Rapid High-Performance Liquid Chromatographic Method for the Analysis of Debrisoquine and 4-Hydroxydebrisoquine in Urine without Derivatization

A simple and rapid HPLC method has been developed for the simultaneous determination of debrisoquine (D) and its main metabolite, 4-hydroxydebrisoquine (4OHD) in urine, without derivatization of the compounds. Guanoxan is used as the internal standard. The chromatographic separation was accomplished with a mobile phase comprising 15% acetonitrile and 85% 8 mM phosphate buffer (pH 5) at a flow rate of 1 ml/min. The HPLC column was packed with 5 μm Spherisorb-CN. The eluant was monitored at 214 nm. The intra- and inter-assay coefficients of variation were less than 6%. The lowest limit of detection for D was 0.1 μg/ml and for 4OHD was 0.05 μg/ml. The method is suitable for determining the oxidation phenotype of populations and is presently being used to study the oxidation polymorphism in Maori and South Pacific Polynesians.