Capillary electrophoresis based immunoassay for monoclonal antibody with diode laser induced fluorescence detection

A capillary electrophoresis based immunoassay (CEIA) for monoclonal antibod y using diode laser induced fluorescence (LIF) detection was described. A d irect assay for monoclonal anti-BSA in mouse serum was used as a model. BSA was labeled with Cy5 and used as the immunoreagent. The 635 nm line of a d iode laser was used as the excitation source for LIF detection. The calibra tion curve for anti-BSA in mouse serum had a linear dynamic range of 4-40 n M. The concentration limit of detection (LOD) was 1.2 nM. Incubation time a nd CE conditions such as buffer concentration, pH and separation voltage we re optimized, and the performances of different lasers as excitation source s were also compared.