Simple RP-HPLC method for estimation of diazepam in tablet dosage form

A simple reverse phase HPLC method was developed and validated for the determination of diazepam present in pharmaceutical dosage form. A Hypersil ODS C-18 column (250 × 4.6 mm, packed with 5 microns) is used as stationary phase. An isocratic mode with mobile phase consisting of acetonitrile, methanol and 1% phosphate buffer (pH-3) in ratio of 18:58:24 (v/v/v) at a flow rate of 1 ml/min and effluent was monitored at 232 nm. Chromatogram showed a peak of DZP at retention time of 6.23 ± 0.002 min. The linearity range was found to be 2-20 μg/ml. The method was validated for linearity, accuracy, precision, limit of detection, limit of quantitation, robustness and ruggedness. Recovery of DZP was found to be in the range of 99.4-100.3%. The limit of detection and limit of quantitation for estimation of DZP was found to be 0.898 μg/ml and 2.72 μg/ml, respectively. Proposed method was successfully applied for the quantitative determination of DZP in pharmaceutical dosage forms.