Selectivity of electrodes based on heptyl ether <i>n</i>-trifluoroacetyl benzoic acid to tetrazole anions and its 5-monosubstituted derivatives
The influence of the plasticizer nature on the selectivity of electrodes based on neutral carrier - heptyl 4-trifluoroacetylbenzoate - to tetrazole anions and its 5-monosubstituted derivatives is investigated. It is shown that the selectivity of the electrodes increases towards tetrazole ions against perchlorate conforming to the decrease of plasticizer basicity in the series dibutyl adipinate > bis(2-ethylhexy) sebacate > dibutyl phthalate > 2-nitrophenyl octyl ether which is explained by competitive interaction between plasticizer (donor) and neutral carrier (acceptor). Correlations have been found, namely selectivity of tetrazolate-selective electrodes caused by the introduction of the neutral carrier into the membrane improves with the increase of the electron donor ability of the substituents in the tetrazole ring, and selectivity coefficients of electrodes towards tetrazole anions against perchlorate are proportional to distribution constants of those tetrazolates in n -octanol-water system.