Liquid ...
Shock and pulse damping in the liquid foods, dugs, and beverage industries. Dampner viewsheet: high pressure liquid ... Pulsation dampers for flow and pressure by PulseGuard. ... See Also: Pulsation Dampers - High Pressure Liquid ... When the liquid is bio chemical, this could be the awnser. Eight sizes, several pressures, CB and triclover or international ...
Terms and Conditions , Privacy Statement , Trademarks , Cookie Usage © Copyright 2020 Thermo Fisher Scientific Inc. All rights reserved. ...
High Pressure Liquid Chromatography (HPLC). The annealed amorphous atorvastatin calcium was analyzed for impurities and ... The invention is also directed to a process for annealing amorphous atorvastatin at elevated or high pressure. According to the ... A process for annealing amorphous atorvastatin at elevated or high pressure comprising treating amorphous atorvastatin at a ... A process of claim 10, wherein said pressure is cycled between about ambient pressure and about 200 kBars two or more times. 16 ...
  • The highest voltage of SYS LC 138 can be reached to 10000 psi, and the minimum detection limit is 1×10-9g/ml. (
  • Instead of introducing the solvent into the column and allowing it to drip down under the influence of gravity, in HPLC the sample is forced through the column under high pressures of nearly 400 atm, resulting in faster and more efficient separation. (
  • 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. (
  • The SYS LC 138 Liquid Chromatograph System adopts the most advanced liquid chromatography system called VI2010 HPLC Data Work Station, which designed for international standard, all the action of SYS LC 138 can be directly controlled by the computer. (
  • Improved high-performance liquid chromatographic analysis of terazosin in human plasma. (
  • A simple, sensitive and reproducible high-performance liquid chromatography (HPLC) method was developed for the determination of terazosin in human plasma. (
  • High performance liquid chromatography (HPLC) has become a very versatile and powerful separation and analytical method over the years. (
  • Retrieved on October 27, 2020 from (
  • It is usually a blend of polar and non-polar liquids whose concentrations depend on the sample composition. (
  • The sample is injected into the column by an injector which is capable of handling sample volumes in the range of 0.1 - 100mL under high pressures of up to 4000psi. (
  • Lu H, Yu J, Wu L, Xing J, Wang J, Huang P, Zhang J, Xiao H, Gao R. Optimized ultra performance liquid chromatography tandem high resolution mass spectrometry method for the quantification of paraquat in plasma and urine. (
  • Lu H, Yu J, Wang J, Wu L, Xiao H, Gao R. Simultaneous quantification of neuroactive dopamine serotonin and kynurenine pathway metabolites in gender-specific youth urine by ultra performance liquid chromatography tandem high resolution mass spectrometry. (
  • A rapid, sensitive and widely applicable method for quantitative analysis of underivatized amino acids in different biological matrices by ultra-performance liquid chromatography-tandem mass spectrometry. (
  • Urinary levels of 2-thiothiazolidine-4-carboxylic acid (a marker of carbon disulfide and vulcanization fumes) were assessed by liquid chromatography coupled with mass spectrometry. (
  • A sensitive, specific, and rapid high-performance liquid chromatography-atmospheric pressure chemical ionization source-tandem mass spectrometry (HPLC-APCI-MS/MS) method for the determination of glucosamine in human plasma was developed and validated. (
  • Methods: We used reversed-phase ultra high pressure liquid chromatography with tandem mass spectrometry detection for the determination of resveratrol levels in mouse plasma. (
  • Metodos: Utilizamos cromatografia liquida con presion ultra alta acoplada a espectrometria de masa en serie, para la determination de los niveles de resveratrol en plasma de raton. (
  • A rapid, accurate and precise normal phase high pressure liquid chromatographic method was developed and validated for the simultaneous determination of nine vitamin E forms comprised of α-tocomonoenol, α-, β-, γ-, and δ-tocopherols and α-, β-, γ-, and δ-tocotrienols in tocotrienol rich fractions (TRFs) derived from palm oil. (
  • A method for the determination of cocaine (COC), benzoylecgonine (BE), ecgonine methyl ester (EME), and ecgonine (ECG) in plasma by liquid chromatography-mass spectrometry (LC-MS-MS) was developed. (
  • A new and simple method for the determination of rat liver microsomal uridine diphosphate glucuronosyltransferase activity toward 4-nitrophenol, phenolphthalein, and testosterone has been developed with the use of high-pressure liquid chromatography (hplc). (
