The Use of Ultrasound for the Analytical Determination of Nitrite on Diamond Electrodes by Square Wave Voltammetry

Abstract

This work describes an analytical methodology for the determination of nitrite ions in aqueous solutions using boron‐doped diamond electrodes and square wave voltammetry associated with ultrasound radiation. The nitrite ions were oxidized to nitrate ions in Britton‐Robinson buffer solutions 0.1 M, pH 2.0 at 1.0 V versus Ag/AgCl. The voltammetric response of nitrite in the presence of ultrasound showed a peak current five times higher than the obtained in silent conditions. Thus, the detection limit obtained in the presence of radiation was 17 nM (0.782 µg l⁻¹), a small value if compared with that obtained in the absence of ultrasound: 140 nM (6.44 µg l⁻¹).

Keywords:

• Nitrite ions
• diamond electrode
• square wave voltammetry
• sonoelectroanalysis

The authors thank CNPq (Proc. 142930/2005‐9) and Fapesp (Procs. 06/50692‐2 and 05/50649‐7) of Brazil, for the scholarships and financial support to this work.