Anuradha H Mahapatra

  The present work describes the development of stability indicating assay method for Diacerein and Aceclofenac in their combined dosage form that would provide helpful information to the manufacturers. Stress studies were conducted on the drug substance and product under the ICH prescribed stress conditions viz. hydrolysis, oxidation, humidity, photolysis, thermal stress. The separation of the drug from its degradation products, trials were made by taking acetonitrile: water, acetonitrile: phosphate buffer, acetonitrile: phosphoric acid in various blends. Separation was achieved using C-18 column and a mobile phase comprising of Acetonitrile: Phosphoric acid 0.1 M (61: 39) at a flow rate of 1.5 mL/min. The detection wavelength was 260 nm. The drug showed sufficient decomposition under alkaline hydrolysis (0.05 N NaOH), acidic hydrolysis (0.05 N HCl), neutral hydrolysis (distilled water), and oxidative hydrolysis (6% H2O2). The drug was found to be moderately sensitive to humidity studies (75 % RH), photochemical studies (UV 254 nm), and thermal studies (600C). Recovery studies were also carried out for both the drugs and the mean percent recovery were found to be 100.69 for diacerein and 99.15 for aceclofenac. Mean percent estimation in marketed formulation gave 99.63% for diacerein and 100.04% for aceclofenac. The above method was validated for accuracy, precision, ruggedness, limit of detection, limit of quantitation and was found to be satisfactory for routine analysis of diacerein and aceclofenac in their combined dosage form in the presence of their degradation products.   Key words: Aceclofenac, Diacerein, Stress Degradation, Stability Indicating, Validation