Development and Validation of a Thin-Layer Chromatographic-Densitometric Method for the Analysis of Clotrimazole Vaginal Tablets
A thin-layer chromatography (TLC) method for the analysis of clotrimazole was developed and validated according to the International Conference on Harmonization (ICH) and the United States Pharmacopeia (USP) guidelines. The developed method will be used for a qualitative and quantitative analysis of clotrimazole in vaginal tablets. The method was developed using mobile phase containing toluene-acetone (15:10 v/v) on precoated TLC silica gel 60 F254 glass plates at a detection wavelength of 215 nm using reflectance absorbance and saturation time of 20 min. Densitometric analysis showed clotrimazole being retained at RF of 0.27. The method had acceptable level of specificity where no interference was observed between clotrimazole peaks to that of blank. The calibration curve of clotrimazole was estimated using both linear and polynomial regression function in the range of 1000–2400 ng spot−1 with regression coefficient,r2, of 0.992 for linear and 0.999 for polynomial regression. The accuracy at nominal concentration of clotrimazole was found to be 99.14%, and % RSD was 1.13% for repeatability and 1.30% for intermediate precision that involved two analysts. The developed analytical method is useful for the determination of clotrimazole in the finished drug formulation. Also it helps to identify substandard and fake medicines labeled as clotrimazole during postmarketing surveillance of the drug and especially in resource-constrained countries.