THE ALL-SOLID-STATE BENZYDAMINE ION-SELECTIVE ELECTRODE AND DIELECTRIC-CONSTANT EFFECT ON THE ELECTRODE LINEARITY SLOPE

All-solid-state benzydamine ion-selective electrode with ion-pair complex of benzydamine with hetero-tungstate as electroactive material showed good response performance, its lower limit of linearity response range is 1.5×10^-6 mol/L with a slope of 58 mV/log C. The electrode can be used for potentiometric determination of benzydamine in blood and urine. Microgram and submicrogram amount of benzydamine can be determined using the proposed single-drop method. For electrodes based on ion-pair complex of benzydamine with hetero-poly acid, the response slope did not decrease significantly with decreasing dielectric constant in the ethanol— water mixed background. However, for electrode based on benzydamine dicyclohexyl-naphthalene sulphonate, dipicrylaminate, tetraphenylborate, tetraiodobismuthate or picrate, the electrode linearity slope decreased continuously with decreasing dielectric constant.