Characteristic of Membrane Sensors for the Selective Determination of Some Anti-histaminic Pharmaceutical Formulations

The construction and general performance characteristics of potentiometric sensors responsive to some anti-histaminics Hydroxyzine hydrochloride (HYZ), Meclozine hydrochloride (MOZ) were described. The membranes incorporate the ion-association complex of the drugs with Sodium 12-Tungstophosphate (TP) sensor-1, Ammonium Reineckate (AR) senser-2, and Ammonium Molbydate(AM) senser-3as electroactive materials. These sensors exhibit fast, stable, and near-Nernstain response over the concentration range 10-2 to 10-7 M with slopes of 53.07 and 52.14 mV per concentration decade for sensors 1, 2. No interferences are caused by many inorganic and organic cations. The sensors have a fast response time (20-40 s) and applicaple over a wide range of pH 2-7), low detection limit (1.8×10-7 M) and good stability (5-6 weeks).The sensors were used for direct potentiometric of anti-histaminics in some pharmaceutical preparations. Validation of the method according to the quality assurance standards shows suitability of the proposed sensors for use in the quality assurance of these drugs. Results with a recovery of 99.5 % and a mean standard deviations of ±1.3 % of the nominal are obtained which compared fairly well with data obtained using the British pharmacopoeia method.