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SDS-PAGE
SDS-PAGE (sodium dodecyl sulfate–polyacrylamide gel electrophoresis) is a Discontinuous electrophoresis, discontinuous electrophoretic system developed by Ulrich K. Laemmli which is commonly used as a method to separate proteins with molecular masses between 5 and 250 Kilodalton, kDa. The combined use of sodium dodecyl sulfate (SDS, also known as sodium lauryl sulfate) and polyacrylamide gel allows to eliminate the influence of structure and charge, and proteins are separated solely on the basis of differences in their molecular weight. Properties SDS-PAGE is an electrophoresis method that allows protein separation by mass. The medium (also referred to as ′matrix′) is a polyacrylamide-based discontinuous gel. The polyacrylamide-gel is typically sandwiched between two glass plates in a slab gel. Although tube gels (in glass cylinders) were used historically, they were rapidly made obsolete with the invention of the more convenient slab gels. In addition, SDS (sodium dodecy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Blot
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detecting the proteins, this technique is also utilized to visualize, distinguish, and quantify the different proteins in a complicated protein combination. Western blot technique uses three elements to achieve its task of separating a specific protein from a complex: separation by size, transfer of protein to a solid support, and marking target protein using a primary and secondary antibody to visualize. A synthetic or animal-derived antibody (known as the primary antibody) is created that recognizes and binds to a specific target protein. The electrophoresis membrane is washed in a solution containing the primary antibody, before excess antibody is washed off. A secondary antibody is added which recognizes and binds to the primary antibod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Structure
Protein quaternary structure is the fourth (and highest) classification level of protein structure. Protein quaternary structure refers to the structure of proteins which are themselves composed of two or more smaller protein chains (also referred to as subunits). Protein quaternary structure describes the number and arrangement of multiple folded protein subunits in a multi-subunit complex. It includes organizations from simple dimers to large homooligomers and complexes with defined or variable numbers of subunits. In contrast to the first three levels of protein structure, not all proteins will have a quaternary structure since some proteins function as single units. Protein quaternary structure can also refer to biomolecular complexes of proteins with nucleic acids and other cofactors. Description and examples Many proteins are actually assemblies of multiple polypeptide chains. The quaternary structure refers to the number and arrangement of the protein subunits wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Dodecyl Sulfate
Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is an organic compound with the formula . It is an anionic surfactant used in many cleaning and hygiene products. This compound is the sodium salt of the 12-carbon an organosulfate. Its hydrocarbon tail combined with a polar " headgroup" give the compound amphiphilic properties that make it useful as a detergent. SDS is also component of mixtures produced from inexpensive coconut and palm oils. SDS is a common component of many domestic cleaning, personal hygiene and cosmetic, pharmaceutical, and food products, as well as of industrial and commercial cleaning and product formulations. Physicochemical properties The critical micelle concentration (CMC) in water at 25 °C is 8.2 mM, and the aggregation number at this concentration is usually considered to be about 62. The micelle ionization fraction (α) is around 0.3 (or 30%). Applications Cleaning and hygiene SDS is mai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discontinuous Electrophoresis
Discontinuous electrophoresis (colloquially ''disc electrophoresis'') is a type of polyacrylamide gel electrophoresis. It was developed by Ornstein and Davis. This method produces high resolution and good band definition. It is widely used technique for separating proteins according to size and charge. Method In this method, the gel is divided into two discontinuous parts, resolving and stacking gel, both have different concentrations of polyacrylamide. The one with lower concentration is stacked on top of the one with higher concentration. Discontinuity is based on four parameters: gel structure, pH value of the buffer, ionic strength of the buffer, and the nature of the ions in the gel and electrode buffer. The electrode buffer contains glycine. Glycine has very low net charge at pH 6.8 of stacking gel, so it has low mobility. The proteins are separated according to the principle of isotachophoresis and form stacks in the order of mobility (stacking effect). Mobility depends on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetrimonium Bromide
Cetrimonium bromide ( C16H33)N(CH3)3r; cetyltrimethylammonium bromide; hexadecyltrimethylammonium bromide; CTAB) is a quaternary ammonium surfactant. It is one of the components of the topical antiseptic cetrimide. The cetrimonium (hexadecyltrimethylammonium) cation is an effective antiseptic agent against bacteria and fungi. It is also one of the main components of some buffers for the extraction of DNA. It has been widely used in synthesis of gold nanoparticles (''e.g.'', spheres, rods, bipyramids), mesoporous silica nanoparticles (''e.g.'', MCM-41), and hair conditioning products. The closely related compounds cetrimonium chloride and cetrimonium stearate are also used as topical antiseptics and may be found in many household products such as shampoos and cosmetics. CTAB, due to its relatively high cost, is typically only used in select cosmetics. As with most surfactants, CTAB forms micelles in aqueous solutions. At 303 K (30 °C) it forms micelles with aggregation nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Persulfate
