Protein Purification by Affinity Chromatography

Affinity chromatography is a method which depends essentially on the interaction between the molecule to be purified and a solid phase that will allow the separation of contaminants. Lectins are carbohydrate-binding proteins which can be purified by affinity chromatography; also, the presence of multiple molecular forms of lectins in a preparation can be separated. Immobilized lectins have been useful to affinity protein purification. In immunoaffinity chromatography an antibody or an antigen is immobilized on a support so as to purify the protein against which the antibody was developed. Monoclonal antibodies are extremely useful as immunosorbents for purification of antigen. Immobilization of monoclonal antibody on a suitable material to the column produces a support that will bind with high selectivity to protein against which the antibody was developed. Affinity chromatography containing DNA is a highly specific and important technique for the purification of DNA-binding proteins involved in the transcription, replication and recombination. The success of affinity chromatography depends on the conditions used in each chromatographic step. So, the optimization of protocol is essential to achieve optimal protein purification with maximum recovery.