ANALYSIS OF MONOCLONAL-ANTIBODIES BY SODIUM DODECYL SULFATE-CAPILLARY GEL-ELECTROPHORESIS WITH REFERENCE TO QUANTITATION OF HALF-ANTIBODY

Sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE) was recently introduced as a protein analytical method based on the separation by size of protein-SDS complexes migrating through a molecular sieving matrix. It is an instrumental technique analogous to the classical SDS-polyacrylamide gel electrophoresis (PAGE) method using slab gels of polyacrylamide. SDS-CGE has potential advantages of automation of data acquisition and quantitation of the components of the analyte. SDS-CGE was applied to the analysis of recombinant monoclonal antibodies being developed as potential therapeutics. In addition to detecting protein contaminants, this method was useful for determining the amount of incompletely assembled antibody that often occurs in the production of certain types of antibody. Separation and quantitation of antibody species lacking proper disulfide links between the constituent protein chains were demonstrated. SDS-CGE was found to be a reproducible, easy-to-perform technique for characterizing the quality of monoclonal antibody products.