Rapid and sensitive method for determination of nimesulide in human plasma by high-performance liquid chromatography

A rapid and sensitive high-performance liquid chromatographic method for determination of nimesulide in human plasma has been developed. The chromatographic system uses a reversed-phase C-18 column with UV-Vis detection at 230 nm. Mobile-phase consisted of phosphate buffer (pH 5.5)-methanol-acetonitrile (50:20:30, v/v) at a flow-rate of 1.4 ml/min. Nimesulide was extracted in a single step into dichloromethane. The overall mean extraction recoveries were above 98% for both inter- and intra-assay reproducibility,with CVs from 0.3 to 1%. The calibration curve was linear in the concentration range of 0.05-5 mu g/ml, and the lower limit of detection was 30 ng/ml. This simple and sensitive method allows for determination of the range of plasma concentrations that is observed after administration of clinically relevant doses of nimesulide. (C) 1999 Elsevier Science B.V. All rights reserved.