title: Feasibility studies for simultaneous immunochemical multianalyte drug assay by capillary electrophoresis with laser-induced fluorescence.
abstract: We present a method for the simultaneous quantification of multiple drug analytes in urine, based on combining immunochemical binding with capillary electrophoretic separation. Two fluorescent drug-cyanine (Cy) dye conjugates were prepared as competing species for the immunoassay. Morphine was derivatized with Cy5 (lambda max = 652 nm, epsilon = 215,000 mol-1cm-1 L), phencyclidine (PCP) with Cy5.5 (lambda max = 675 nm, epsilon = 200,000 mol-1cm-1L). The high-efficiency resolving power of the capillary electrophoresis system (20 microns x 27 cm column) separated the individual labeled drugs, and the antigen-antibody complexes were detected by laser-induced fluorescence (laser: 10 mW He-Ne at 632.8 nm) with Cy5 diacid as internal standard. Simultaneous competitive immunoassay of morphine and PCP in urine showed that the free labeled-drug peak areas were proportional to the concentrations of the drug species present in the urine sample. This immunoassay can be performed routinely and reproducibly in < 5 min with analytical detection limits of 4 nmol/L for PCP and 40 nmol/L for morphine.
authors.affiliation: Advanced Technology Center, Beckman Instruments Inc., Fullerton, CA 92634.
authors.forename: F T
authors.initials: FT
authors.lastname: Chen
authors.forename: R A
authors.initials: RA
authors.lastname: Evangelista
mesh_terms: D000937:Antigen-Antibody Reactions; D004586:Electrophoresis / Q000379:methods*; D005240:Feasibility Studies; D005453:Fluorescence; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007834:Lasers; D009020:Morphine / Q000652:urine*; D010622:Phencyclidine / Q000652:urine*; D012680:Sensitivity and Specificity
chemical_list: D009020:Morphine; D010622:Phencyclidine