  • A Comparison of Three Different High Pressure Liquid Chromatography Systems for the Determination of Aldehydes and Ketones in Diesel Exhaust," Journal of Chromatographic Science , Oxford University Press, Jan 1982. (
  • Hordijk, CA & Cappenberg, TE 1983, ' Quantitative High-Pressure Liquid Chromatography-Fluorescence Determination of Some Important Lower Fatty Acids in Lake Sediments ', Applied and Environmental Microbiology , vol. 46, no. 2, pp. 361-369. (
  • In the present study, we developed and validated a method that uses liquid extraction coupled with HPLC-MS/MS determination to measure TCC in feces. (
  • An accurate, simple, and sensitive method for the direct determination of proteins by nonspecies specific isotope dilution and external calibration high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS) is described. (
  • Effect of difluoroacetic acid and biological matrices on the development of a liquid chromatography - triple quadrupole mass spectrometry method for determination of intact growth factor proteins. (
  • High Pressure Liquid Chromatography (HPLC) is an important separation technique for compounds of low or no volatility thus it makes a nice complimentary procedure to GC. (
  • The Bruker Maxis 4G ETD Ion Mobility (incl UPLC) combines high resolution/accurate mass with separation based on molecular shape (by Ion Mobility). (
  • The separation was achieved by high pressure liquid chromatography on a Vydac pellicular anion exchange column using a linear gradient of 0.5 to 1.0 m acetic acid as the eluting solvent. (
  • To ensure high separation efficiency, low gradient response times and superior mixing performance we offer perfectly matched HPLC and UHPLC system components. (
  • Skalnikova, H., Halada, P., Dzubak, P., Hajduch, M. and Kovarova, H. (2005) Protein fingerprints of anti-cancer effects of cyclin-dependent kinase inhibition: 320 identification of candidate biomarkers using 2-d liquid phase separation coupled to mass spectrometry. (
  • Liquid chromatography separation of α- and γ-linolenic acid positional isomers with a stationary phase based on covalently immobilized cellulose tris(3,5-dichlorophenylcarbamate). (
  • Achieve up to four times throughput on your single triple quadrupole or high resolution mass spectrometer using the multi-channel turbulent flow liquid chromatography system. (
  • High-pressure liquid chromatography (HPLC) is a method used in chemistry and biochemistry to purify chemical substances. (
  • D. C. Turnell and J. D. H. Cooper, "Automated preparation of biological samples prior to high pressure liquid chromatography: Part I- The use of dialysis for deproteinizing serum for amino-acid analysis," Journal of Automatic Chemistry , vol. 7, no. 4, pp. 177-180, 1985. (
  • Turbulent flow liquid chromatography was developed in the late 1990s, and combines 'size exclusion' and traditional stationary phase column chemistry to separate macromolecules, such as proteins, from smaller molecules and analytes of interest in biological fluids. (
  • High pressure liquid chromatography (HPLC) is typically used to separate a mixture of compounds in analytical chemistry and biochemistry with the purpose of identifying, quantifying or purifying the individual components of the mixture. (
  • Robert (Bob) Kennedy (born 1962) is an American chemist specializing in bioanalytical chemistry including liquid chromatography, capillary electrophoresis, and microfluidics. (
  • He is considered a leader in the field of analytical chemistry, and an expert in endocrinology, neurochemistry, and high-throughput analysis. (
  • Major contributions to analytical chemistry include affinity probe capillary electrophoresis, in vivo neurochemical measurements, and ultra-high pressure liquid chromatography. (
  • Baclofen was identified in urine by gas chromatography/mass spectrometry. (
  • After derivatization with trinitrobenzene sulfonic acid, baclofen was quantitated in serum and urine by high-performance liquid chromatography. (
  • Special apparatus for post-column solvent extraction of liquid chromatographic eluates was developed as part of this work. (
  • Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed. (
  • 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. (
  • Our products are used in analytical laboratories worldwide, where they are known for quality, ease of use and high level of support. (
  • Waters Corporation has been in the business of making innovative analytical instruments that assist scientists in reaching their scientific goals, increase productivity, and earn laboratory-based organizations a higher return on their investments in research, development, and quality control. (
