All-Solid-State PVC Membrane Isoniazid-Selective Potentiometric Sensor

In this study; a potentiometric ion-selective electrode (ISE) was developed for the determination of isoniazid. Isoniazid-Tetraphenylborate ion-pair was synthesized and the synthesized ion pair was used as ionophore substance in electrode membrane structures. For the membrane optimization, PVC membrane ion selective electrodes in different compositions were produced by using the synthesized ion pair and their potentiometric performance characteristics were investigated. It was determined that the electrode membrane with the ratio of 3% izoniazid-tetraphenylborate ion pair, 67% nitrophenyloctylether and 30% PVC performed the best potentiometric performance characteristics. For this electrode, linear range, slope, detection limit, pH working range and response time were determined as 5.0×10-6-1.0×10-2 M, 41.2 mV/decade, 2.0×10-6 M, 1-4 and ? 30 s, respectively. By using the proposed electrode, isoniazid contents of the two different drug tablets, which is used in the treatment of tuberculosis, were determined. It was seen that the results obtained by the potentiometric technique were in good agreement with those of the results obtained by UV technique at 95% confidence level