Potentiometric Membrane Sensors for the Selective Determination of Memantine Hydrochloride in Pharmaceutical Preparations

Abstract

Three potentiometric sensors responsive to Memantine HCl (MEM) drug are described, characterized, compared and used for drug assessment. The sensors are based on the use of the ion-association complex of (MEM) cation with Flavianate (FA), 5-Nitro-barbiturate (NBA) and phosphomolybdate (PMA) anions as electroactive materials in plasticized poly(vinyl chloride) membranes. The sensors demonstrate fast near-Nernstian response for MEM with lower limits of quantification of: 4.76x10-6, 5.22x10-5 and 9.08x10-6 M with detection limits of 1.74x10-6, 9.17x10-6 and 2.93 x10-6 M , with slopes of 55.45, 45.84 and 54.58 mV/concentration decade over a pH range of 2.66-9.54, 4.64-8.51 and 4.60-9.07 for Flavianate (FA), 5-Nitro-barbiturate (NBA) and phosphomolybdate (PMA), respectively. The three sensors showed good selectivity for MEM drug over several inorganic cations, nitrogeneous excipients and diluents commonly used in drug formulations. The dissolution profile was also plotted using the proposed sensor at optimum electrode conditions.