CHARACTERIZATION OF CHARGE-MODIFIED AND FLUORESCEIN-LABELED ANTIBODY BY CAPILLARY ELECTROPHORESIS USING LASER-INDUCED FLUORESCENCE - APPLICATION TO IMMUNOASSAY OF LOW-LEVEL IMMUNOGLOBULIN-A

An affinity-purified and fluorescein-labeled antibody was chemically m odified to alter its electrophoretic mobility. The functional activity of the resulting modified and fluor labeled antibody appeared was pre served. Immunoassay is carried out by the addition of an appropriate a mount of the labeled antibody to a sample containing the antigen. Sepa ration of the antigen-bound and free labeled antibody was performed by capillary electrophoresis with laser-induced fluorescence detection. Both free and antigen-bound labeled antibody species may be analyzed s imultaneously. Quantitation of the immunoassay is achieved with an on- line data analysis.