Quantitative Analysis of Nimesulide in Plasma by Thin-Layer Chromatography: Application to Pharmacokinetic Studies in Man

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. Apreviously 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 time-saving. Nimesulide plasma concentrations were analyzed after singlestep extraction with dichloromethane. The sample preparation procedure described enables efficient extraction—recoveries were 99 ± 8% (mean ± SD). Chromatography was performed on silica gel 60 F254 TLC plates, developed with toluene—acetone, 100 + 10 ((v/v)) and evaluated densitometrically at λ = 310 nm in reflectance—absorbance mode. The RF 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.