High-performance Thin-layer Chromatography for the Determination of Nimesulide in Human Plasma, and its Use in Pharmacokinetic Studies

A rapid and sensitive high-performance thin-layer chromatographic assay has been developed for the measurement of nimesulide in human plasma. Its use for pharmacokinetic studies has been evaluated. The method includes a single-stage extraction procedure without the use of an internal standard. Analysis was performed on plasma containing known amounts of the drug, on drug-free plasma, and on plasma containing an unknown quantity of the drug. Known amounts of extract and nimesulide (100 and 200 ng, as external standard) were spotted on precoated silica-gel 60F254 plates by means of a Camag Linomat IV autosampler. Quantification was achieved using a Camag TLC scanner 3. The recovery of the method was 97.10 +/- 2.22%. The method was applied for the determination of plasma levels and pharmacokinetic parameters of nimesulide after oral administration of two formulations (100 mg) in healthy volunteers. The method is a sensitive, economical, rapid and specific assay for nimesulide in human plasma, and is suitable for pharmacokinetic studies after therapeutic doses.