A validated HPLC stability-indicating method for the determination of diacerhein in bulk drug substance

A novel stability-indicating high-performance liquid chromatographic (HPLC) method was developed and validated for the assay of diacerhein in bulk forms. Diacerhein was found to degrade in alkaline and acidic conditions and also under oxidative stress. The drug was stable to dry heat and in presence of light. Resolution of drug, its potential impurities and degradation products were achieved on a RP18 (endcapped) column utilizing 0.1 M phosphoric acid and methanol (40:60, v/v) as eluent at the detection wavelength of 254 nm. The validation studies were carried out fulfilling International Conference on Harmonisation (ICH) requirements. The procedure was found to be specific, linear, precise (including intermediate precision), accurate and robust.