Chitosan coated magnetite nanoparticle as a working electrode for determination of Cr(VI) using square wave adsorptive cathodic stripping voltammetry

Abstract

The application of chitosan coated magnetite nanoparticle modified carbon paste electrode as a working electrode (chitosan@Fe3O4/CPE) for Cr(VI) analysis is presented. The electrochemical detection mode of square wave adsorptive cathodic stripping voltammetry (SWAdCSV) was selected for determination of Cr(VI) due to the high sensitivity and selectivity. The optimal conditions for electrode preparation and the electrode behavior including parameters affecting the SWAdCSV signal were investigated. Two linear ranges of Cr(VI) determination were observed 0.01–0.3 μg L−1 and 0.5–30 μg L−1 with limits of detection of 0.0061 and 0.078 μg L−1, respectively. The precision of the electrode output in terms of %RSD was 11.4% (n = 30). The method was successfully applied to determine Cr(VI) in drinking water and sea water samples with recovery percentages in range 87–110%. Moreover, the results obtained agree with a paired t-test at the 95% confidence level which were comparable to the standard UV–visible spectrophotometric method.