  • For high-resolution and high-sensitivity separations that are ideally suited for use with mass spectrometry and designed for laboratories with less throughput or where sample preparation is done as a separate step in their analytical workflow. (
  • Advantages of muramic acid measurement by high-pressure liquid chromatography are its high sensitivity and reduction of preparation steps, allowing a short time analysis. (
  • Accurate mass measurements to determine elemental composition, high sensitivity MS and MS/MS measurements. (
  • Ultra high pressure liquid chromatography (UHPLC) typically using 1.7 micron column particle size provides significantly more resolution (information) while reducing run times, and improves sensitivity for the analyses of many compound types. (
  • Combined with high-efficiency ion trapping, this approach also provided significant improvements in sensitivity. (
  • We found that automated 2D chromatography improved the sensitivity and accuracy of both PRM and an intact precursor scanning mass spectrometry method, termed accumulated ion monitoring (AIM), by more than 100-fold. (
  • High pressure liquid chromatography) Biochemist analyses a new compound synthesized by microcide chemists for its interaction with biological macromolecules using HPLC. (
  • Quantitative proteomics using high-resolution and accuracy mass spectrometry promises to transform our understanding of biological systems and disease. (
  • The combination of automated multidimensional nano-scale chromatography and targeted mass spectrometry should enable ultrasensitive high-accuracy quantitative proteomics of complex biological systems and diseases. (
  • Invasive species can quickly transform biological communities due to their high abundance and strong impacts on native species, in part because they can be released from the ecological forces that limit native populations. (
  • In the current study, an innovative combination of high hydrostatic pressure and enzymatic hydrolysis (HHP-EH) was used to increase the yield of short bioactive peptides, and evaluate the anti-inflammatory and antioxidant properties of the BLGH produced by the HHP-EH process. (
  • The BLGH produced by alcalase (Alc) (BLG-Alc) showed significantly higher antioxidant properties among the six enzymes examined in this study. (
  • 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. (
  • Park, K.H., Lipuma, J.J. and Lubman, D.M. (2007) Comparative proteomic analysis of b. cenocepacia using two-dimensional liquid separations coupled with 340 mass spectrometry. (
  • To enable sensitive and specific targeted mass spectrometry, we implemented an automated, two-dimensional (2D) ion exchange-reversed phase nanoscale chromatography system. (
  • We extracted protein isoforms from polyacrylamide gels by passive elution using SDS, followed by nanoscale hydrophilic phase chromatography for SDS removal. (
  • To overcome limitations of 2D gel electrophoresis, alternative techniques based on multidimensional liquid chromatography have been recently developed ( 1 , 2 ). (
  • The liquid mobile phase is the variable. (
  • 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. (
  • In this study, we use the state-of-the-art, ultracentrifugation-electrostatic repulsion hydrophilic interaction chromatography (UC-ERLIC)-coupled mass spectrometry technology to undertake a comparative characterization of uDPMs in the soluble and particulate postmortem brain fractions of subjects diagnosed with AD + CVD and age-matched controls. (
  • Therefore, the authors developed a stereoselective high performance liquid chromatography-atmospheric pressure chemical ionization mass-spectrometry assay for the quantification of the enantiomers of methadone and a d6-labeled isotopomer. (
  • To overcome these limitations, parallel reaction monitoring (PRM) has been developed by leveraging high-resolution Orbitrap mass analyzers to improve assay specificity because of monitoring fragment ions with parts per million (ppm) mass accuracy ( 13 , 14 ). (
  • Antibacterial assay revels Lawsonia inermis showed highest zone of inhibition on Proteus sps. (
  • 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. (
  • SepPak C-18 purification preceded reverse phase high pressure liquid chromatography. (
  • Sample preparation time was kept to minimum and different extraction solvents were evaluated for yield, ability to maintain the redox state of prenylquinones, and compatibility with chromatography. (
  • We offer access to a range of equipment, including a variety of complementary chromatography techniques, ionisation sources and extraction methods. (
