Preliminary studies of immunoaffinity doped capillary zone electrophoresis (ID-CZE)

Preliminary experiments were performed to test the feasibility of developing a new immuno-analytical technique, Immunoaffinity Doped Capillary Zone Electrophoresis (ID-CZE). This technique combines the high sensitivity of CZE and the selectivity of immune affinity electrophoresis. Alteration of the electrophoretic mobility of an analyte by selective interaction with an affinity reagent doped into the mobile phase was the primary emphasis of this investigation. Three different systems were investigated: avidin-biotin (a non-immunogenic system), FITC-anti-FITC (a hapten-anti-hapten immunogenic system), and IgG-anti-IgG (an antigen-anti-antigen immunogenic system). The avidin-biotin system showed that the analyte's mobility could be altered in a doped mobile phase. The complex formed by the interaction of FITC with anti-FITC was presumably a FITC labeling product and not the result of an affinity interaction. No definitive IgG-anti-IgG complex was visualized. This result was most likely due to either complex and free reactant mobility similarities or poor detection limits. Experimental conditions are studied and calculations are presented that could be used to determine fundamental parameters such as Ka values.