IMMUNOLOGICAL ANALYSIS OF METHAMPHETAMINE ANTIBODY AND ITS USE FOR THE DETECTION OF METHAMPHETAMINE BY CAPILLARY ELECTROPHORESIS WITH LASER-INDUCED FLUORESCENCE

An accurate, simple and rapid immunoassay is demonstrated for the dete ction of methamphetamine in urine by capillary electrophoresis (CE) wi th laser-induced fluorescence (LIF). An aminobutyl derivative of metha mphetamine was conjugated with proteins, and used as an immunogen to p roduce antibodies for the essay. The methamphetamine derivative was al so labeled with fluorescein isothiocyanate (FITC) to compete with free methamphetamine in the sample for the antibody binding site. Levels o f free and antibody-bound FITC-labeled methamphetamine were monitored by performing CE-LIF using an untreated fused-silica column. This comp etitive immunoassay used antiserum instead of purified antibody or ant ibody fragment, yet was found to have good precision with a sensitivit y of lower than 20 ng/ml. Various antibodies were also screened, and c ross-reactivity of anti-MA antibody with methamphetamine analogues wer e also investigated. The results indicate that CE-LIF-based immunoassa y is a powerful tool for the screening and characterization of antibod y and may have possible applications in the detection of abused drugs in urine. (C) 1998 Elsevier Science B.V.