Ion-selective electrode for the determination of trazodone in tablets

Abstract

A coated wire trazodone-selective electrode based on incorporation of trazodone–tetraphenylborate ion pair in a poly(vinylchloride) coating membrane was constructed. The influences of membrane composition, temperature, pH of the test solution, and foreign ions on the electrode performance were investigated. The electrode showed a Nernstian response over a trazodone concentration range from 1.41 × 10^–5 to 0.89 × 10^–2 M, at 25 °C, and was found to be very selective, precise, and usable within the pH range 2.4–9.0. The standard electrode potentials, E°, were determined at 20, 25, 30, 35, 40 and 45 °C and used to calculate the isothermal temperature coefficient (dE°/dT) of the electrode. Temperatures higher than 45 °C seriously affected the electrode performance. The electrode was successfully used for potentiometric determination of trazodone hydrochloride both in pure solutions and in pharmaceutical preparations.