FULLY AUTOMATED-ASSAY FOR THE DETERMINATION OF SUMATRIPTAN IN HUMAN SERUM USING SOLID-PHASE EXTRACTION AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH ELECTROCHEMICAL DETECTION

A method is described for a fully automated, sensitive, accurate and p recise assay for the determination of sumatriptan in human serum. The assay consists of solid-phase extraction followed by reversed-phase HP LC with electrochemical detection. The extraction procedure has been f ully automated on a Zymate XP robot linked on-line to the HPLC system. The assay is linear over the analytical range 1-30 ng ml(-1) and sele ctive for sumatriptan with respect to endogenous plasma components and GR49336, the major circulating metabolite. The intra-assay data demon strate a maximum bias and precision across the calibration range of 10 % and 6.6%, respectively. The inter-assay data demonstrate a maximum b ias and precision across the calibration range of 6.7% and 8.8%, respe ctively. The extraction efficiency of the assay is approximately 90% a nd is constant across the calibration range. The assay was used for th e determination of sumatriptan in serum clinical samples and was shown to be robust in sustained use over several months. The use of a Zymat e XP robot allowed complete automation of the assay, which resulted in high-quality, high-throughput analyses.