Stability-Indicating Densitometric HPTLC Method for Qualitative and Quantitative Analysis of Hydroquinone in Commercial Whitening Creams

A densitometric high-performance thin-layer chromatographic (HPTLC) method for analysis of hydroquinone has been developed and validated. Chromatography was performed on aluminum foil-backed silica gel 60 F-254 plates with chloroform methanol 85:15 (% v/v) as mobile phase. This system furnished a compact band for hydroquinone at R-F 0.51. Hydroquinone was quantified densitometrically at 289 nm. The limits of detection (LOD) and quantification (LOQ) were 38.50 and 115.50 ng per band, respectively. High precision and accuracy were achieved. The method was used for both qualitative and quantitative analysis of hydroquinone in commercial formulations. Because the method can effectively separate the hydroquinone in the presence of its degradation products, it can be used as a stability-indicating method.