chapter  6
97 Pages

Affinity chromatography

In principle, affinity chromatography is a form of adsorption chromatography, which is based on the exceptional ability of biological molecules to form specifically and reversibly complexes with complementary substances immobilized on a solid matrix. These are generally called ligands, affinity ligands or affinants. The complexes of enzymes with their inhibitors, substrates, cofactors, effectors, antibodies with their antigens or haptens, lectins with glycoproteins or polysaccharides, complexes of nucleic acids, hormones and toxins with receptors, transport proteins with vitamins or sugars, etc., may be mentioned as examples (Lowe and Dean, 1974; Jakoby and Wilchek, 1974; Scouten, 1981; Mohr and Pommerening, 1985; Turková, 1978, 1993; Hermanson et al., 1992; Schott, 1984; Wilchek and Bayer, 1990). The complexes of biologically active compounds with dyes are described in dye ligand affinity chromatography (Vijayalakshmi and Bertrand, 1989), with metal ions in metal chelate affinity chromatography (Porath, 1975), etc. These different approaches are grouped under the generic name “Pseudobio specific ligand affinity chromatography” was discussed in details in a review by M.A.Vijayalakhsmi (1989). If one of the components of the complex is immobilized, a specific sorbent is formed for the second component assuming that the conditions necessary for the formation of this complex exist. The binding sites of the immobilized substances must be sterically accesible after their binding to the solid support, and they must not be deformed by immobilization.