Abstract
A coated-wire ion selective electrode based on ion-pair complex of citapolarm hydrobromide (CT) with sodium tetraphenyl borate as electroactive material in the presence of dioctylphthalate (DOP) as the plasticizing solvent mediator was prepared. The electrode displays Nernstian response of 56.83 mV/decade over the concentration range of 1.0x10(-6) to 1.0x10(-2) mol/L at 25 degrees C. The influence of membrane composition, pH of the test solution and foreign ions on the electrode were investigated. The electrode was successfully applied to determination of the drug in pure form, urine and plasma by standard addition potentiometry.