Development and Validation of a New HPLC Method for In-Vitro Studies of Mebudipine in Pharmaceutical Formulations

A simple and sensitive method has been developed for the analysis of mebudipine in pharmaceutical formulations. According to this, mebudipine is analyzed by reverse phase high performance liquid chromatography (HPLC) using a system equipped with a C18 column and a UV detector operating at a wavelength of 290 nm. The mobile phase is a mixture of methanol, water, and acetonitrile (70 : 25 : 5, v/v/v). Under these conditions, separation of the drug was achieved in less than 20 min. For the assay, one tablet is dissolved in 50 ml methanol and 20 μl of this solution is injected into the HPLC column. The medium for dissolution testing was a mixture of water, 0.1 N HCl, gastric fluid, intestinal fluid, and sodium dodecyl sulfate in various concentrations (1, 2, and 3%). The tests were performed by using 500 ml medium in a paddle apparatus operating at a stirring rate of 75 rpm. Sampling aliquots of 5 ml were withdrawn at 30, 45, 60, 75 and 90 min. The drug release was evaluated by HPLC. It was found that 3% SDS ensured maximum release of mebudipine. The method was linear in the range of 0.5 – 500 μg/mL (R ² = 0.9992). The limits of detection and quantitation were 0.6 and 0.7 μg/mL for dissolution test and 1.4 and 1.5 μg/mL for assay, respectively.