Ion selective PVC membrane electrodes for the determination of trazodone hydrochloride in pharmaceutical formulation

The electrochemical response characteristics of poly(vinyl)chloride (PVC) based membrane electrodes for determination of trazodone hydrochloride (TZH) is described. The membranes of these electrodes consist of trazodone-phosphomolybdate (TZH-PMA) ion pair in a PVC matrix with di-butyl phosphate (DBP) or dioctyl pthalate (DOP) as a plasticizers. The influences of membranes composition, response time, pH of the test solution, and foreign ions on the electrodes performance were investigated. The electrodes exhibited mean slopes of calibration graphs of 56.25 and 58.55 mV per decade of trazodone concentration at 25.0 °C for the optimum electrode 6.0% with DBP (electrode I) and 10.0% with DOP (electrode II) plasticizers respectively. The electrodes were successfully applied to the determination of trazodone hydrochloride and its pharmaceutical preparation with good precision and accuracy.