Simultaneous Determination of Ruscogenin, Neoruscogenin, Trimebutin, and Parabens in Cream Formulation by Reverse Phase High Performance Liquid Chromatography

A simple and stability indicating reverse-phase high-performance liquid chromatographic method for the simultaneous analysis of ruscogenin, neoruscogenin, trimebutine, and parabens including methylparaben and propylparaben has been developed and validated. The separations were performed using a C18 column (250 × 4.6 mm, 5 μm i.d.). The column temperature was set to 25 °C. The mobile phase consisted of acetonitrile (mobile phase B) and 20 mM phosphate buffer pH 3.9 (mobile phase A) and was mixed in gradient elution mode using a binary pump. The developed method was validated according to the requirements of the ICH Q2(R2) guideline. In all cases, the method was found selective for all active substances and parabens. The limit of detection and limit of quantification values ranged from 0.02 to 0.45 µg mL^–1 and from 0.06 to 1.35 µg mL^–1, respectively. The intraday and interday accuracy (relative error ≤ 1.89) and precision (relative standard deviation ≤ 1.99) values of the method for all compounds were found in the limits. Based on the validation studies, the developed method was found to be selective (peak purity index ≥ 0.9904), sensitive, accurate, precise, and robust. The developed method was successfully applied for the quantification of Ruscogenin, neoruscogenin, trimebutine and methylparaben, propylparaben from the semi-solid dosage form.