  • Lamivudine was isolated by liquid-liquid and solid phase extraction. (
  • High reproducibility of two-dimensional liquid chromatography using pH-driven fractionation with a pressure-resistant electrode. (
  • Chromatography, High Pressure Liquid" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (
  • Automated two-dimensional liquid chromatography using the PF2D system from Beckman Coulter provides a fractionation platform well suited for differential proteomic studies. (
  • A method for making a liquid-chromatography apparatus includes inserting two inner conduits into an intermediate tube, inserting the intermediate tube into an outer tube, forming a proximal seal between the intermediate tube and at least one of the inner conduits, and forming a distal seal between the intermediate tube and at least one of the inner conduits. (
  • 24. The apparatus of claim 22, further comprising a fluidic interface disposed at the interface between the liner tube and the optical conduit to provide a fluid passageway in communication with the liquid in the liner tube. (
  • [0002] The invention generally relates to chromatography apparatus that operate at high pressure. (
  • High serum serotonin in sudden infant death syndrome. (
  • Conventional methods are based on liquid chromatography coupled to ultraviolet and fluorescence. (
  • Likewise, the incorporation of high-resolution time-of-flight (TOF) mass analyzers has been used to improve the accuracy of reaction monitoring methods, including their use in data-independent approaches such as SWATH ( 15 , 16 ). (
  • 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. (
  • When the liquid is bio chemical, this could be the awnser. (
  • Chromatography is a way of separating two or more chemical compounds. (
  • For clinical translational research, most laboratories seek high performance systems to meet their demanding needs in addition to support the connection to their mass spectrometer. (
  • With TurboFlow™ Technology, dramatically increase the return on your capital investment in mass spectrometer technology by improving data quality, lowering per-sample costs and increasing sample throughput using automated online sample preparation and multichannel liquid chromatography multiplexing. (
  • Gas chromatography mass spectrometry (GC-MS) is an instrumental technique, comprising a gas chromatograph (GC) coupled to a mass spectrometer (MS), by which complex mixtures of chemicals may be separated, identified and quantified. (
  • In addition to precise absolute quantification of 5 prenyllipids for which standards were available, relative quantification of 6 other related compounds was possible thanks to the high identification power of QTOFMS. (
  • ES Industries offers the HPLC chromatographer an important source for high performance bonded phases and packing materials. (
  • Selection by the Scholarship Committee will be based upon the applicant's academic performance in high school, leadership, extracurricular involvement and community service. (
  • Due to the thermal lability of the strained cyclobutane moieties, the ladderane lipids are difficult to analyze by gas chromatography. (
  • 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. (
  • El porciento de recuperation de resveratrol en plasma de raton fue de 85 [+ or -] 10% (promedio [+ or -] desviacion estandar). (
  • Conclusion: El metodo que hemos desarrollado permite la cuantificacion de resveratrol en plasma de raton de manera rapida y sensitiva. (
  • 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. (
  • Molecular sieving using Sephadex G-25 with acetic acid revealed a distinct peak in the 1000 MW range and a smaller, higher molecular weight peak which needs further investigation. (
  • To our knowledge, these are the highest numbers of molecular compositions of O2NAs that have been profiled thus far in environmental samples. (
  • It was also found that jungle bees in this area fly collectively in great numbers, at altitudes too high to be easily seen, producing showers of feces that could have been mistaken for sprays from aircraft. (
  • 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. (
  • In combination with the high-resolution imaging techniques described here, this will allow researchers to fully understand the role that DMSP plays in these organisms. (
  • A Basic Rundown of Supercritical Fluid Chromatography By: Christina Dyczewski, Executive Account Manager Over the last several years, there has been an increased interest in SFC (Supercritical Fluid Chromatography). (
  • 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. (