The present work describes validated high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) methods for the simultaneous determination of colchicine and khellin. The isocratic reversed-phase HPLC separation was performed on a 5 µm C18 column (Luna, Phenomenex, Torrance, CA). Good resolution between colchicine and khellin was achieved using a mixture of acetonitrile-10 mM NaH(2)PO(4) (pH 3.0, 35:65 v/v) as a mobile phase. Quantitation was achieved with ultraviolet detection at 245 nm based on peak area. The HPTLC separation was conducted on Merck HPTLC aluminum sheets of silica gel 60 F254 as stationary phase using methylene chloride-methanol (95:5 v/v) as a mobile phase. Quantification was also achieved using densitometric measurements at 245 nm. Both methods revealed reasonable validation parameters concerning selectivity, linearity, accuracy, precision and limits of detection and quantitation.
