Water Movements
Chromatography, High Pressure Liquid
Chromatography
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
Water Pollutants
Chromatography, Thin Layer
Chromatography, Reverse-Phase
Porosity
Solubility
Mass Spectrometry
Spectrometry, Mass, Electrospray Ionization
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
Amino Acid Sequence
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Chromatography, Gas
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Chromatography, Affinity
Chromatography, Gel
Chromatography, Ion Exchange
Lipid Bilayers
Temperature
Chemistry, Physical
Physicochemical Phenomena
Phosphatidylcholines
Water
Membrane Fluidity
1,2-Dipalmitoylphosphatidylcholine
Rheiformes
Membrane Lipids
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
Solutions
Apatites
Models, Chemical
Air
X-Ray Diffraction
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Thermodynamics
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
Hydrogen-Ion Concentration
Solvents
Cattle
Polyethylene Glycols
Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.
Membranes, Artificial
Phospholipids
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Cholesterol
Electrophoresis, Polyacrylamide Gel
Chemical Fractionation
Surface Properties
Hydroxyapatites
A group of compounds with the general formula M10(PO4)6(OH)2, where M is barium, strontium, or calcium. The compounds are the principal mineral in phosphorite deposits, biological tissue, human bones, and teeth. They are also used as an anticaking agent and polymer catalysts. (Grant & Hackh's Chemical Dictionary, 5th ed)
Volatilization
Chromatography, DEAE-Cellulose
Polymers
Calorimetry, Differential Scanning
Detergents
Membrane Microdomains
Physical Phenomena
Diffusion
Cell Membrane
Ionic Liquids
Calcium Phosphates
Countercurrent Distribution
Dimyristoylphosphatidylcholine
Complex Mixtures
Pressure
Gas Chromatography-Mass Spectrometry
Liposomes
Chromatography, Agarose
Hydrophobic and Hydrophilic Interactions
Gels
Sphingomyelins
Materials Testing
Phosphatidylethanolamines
Benzyl Alcohol
Glycols
Surface-Active Agents
Tandem Mass Spectrometry
A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
Magnetic Resonance Spectroscopy
beta-Keratins
Amino Acids
Physics
Succinic Acid
A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851)
Spectrophotometry, Ultraviolet
Diphenylhexatriene
Escherichia coli
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Macromolecular Substances
Chromatography, Paper
Crystallization
Models, Biological
Nanostructures
Molecular Structure
Protein Binding
Chemistry
Peptides
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Silicon Dioxide
Chemical Phenomena
Substrate Specificity
Freeze Fracturing
Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.
Lipids
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Proteins
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
Cell Fractionation
Membrane Proteins
Reproducibility of Results
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Colloids
Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.
Chromatography, Micellar Electrokinetic Capillary
Microscopy, Electron, Scanning
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
Microscopy, Atomic Force
A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.
Structure-Activity Relationship
Computer Simulation
Isoelectric Focusing
Fluorescent Dyes
Indicators and Reagents
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
Fatty Acids
Emulsions
Colloids formed by the combination of two immiscible liquids such as oil and water. Lipid-in-water emulsions are usually liquid, like milk or lotion. Water-in-lipid emulsions tend to be creams. The formation of emulsions may be aided by amphiphatic molecules that surround one component of the system to form MICELLES.
Phosphatidylglycerols
Thymolphthalein
Swine
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Calibration
Hemoglobin C
Carbohydrates
Models, Molecular
Crystallins
A heterogeneous family of water-soluble structural proteins found in cells of the vertebrate lens. The presence of these proteins accounts for the transparency of the lens. The family is composed of four major groups, alpha, beta, gamma, and delta, and several minor groups, which are classed on the basis of size, charge, immunological properties, and vertebrate source. Alpha, beta, and delta crystallins occur in avian and reptilian lenses, while alpha, beta, and gamma crystallins occur in all other lenses.
Scattering, Radiation
Reference Standards
Liver
Dextrans
Rabbits
Anxiety, Separation
Peptide Fragments
Base Sequence
Microscopy, Fluorescence
Chemistry, Pharmaceutical
Microchemistry
Stereoisomerism
Calorimetry
The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Electrophoresis, Capillary
Limit of Detection
Isoelectric Point
Microscopy, Electron
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Carbohydrate Sequence
Biocompatible Materials
Serum Albumin, Bovine
Trypsin
Biopolymers
Lens, Crystalline
Binding Sites
Oligosaccharides
Erythrocyte Membrane
Microspheres
Fluorescence Polarization
Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.
