Studies On The Characteristics Of Three Novel PVC Membrane Quaternary Ammonium Cation Selective Electrodes Based On Calix [4] Arene Derivatives

The response characteristics of three novel PVC membrane ion-selective electrodes based on 5,11,17,23- tetra- ten- butyl- 25,26,27,28- tetrakis [3-(methoxycarbonyl) benzyloxy] calix[4] arene ( I ) and 5,11,17,23- tetra- tert- butyl-25,26,27,28- tetrakis [3- (ethoxycarbonyl) benzyloxy] calix[4] arene ( II ) and25,26,27,28- tetrakis [3- (methoxycarbonyl) benzyloxy] calix[4] arene ( III ) as carriers were investigated. The electrodes exhibit almost Nernst response characteristics for Bu4N+, Et4N+ and Me4N+. The linear response ranges of the electrode based on ( I) towards Bii4N+, Et4N+ and Me4N+ are 10-6-10-1,10-6~10-1, 10-4~10-1 mol/ L and the corresponding slopes are 59.2,55.0 and 55.9 mV/ pc with correlation coefficients of 0.9999, 0.9993 and 0.9999, respectively; the linear response ranges of electrode based on ( II ) towards Bu4N4, Et4N+ and Me4N+ are 10-6~10-1, 10-5-10-1,10-4~10-1 mol/ L and the corresponding slopes are 59.8,56.6 and 56.0 mV/ pc with correlation coefficients of 0.9996, 0.9999 and 0.9999, respectively; the linear response ranges of electrode based on (III ) towards Bu4N+, Et,N+ and Me4N+ are lO^lO'1,10'6~10'', lO^-lO'1 mol/ L and the corresponding slopes are 58.1,54.6 and 55.5 mV/ pc with correlation coefficients of 0.9999, 0.9996 and 0.9999, respectively. The electrodes have advantages of stability, repeatability and wider pH range. The electrodes were applied to the content assay of propantheline bromide tablets. The results obtained are in agreement with that determined by the pharmacopoeia method.