Internal Solid Contact Electrode for the Determination of Salbutamol Sulfate in Pharmaceutical Formulation

An internal solid contact salbutamol ion-selective sensor was fabricated based on a conducting poly(aniline) film immobilized on a glassy carbon electrode surface and a plasticized poly(vinyl chloride) (PVC) sensing membrane containing an ion-pair complex of salbutamol (SB) with tetraphenylborate. Effects of various conditions for the electropolymerization of aniline, including the conducting support, aniline concentration, solution pH and polymer film thickness were investigated. The sensor showed a Nernstian slope of 60.4mV/decade (25 °C) in the SB concentration range of 1.0×10–1 to 4.0×10–5 M, low detection limit (1.2×10–5 M), and fast response time(15approx30 s). This sensor was successfully applied to the determination of SB in the pharmaceutical preparation which showed 99.1–100.6 % recovery.