The Complex (2,3;6,7;10,11;14,15-Tetraphenyl-4,9,13,16- Tetraoxo-1,5,8,12-Tetraazacyclohexadecane) Copper(II) as a Carrier for a Salicylate-Sensitive Poly(vinylchloride) Membrane Electrode

Abstract

A new salicylate-selective electrode based on the complex (2,3;6,7;10,11;14,15-tetraphenyl- 4,9,13,16-tetraoxo-1,5,8,12-tetraazacyclohexadecane) copper(II) [CuL] as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of –60.9 ± 1.0 mV/decade and a linear range from 1.0 × 10 –6 to 1.0 × 10 –1 M for salicylate. The detection limit is 5.0 × 10 –7 M. The electrode has a fast response time (5–15 s) and can be used for more than three months. The selective coefficients were determined by the fixed interference method (FIM) and separate solution method (SSM). The salicylate-selective electrode could be used in the pH range 3.5–10.5. It was employed as an indicator electrode for direct determination of salicylate in pharmaceutical samples.