Protein Conformation
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Phosphatidylserines
Chemistry Techniques, Analytical
Sensitivity and Specificity
Spin Labels
Deuterium
Immunomagnetic Separation
A cell-separation technique where magnetizable microspheres or beads are first coated with monoclonal antibody, allowed to search and bind to target cells, and are then selectively removed when passed through a magnetic field. Among other applications, the technique is commonly used to remove tumor cells from the marrow (BONE MARROW PURGING) of patients who are to undergo autologous bone marrow transplantation.
Transition Temperature
Electrophoresis
Species Specificity
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Solid Phase Extraction
Methanol
1-Octanol
Isomerism
Spectroscopy, Fourier Transform Infrared
Compressive Strength
Electron Spin Resonance Spectroscopy
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
Centrifugation, Density Gradient
Models, Theoretical
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
Radioimmunoassay
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
Plant Extracts
Glycoproteins
Polyesters
Immunodiffusion
Cloning, Molecular
Ceramides
Nanofibers
Spectrophotometry
Electrochemistry
Adsorption
DNA
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Liquid chromatography-mass spectrometry
... is a method of physical separation in which the components of a liquid mixture are distributed between two immiscible phases, i ... Among these, the most widely used variant is the reverse-phase (RP) mode of the partition chromatography technique, which makes ... TSP was also more suitable for LC-MS applications involving reversed phase liquid chromatography (RT-LC). With time, the ... James, A. T.; Martin, A. J. P. (1952-03-01). "Gas-liquid partition chromatography: the separation and micro-estimation of ...
Partition chromatography
In liquid-liquid separation, a compound is distributed between two immiscible liquid phases under equilibrium conditions. ... "Liquid Chromatography with Hydrocarbonaceous Bonded Phases; Theory and Practice of Reversed Phase Chromatography". Journal of ... separation process whereby compounds were partitioned between two liquid phases similar to the separatory funnel liquid-liquid ... James, A. T.; Martin, A. J. P.; Smith, G. Howard (1 October 1952). "Gas-liquid partition chromatography: the separation and ...
Countercurrent chromatography
... both the mobile and stationary phases are liquid. The contrast is, however, not as stark as it first appears. In reversed-phase ... The analyte will distribute between the phases according to its partition coefficient which is also called the distribution ... consisting of at least two immiscible liquids may be employed to provide the proper selectivity for the desired separation. ... phase chromatography, and the non-polar stationary phase chromatography became "reversed" phase chromatography. In reversed- ...
Chromatography
... a physical method of separation that distributes components to separate between two phases, one stationary (stationary phase), ... components of the sample separate in the column due to their partitioning coefficient between the two immiscible liquid phases ... Reversed-phase chromatography (RPC) is any liquid chromatography procedure in which the mobile phase is significantly more ... it is forward phase chromatography, and if it is non-polar (C-18) it is reverse phase. Column chromatography is a separation ...
Partition coefficient
Brodsky J, Ballschmiter K (1988). "Reversed phase liquid chromatography of PCBs as a basis for calculation of water solubility ... "Determination of liquid-liquid partition coefficients by separation methods". (secondary). Journal of Chromatography A. 1037 (1 ... reverse-phase HPLC, and pH-metric techniques.: 280 In this method the solid particles present into the two immiscible liquids ... Partition coefficients can also be defined when one of the phases is solid, for instance, when one phase is a molten metal and ...
Glossary of chemistry terms
... under which various phases (e.g. solid, liquid, and vapor) occur or coexist. phase transition 1. A transformation of a chemical ... See also partition. 2. The separation of a component analyte from a matrix. extrinsic property Contents: Top 0-9 A B C D E F G ... freezing point The temperature at which a substance changes state from a liquid to a solid. Because freezing is the reverse of ... diastereomer dispersion A system in which particles of one material are distributed within a continuous phase of another ...
Liquid chromatography-mass spectrometry - Wikipedia
... is a method of physical separation in which the components of a liquid mixture are distributed between two immiscible phases, i ... Among these, the most widely used variant is the reverse-phase (RP) mode of the partition chromatography technique, which makes ... TSP was also more suitable for LC-MS applications involving reversed phase liquid chromatography (RT-LC). With time, the ... James, A. T.; Martin, A. J. P. (1952-03-01). "Gas-liquid partition chromatography: the separation and micro-estimation of ...
