Electrochemical Sensor for the Selective Determination of Prindopril Based on Phosphotunges tic Acid Plastic Membrane

A novel PVC membrane sensor for perindopril based on perindopril-phosphotungstate ion pair complex was prepared. The influence of membrane composition (i.e. percent of PVC, plasticizer, ion-pair complex, and kind of plasticizer), inner solution, pH of test solution and foreign cations on the electrode performance was investigated. The optimized membrane demonstrates Nemstian response (30.9 +/- 1.0 mV per decade) for perindopril cations over a wide linear range from 9.0 x 10(-7) to 1 x 10(-2) M at 25 degrees C. The potentiometric response is independent of the pH in the range of 4.0-9.5. The proposed sensor has the advantages of easy preparation, fast response time. The selectivity coefficients indicate excellent selectivity for perindopril over many common cations (e.g., Na+, K+, Mg2+, Cu2+, Ni2+, rhamnose, maltose, glycine and benzamide. The practical applications of this electrode was demonstrated by measuring the concentrations of perindopril in pure solutions and pharmaceutical preparations with satisfactory results.