Novel potentiometric sensors for the selective determination of domperidone

Abstract

The fabrication and electrochemical response characteristics of two novel potentiometric sensors for the selective determination of domperidone (DOM) are described. The two fabricated sensors incorporate DOM–PTA (phosphotungstic acid) ion pair as the electroactive material. The sensors include a PVC membrane sensor and a carbon paste sensor. The sensors showed a linear, stable, and near Nernstian slope of 56.5 and 57.8 mV/decade for PVC membrane and carbon paste sensors, respectively over a relatively wide range of DOM concentration (1.0 × 10⁻¹–1.0 × 10⁻⁵ and 1.0 × 10⁻¹–3.55 × 10⁻⁶ M). The response time of DOM–PTA membrane sensor was less than 25 s and that in the case of carbon paste sensor was less than 20 s. A useful pH range of 4–6 was obtained for both types of sensors. A detection limit of 7.36 × 10⁻⁵ M was obtained for PVC membrane sensor and 1.0 × 10⁻⁶ M was obtained for carbon paste sensor. The proposed sensors showed very good selectivity to DOM in the presence of a large number of other interfering ions. The analytical application of the developed sensors in the determination of the drug in pharmaceutical formulations such as tablets was investigated. The results obtained are in good agreement with the values obtained by the standard method. The sensors were also applied for the determination of DOM in real samples such as urine by the standard addition method.