Separation biomolecule

Additional techniques capable of separating biomolecules on the basis of molecular mass (e.g. ultrafiltration) may also be used to remove endotoxin from the product stream. 

Affinity chromatography is a very powerful technique which separates biomolecules according to differences in their biological function or chemical stracture. The stationary phase for affinity chromatography consists of a matrix to which ligands are covalently attached. 

Separating Biomolecules In studying a particular biomolecule (a protein, nucleic acid, carbohydrate, or lipid) in the laboratory, the biochemist first needs to separate it from other biomolecules in the sample—that is, to purify it. Specific purification techniques are described later in the text. However, by looking at the monomeric subunits of a biomolecule, you should have some ideas about the characteristics of the molecule that would allow you to separate it from other molecules. For example, how would you separate (a) amino acids from fatty acids and (b) nucleotides from glucose ... 

Example Chromatography was used to separate a mixture of biomolecules. The mixture was added to the stationary phase - paper - at a point that was marked as the origin. The mobile phase (eluent or solvent) - ethanol - was then added, and after several hours a number of spots were visible along the paper at distances of (i) 5 cm, (ii) 10 cm and (iii) 15 cm from the origin. During this time the mobile phase moved a total distance of 20 cm (the solvent front). From this, calculate the R/ values of each separated biomolecule ... 

Typically the solvent used as the mobile phase will be allowed time to move further along the stationary phase than the separated biomolecules. From this, and the formula above, R values will normally be calculated as values less than one. 

Chromatography separates biomolecules on the basis of ionic charge, solute partitioning, molecular size and/or adsorption properties. 

A large number of variants of gel electrophoresis are used in bioanalytical analysis to allow separation and characterization of biomolecules, in particular nucleic acids (DNA, RNA) and proteins. The term gel refers to the matrix used to separate biomolecules, and in most cases is a cross-linked polymer. 

Ultracentrifugation Is Valuable for Separating Biomolecules and Determining Their Masses... 

The PEG/water, PPG/water, and PVAL/water are among the most extensively studied water-soluble polymer solutions. These systems typically show a closed-loop phase behavior (Figure 16.4). Results for some ternary systems have been reported many of these data are for PEG/Dextran/water and PEG/water/salts and related systems, which are important for separating biomolecules such as proteins. Only few data for PEG or other hydrogen bonding polymer with mixed water solvents have been reported. 

R.D. Rogers and M.A. Eiteman. eds. Aqueous Biphasic Separations Biomolecules to Metal ions. Plenum, New York, 1995. 

The charge density of biomolecules is related to their electrophoretic mobility therefore, electrophoresis in a free solution capillary zone electrophoresis (CZE)) can be a method to separate biomolecules based on the charge density. The free solution electrophoretic mobility is a characteristic feature of each analyte, which is determined by the complicated balance among the electrical driving force on the analyte, electrical driving force on the counterions within the... 

Nanorods have also been used to isolate and separate biomolecules, due to their size compatibility, e.g. carbon nanotubes have been employed in gel electrophoresis methods to improve the separation of human serum proteins, and arrays of Sn02 nanowires are found to both unravel and separate long DNA molecules. Furthermore, biomolecules themselves have been engineered for use as nanowires, with a myriad of applications." " " ... 

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