novel potentiometric sensors for pyrilamine maleate

The fabrication and electrochemical response characteristics of four novel potentiometric sensors for determination of pyrilamine maleate (pyrah) were described. the sensors include polymeric membrane electrodes (pme1, pme2) and carbon paste electrodes (cpe1, cpe2). the fabricated sensors were based on the ion-pair of pyrilamine with sodium tetraphenylborate (natpb) and ammonium reineckate (nh4rn) using dibutyl phthalate (dbp) as plasticizing solvent. the sensors showed linear, stable and near-nernstian slopes of 56.4 ± 0.4, 54.2 ± 0.2, 58.8 ± 0.3 and 57.9 ± 0.4 mv decade−1 at 25 ± 0.1 °c and detection limits of 2.0 × 10−5, 1.8 × 10−5, 1.0 × 10−5 and 9.5 × 10−6 mol l−1 for pme1, pme2, cpe1 and cpe2 sensors, respectively. the response time was less than 10 and 8 s for polymeric membrane and carbon paste sensors. the proposed sensors displayed good selectivity for pyrilamine with respect to a number of common inorganic and organic species. the thermal temperature coefficients of the investigated sensors were 0.9508, 0.7012, 0.9450 and 0.6497 mv °c−1. modified carbon paste sensors showed lower detection limits, higher thermal stability and faster response time than those of polymeric membrane sensors. the proposed sensors displayed useful analytical characteristics for determination of pyrilamine in pharmaceutical preparation and biological fluids (human urine and plasma).