Partition coefficient
... Concepts inChemical Equilibria Acid dissociation constant Binding constant Chemical equilibrium ... Brodsky J, Ballschmiter K (1988). "Reversed phase liquid chromatography of PCBs as a basis for calculation of water solubility ... is the ratio of concentrations of a compound in the two phases of a mixture of two immiscible solvents at equilibrium.[1] Hence ... Hydrophobic drugs with high partition coefficients are preferentially distributed to hydrophobic compartments such as lipid ...
Extraction - Analytical Chemistry (ACS Publications) - PDF Free Download
... columns has been used in direct or reversed-phase partition chromatography for the determination of Hg and In. This technique ... of modifications of batch extractors include a micro separatory funnel in which separation of the aqueous and organic phases ... also apply to two phase systems with a n uncharged, distributing complex. PROCEDURES. The best demonstration of the usefulness ... T h e distribution of t h e extracting species itself between t h e two immiscible solvents is mathematically described in a ...
PEH:Emulsion Treating - PetroWiki
Electrically Aided Extraction and Phase Separation Equipment. Liquid-Liquid Extraction Equipment, J.C. Godfrey and M.J. Slater ... Strictly speaking, an emulsion is a heterogeneous liquid that consists of two immiscible liquids, one of which is intimately ... In some cases, three-phase transformers are used with multiple grids that are wired to accept different phases. To protect the ... If available, ion chromatography also may be used for chloride determination. Ion chromatography is extremely accurate for ...
Chemistry the science of Matter
It includes Liquid-liquid extraction, and Solid phase extraction. The distribution of a solute between two phases is an ... Its critical that the cell undergo a liquid-liquid phase separation in order for two different biological process to occur.. ... or to separate immiscible liquids. An example is the cream separator found in dairies. Very high speed centrifuges and ... partitions, and a thermodynamic operation removes or makes the partitions more permeable and it is isolated, then it ...
DAMNATORY
DAFT MONARCHISTS DAHL BEARSKINS SHOWMANSHIP DOORMAN REVERSED BITE FERROMAGNETISM OUTDODGED BEDAZZLED MORBIDLY ANTI REVERSES ... ABASED PROTESTS TENDENCIES FROGGIEST DODGY SCRFCHAR FAWNS FANCIEST BUYER BALDFACED MISTIME CROFT INIQUITOUSLY CUED FAZED ... NOTECASES FROWZY TRADING UNDERWRITERS LYRICS ARCKING INTERPRETIVE ARBITRAMENT TSUBA JABOTS MYOTATIC VISIT SNIFFED PHASES SWYER ... WRASTLE HUBCAPS RESCHEDULES IMPERII LOTTOS IMPERIL DAWDLERS INLANDS EXCERBATION ADMONISHED HUBBIES FUNFAIRS WORKMAN PARTITION ...
Chemical5
- Liquid chromatography-mass spectrometry (LC-MS) is an analytical chemistry technique that combines the physical separation capabilities of liquid chromatography (or HPLC) with the mass analysis capabilities of mass spectrometry (MS). Coupled chromatography - MS systems are popular in chemical analysis because the individual capabilities of each technique are enhanced synergistically. (wikipedia.org)
- Overall, the interface is a mechanically simple part of the LC-MS system that transfers the maximum amount of analyte, removes a significant portion of the mobile phase used in LC and preserves the chemical identity of the chromatography products (chemically inert). (wikipedia.org)
- The coupling of chromatography with MS is a well developed chemical analysis strategy dating back from the 1950s. (wikipedia.org)
- In GC, the analytes are eluted from the separation column as a gas and the connection with electron ionization (EI) or chemical ionization (CI) ion sources in the MS system was a technically simpler challenge. (wikipedia.org)
- [2] Hence both the partition and distribution coefficient are measures of how hydrophilic ("water loving") or hydrophobic ("water fearing") a chemical substance is. (chemeurope.com)
High2
- While the mobile phase in a LC system is a pressurized liquid, the MS analyzers commonly operate under high vacuum. (wikipedia.org)
- Hydrophobic drugs with high partition coefficients are preferentially distributed to hydrophobic compartments such as lipid bilayers of cells while hydrophilic drugs (low partition coefficients) preferentially are found in hydrophilic compartments such as blood serum. (chemeurope.com)