9525821 Lee This proposal is on research to develop capillary immunophoresis as an analytical technique to assess microheterogeneity in pharmaceutical proteins, including variations in post- translational modifications and degradation products. The technique consists of coupling a capillary electrophoresis system with an immunoreagent reaction capillary post-system which incorporates laser-induced fluorescence detection. Specifically it is proposed to study: (1) the relationship between separation conditions and separation resolution of protein variants in capillary zone electrophoresis and capillary isoelectric focusing, (2) the quantitative dependence of applied electric field strengths, capillary dimensions, and solution ionic strengths on the effectiveness of protein transfer and mixing of protein variants with antibodies in a post-capillary immunoreactor, and (3) the direct sensing of the antigen (protein variants)-antibody reaction by measuring the induced electrostatic potentials and pH changes around the antigen- antibody complexes. ***
