A SIMPLE (HPLC–UV) METHOD FOR THE QUANTIFICATION OF COLCHICINE IN BULK AND ETHOSOMAL GEL NANO-FORMULATION AND ITS VALIDATION

Objective: To develop and validate a stability-indicating reversed phase high-performance liquid chromatography (RP-HPLC) method for the determination of colchicine in bulk and ethosomal gel nano-formulation. Methods: The chromatographic conditions were optimized using stainless steel Hypersil Gold C-18 analytical column with the dimensions of 250 mm x 4.6 mm ID x 5 µm. The mobile phase consisted of acetonitrile and ammonium acetate buffer (20 mmol/l, pH=4.85) in the ratio of 32:68 v/v. The flow rate was set at 1 ml/min and the detection wavelength was 353 nm. The column was maintained at 30 °C and the injection volume was 10 µl. The stability of colchicine in different conditions was investigated by exposing the drug to stress degradation using acid, base, oxidation, heat and light. Results: There was no interference from excipients, impurities, dissolution media or degradation products at the retention time of colchicine 5.9 min indicating the specificity of the method. The limit of detection (LOD) and the limit of quantification (LOQ) were 8.64 ng/ml and 26.17 ng/ml respectively. The drug showed good stability under heat, acid, oxidation and light, but substantial degradation was observed under alkali condition . The procedure was validated for specificity, linearity, accuracy and precision. Conclusion: A simple, rapid, specific and stability-indicating HPLC–UV method for the determination of colchicine in the pure and ethosomal gel was successfully developed. The developed method was statistically confirmed to be accurate, precise, and reproducible.