Abstract
A simple and affordable high-performance thin-layer chromatographic (HPTLC) method has been established for simultaneous analysis of colchicine (CL) and gallic acid (GA), which are present together in a complex commercial polyherbal drug (Habb-e-Irqun-Nisa) in tablet dosage forms. The chromatographic separation was carried out on pre-coated silica gel 60 GF(254) plates with ethyl acetate/acetonitrile/water/formic acid/N-dimethylformamide 7.5:1:0.5:0.5:0.5 (v/v) as mobile phase. The plates were developed to a distance of 9.0 cm at ambient temperature. The developed plates were scanned and quantified at a single wavelength of maximum absorption at 360 and 287 nm for CL and GA, respectively. Experimental conditions such as band size, chamber saturation time, migration of solvent front, slit width, etc., were critically studied, and the optimum conditions were selected. The drug samples were satisfactorily resolved with R-f 0.35 +/- 0.02 for colchicine and 0.69 +/- 0.03 for gallic acid. The method was validated for linearity, accuracy, precision and specificity. The calibration plot was linear between 25 and 200 ng per band for CL and 100-800 ng per band for GA. The limits of detection and quantification for CL were 2.0 and 25.00 ng per band, respectively, whereas for GA, these were 10.00 and 100.00 ng per band, respectively. The proposed HPTLC method for estimation of CL and GA was found to be economic, simple, precise, sensitive and less time consuming than other chromatographic procedures and can be used for routine quality control of Habb-e-Irqun-Nisa and other polyherbal formulations containing these phytoconstituents.