Quantitative analysis of nimesulide in plasma by thin-layer chromatography: Application to pharmacokinetic studies in man

Abstract

A thin-layer chromatographic (TLC) method for quantitative analysis of nimesulide in human plasma has been developed, validated, and applied to a pharmacokinetic study of healthy volunteers. A previously published method has been modified and simplified (instead of two-step sample preparation a single step extraction procedure was employed) which makes the new method timesaving. Nimesulide plasma concentrations were analyzed after single-step extraction with dichloromethane. The sample preparation procedure described enables efficient extraction - recoveries were 99 +/- 8% (mean +/- SD). Chromatography was performed on silica gel 60 F-254 TLC plates, developed with toluene-acetone, 100 + 10 (nu/nu) and evaluated densitometricatly at lambda = 310 nin in reflectance-absorbance mode. The R-F was 0.5025. The method presented is characterized by high sensitivity (0.1 mg L-1) and within-run and day-to-day coefficients of variation of 2.8-4.5% and 4.8-8.5%, respectively. The method was used to determine the pharmacokinetic profile of nimesulide in healthy volunteers after oral administration.