Development of an ELISA to study the polymorphism of dextromethorphan oxidation in a French population

Simple, sensitive and selective enzyme immunoassays (ELISA) for monitoring urinary dextromethorphan and its major metabolite, dextrorphan, were developed. Dextromethorphan and dextrorphan hemisuccinates were linked to bovine serum albumin and specific antisera against each immunogen were raised in rabbits. The sensitivity of the ELISA was high (limit of detection 740 and 600 pg·ml−1 for dextromethorphan and dextrorphan, respectively). Intra- and interassay variation was <10%, and cross-reactivity between the two compounds was <1%.