Improved high-performance liquid chromatographic determination of debrisoquine and 4-hydroxydebrisoquine in human urine following direct injection

A sensitive and specific reversed-phase high-performance liquid chromatographic assay was developed for the determination of debrisoquine and 4-hydroxydebrisoquine in urine. The urine samples were directly injected following an ether clean-up step which eliminated interference. Separation of the analytes was achieved using a mobile phase consisting of acetonitrile-methanol-0.02 M heptane sulfonic acid (pH 3.0) (6:37:57) and a mu Bondapak C-18 analytical column. The assay utilizes fluorescence detection at 208 nm (ex) and 562 (em). The within-day and between-day coefficients of variation were less than or equal to 10% for both components and accuracy was within 12%. The method is suitable for pharmacogenetic studies utilizing debrisoquine.