Cathodic stripping voltammetric determination of arsenic in sugarcane brandy at a modified carbon nanotube paste electrode

Abstract

We have developed an eletroanalytical method that employs Cu2+ solutions to determine arsenic in sugarcane brandy using an electrode consisting of carbon paste modified with carbon nanotubes (CNTPE) and polymeric resins. We used linear sweep (LSV) and differential-pulse (DPV) voltammetry with cathodic stripping for CNTPE containing mineral oil or silicone as binder. The analytical curves were linear from 30 to 110 μg L−1 and from 10 to 110 μg L−1 for LSV and DPV, respectively. The limits of detection (L.O.D.) and quantification (L.O.Q.) of CNTPE were 10.3 and 34.5 μg L−1 for mineral oil and 3.4 and 11.2 μg L−1 for silicone. We applied this method to determine arsenic in five commercial sugarcane brandy samples. The results agreed well with those obtained by hydride generation combined with atomic absorption spectrometry (HG AAS).