Potentiometric determination of urinary iodide using a nanoparticle modified carbon paste electrode

Abstract

A simple and sensitive solid carbon paste electrode (CPE) based on the nanoparticles of silver iodide and silver sulfide was prepared for potentiometric determination of iodide in urine samples. The results indicated that the provided CPE exhibited a wide linear range (8.0 × 10⁻⁹ to 1.0 × 10⁻³ mol L⁻¹), low detection limit (7.0 × 10⁻⁹ mol L⁻¹), near Nernstian sensitivity (55.3 mV per decade) and short response time (<60 s) to iodide. The provided CPE was successfully applied for the determination of iodide in human urine samples with good stability and repeatability.