In this work, a potentiometric method was developed for the determination of loperamide hydrochloride in bulk powder and in pharmaceutical preparations by using a paste-carbon electrode modified with an ion-pair complex between loperamide hydrochloride (LOP) and Phosphomolybdic acid (PMA). The optimum conditions for electrode formation were studied, and it showed that the best results for the electrode were using DOP plasticizer with mixing ratios: 46.5%, 46.5% graphitic coal,7.0% ion-pair complex. The pre pared electrode showed a Nernstian response to the determination of loperamide hydrochloride within a linear range of (0. 99 - 183.12μM), a slope of (57.59mV/decade), a correlation coefficient (R^2=0.9995), and a detection limit of (0.306μM). The electrode works within a pH range between (2-7) and a temperature range between (25-60) ºC, and with a response time not exceeding (15 sec). The electrode life was extended up to 60 days without noticeable changes in the latency value. The method was successfully applied to determine loperamide hydrochloride in the purified state with a retrospective range of (98.969-101.767)%, and the RSD% did not exceed the value(1.638%). The method has been successfully applied to determine loperamidehydrochloride in pharmaceutical preparations.
Al-Baath University Journal.
2023.