A Stability-indicating HPLC Method for Assay of Lercanidipine Hydrochloride in Tablets and for Determining Content Uniformity

A simple, precise and accurate HPLC method has been developed and validated for assay of lercanidipine hydrochloride in tablets and for determination of content uniformity. An isocratic separation was achieved using a Chromasil YMC Pack C(8), 150 × 4.6 mm i.d., 5µm particle size columns with a flow rate of 1 ml/min and using a UV detector to monitor the elute at 240 nm. The mobile phase consisted of 0.02 M ammonium dihydrogen phosphate buffer:methanol (35:65, v/v) with pH 3.5 adjusted with phosphoric acid. The method was validated for specificity, linearity, pre-cision, accuracy, robustness and solution stability. The specificity of the method was deter-mined by assessing interference from the placebo and by stress testing of the drug (forced degradation). The method was linear over the concentration range of 20-80 µg/ml (r(2)= 0.9992) with a limit of detection and quantitation of 0.1 and 0.3 µg/ml respectively. Intraday and interday system and method precision were determined and accuracy was between 99.3-101.9 %. The method was found to be robust and suitable for assay of lercanidipine hydrochloride in a tablet formulation and for determination of content uniformity. Degradation products resulting from the stress studies did not interfere with the detection of lercanidipine hydrochloride and the assay is thus stability-indicating.