The New RP-HPLC Method for Simultaneous Quantification of Cinnarizine, its Five Specified Impurities, Two Degradation Products with Two Antioxidants and Confirmation of all by HPLC-ESI-MS in Different Pharmaceutical Drug Formulations

To determine the safety and efficacy, we have developed and validated the RP-HPLC method for simultaneous quantification of cinnarizine, its five specified impurities and two degradation products in cinnarizine API, tablets and capsules and including two antioxidants in an oral suspension formulation. The chromatographic separation was achieved in gradient elution mode with 1.00mL/min flow on an Ascentis Express C18 (150mm, 4.6mm and 2.7µm particle size) column at 40.0°C column temperature using 0.05% acetic acid in mixtures of 10mM ammonium acetate and acetonitrile. All peaks are eluted within 30 minutes with a 10µL injection volume and detected at a 230nm wavelength. The results of the validation of the proposed RP-HPLC method as per ICH guidelines revealed that the method is specific, accurate, precise, linear and robust for quantification purposes. The recoveries for all specified impurities, degradation products and cinnarizine at a lower concentration were found in the range of 100.0±10.0%. While the assay values were within 100.0±2.0% for cinnarizine and antioxidants (methylparaben and propylparaben). The LOD and LOQ were 0.1125µg/mL and 0.1875µg/mL, respectively. The linearity curves for all the ten analytes mentioned above showed good linearity (r≥0.999). This research work presents the first RP-HPLC method for simultaneous quantification of all ten analytes with unknown impurities, as well as an HPLC-ESI-MS method for correct identification and confirmation of results.