Determination of lormetazepam in tablets using high-performance thin-layer chromatography, high-performance liquid chromatography, and derivative spectrophotometry methods

Abstract

This study describes the development and validation of some analytical methods as high-performance thin-layer chromatography (HPTLC), ultraviolet (UV)–densitometry, UV–high-performance liquid chromatography (HPLC), and derivative spectrophotometry elaborated for the estimation of lormetazepam in pharmaceutical formulations. HPTLC method was performed using silica plates, a mobile phase composed of acetonitrile‒water (6:4, v/v), and a densitometric detection at 241 nm. UV‒derivative spectrophotometry method was applied, and at first, the direct spectrum was recorded, then first-, second-, and third-derivative spectra were obtained and measured by peak-zero (P-0) or peak-peak (P-P) techniques. Moreover, HPLC method was performed using a Gemini C18 column and isocratic elution mode with a mobile phase composed of acetonitrile–water (65:35, v/v) and delivered at a flow rate of 0.5 mL min−1. In the case of HPTLC analysis, the quantification was achieved with acceptable precision (relative standard deviation [R...