Stability Indicating Fast LC Method for the Estimation of Impurities in Cephalexin for Oral Suspension

A fast, stability-indicating reversed phase liquid chromatographic method has been developed and subsequently validated for the estimation of impurities of Cephalexin. The developed method utilizes the chemistry of sub 2-μm C-18 column and mobile phase consisting of Potassium dihydrogen phosphate buffer-acetonitrile with gradient elution, at a flow rate of 1.0 mL per minute. The detection was carried out at 254 nm. As there are no simple Fast LC methods reported for the estimation of Impurities/degradants of Cephalexin in Pharmaceutical formulations, the current method was developed and validated. The method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification, ruggedness and robustness. This method has been successfully applied to pharmaceutical formulation and no interference from the excipients used the powder for suspension was found. As the proposed method could effectively separate the drug from its degradants/impurities, it can be employed as stability-indicating method for the determination of instability of the drug in bulk and pharmaceutical formulations.