Ammonium persulfate (APS) is the inorganic compound with the formula (NH4)2S2O8. It is a colourless (white) salt that is highly soluble in water, much more so than the related potassium salt. It is a strong oxidizing agent that is used as a catalyst in polymer chemistry, as an etchant, and as a cleaning and bleaching agent. Preparation and structure Ammonium persulfate is prepared by electrolysis of a cold concentrated solution of either ammonium sulfate or ammonium bisulfate in sulfuric acid at a high current density.F. Feher, "Potassium Peroxydisulfate" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 390. The method was first described by Hugh Marshall. The ammonium, sodium, and potassium salts adopt very similar structures in the solid state, according to X-ray crystallography. In the ammonium salt, the O-O distance is 1.497Å. The sulfate groups are tetrahedral, with three short S-O distances near 1.44Å and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
16-BAC
Cetalkonium chloride (CKC) is a quaternary ammonium compound of the alkyl-benzyldimethylammonium chloride family, the alkyl group having a chain length of C16 (16 carbons). It is used in pharmaceutical products either as an excipient (Cationorm, Retaine MGD) or as an active ingredient ( Bonjela, Pansoral). It may be found in very small amount in the excipient benzalkonium chloride mixture (typically less than 5% of the total mixture). Cetalkonium chloride is purchased as a raw material in dry form as a white powder. Applications Cetalkonium chloride can be used in different applications depending on its concentration. Anti-infective agent It can be used as an active ingredient to relieve the pain of mouth ulcers and denture sores in buccal solutions or gels such as Pansoral or in Bonjela. The usual concentration in these products is 0.01% (w/w). However, it isn't known as a potent bactericidal compound, mainly because of its low solubility in water. For example, US and E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-link
In chemistry and biology a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural polymers (such as proteins). In polymer chemistry "cross-linking" usually refers to the use of cross-links to promote a change in the polymers' physical properties. When "crosslinking" is used in the biological field, it refers to the use of a probe to link proteins together to check for protein–protein interactions, as well as other creative cross-linking methodologies. Although the term is used to refer to the "linking of polymer chains" for both sciences, the extent of crosslinking and specificities of the crosslinking agents vary greatly. As with all science, there are overlaps, and the following delineations are a starting point to understanding the subtleties. Polymer chemistry Crosslinking is the general term for the process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Equilibrium
In a chemical reaction, chemical equilibrium is the state in which both the Reagent, reactants and Product (chemistry), products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system. This state results when the forward reaction proceeds at the same rate as the Reversible reaction, reverse reaction. The reaction rates of the forward and backward reactions are generally not zero, but they are equal. Thus, there are no net changes in the concentrations of the reactants and products. Such a state is known as dynamic equilibrium. Historical introduction The Concept learning, concept of chemical equilibrium was developed in 1803, after Claude Louis Berthollet, Berthollet found that some chemical reactions are Reversible reaction, reversible. For any reaction mixture to exist at equilibrium, the reaction rate, rates of the forward and backward (reverse) reactions must be equal. In the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protease
A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the formation of new protein products. They do this by cleaving the peptide bonds within proteins by hydrolysis, a reaction where water breaks bonds. Proteases are involved in many biological functions, including digestion of ingested proteins, protein catabolism (breakdown of old proteins), and cell signaling. In the absence of functional accelerants, proteolysis would be very slow, taking hundreds of years. Proteases can be found in all forms of life and viruses. They have independently evolved multiple times, and different classes of protease can perform the same reaction by completely different catalytic mechanisms. Hierarchy of proteases Based on catalytic residue Proteases can be classified into seven broad groups: * Serine protea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Half-life
Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the blood plasma, and is denoted by the abbreviation t_. This is used to measure the removal of things such as metabolites, drugs, and signalling molecules from the body. Typically, the biological half-life refers to the body's natural cleansing through the function of the liver and through the excretion of the measured substance through the kidneys and intestines. This concept is used when the rate of removal is roughly exponential. In a medical context, half-life explicitly describes the time it takes for the blood plasma concentration of a substance to halve (''plasma half-life'') its steady-state when circulating in the full blood of an organism. This measurement is useful in medicine, pharmacology and pharmacokinetics because it helps ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBC Membrane Proteins SDS-PAGE Gel
RBC may refer to: Media and arts * ''RBK Daily'', a general business newspaper published in Moscow, Russia. * RBK Group, a large Russian media group * RBC Ministries, now Our Daily Bread Ministries, a Christian media outlet in Grand Rapdis, Michigan * RBC Radio, the former name of Easy 96, a sub-channel radio station providing Asian Indian programming in New York City * RBC Records, an American independent record label * RBC Theatre, in the Living Arts Centre, Mississauga, Ontario, Canada * RBK TV, a business news channel in Russia * Regional Broadband Consortium, a UK entity for development of broadband to schools * Rhodesian Broadcasting Corporation, now the Zimbabwe Broadcasting Corporation * Ryukyu Broadcasting Corporation, a Japanese television and radio station * Radio Beijing Corporation, a family of municipal radio stations in Beijing, China Computing * Real business-cycle theory, a class of classical macroeconomics models * Recognition-by-components theory, a bottom-up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
