Ex vivo conversion of prodrug prothionamide to its metabolite prothionamide sulfoxide with different extraction techniques and their estimation in human plasma by LC–MS/MS

The present work reports an ex vivo conversion study of prothionamide to its active metabolite prothionamide sulfoxide in human plasma during sample preparation by three conventional extraction techniques. Results: The chromatography was done on a Hypersil™ Gold C18 (50 × 2.1 mm, 3.0 µm) column using 0.1% acetic acid and acetonitrile (20:80, v/v) as the mobile phase. Quantitation of the analytes was done by MS/MS in the positive ionization mode. The method was validated over a wide concentration range of 30 to 6000 ng/ml for prothionamide and 50 to 10,000 ng/ml for prothionamide sulfoxide. The recovery for both the analytes...