Development and validation of HPTLC method for simultaneous estimation of curcumin and galangin in polyherbal capsule dosage form

Simple and precise HPTLC methods were developed for the simultaneous estimation of two anti-inflammatory drugs (curcumin and galangin). The method was tailored to analyze both drugs in their commercial dosage form (capsules) with no interference from ingredients. Chromatographic separation was performed over precoated TLC plates (60 F254, 20 cm × 10 cm, 250 μm thickness, Merck, Darmstadt, Germany) via a linear ascending technique using n-hexane, ethyl acetate, acetic acid, and methanol as the mobile phase. Detection and quantification was achieved at 404 nm through spectro-densitometric analysis. Analytical performance of the proposed HPTLC method was validated according to the ICH guidelines with respect to the linearity, accuracy, precision, detection and quantitation limits, robustness and specificity. The calibration curves were linear with the limits of 80-450 and 200-1200 ng/spot for CU and GA, respectively, with correlation coefficients (r2) >0.9998. The limits of detection were 18.31 and 40.50 ng/spot for CU and GA, respectively. The validated HPTLC method was successfully applied to the simultaneous determination of CU and GA in the commercial polyherbal formulation.