Box-Behnken response surface design for the optimization of electrochemical detection of cadmium by Square Wave Anodic Stripping Voltammetry on bismuth film/glassy carbon electrode

In this paper, a Box-Behnken design (BBD) was conducted and the response surface methodology (RSM) was employed to investigate the influence to different parameters to Cd(II) detection at bismuth film/glassy carbon electrode (Bi/GCE) by Square Wave Anodic Stripping Voltammetry (SWASV), and the stripping peak current was used to evaluate the detection performance of each parameter combination. A three-level-three-factor full factorial (33) BBD has been conducted to investigate interaction effects. The relationship between stripping peak current and the three factors was quantitatively described by a multivariate regression model through the RSM. The optimal parameter combination within the studied experimental range was obtained to improve the detection performance, considering the interaction effects among Bi(III) concentration, pH and deposition potential. Under the optimal parameter combination, SWASV was applied to detect the concentration of Cd(II) on Bi/GCE, the linear calibration curve ranged from 1 to 170 μg/L with a detection limit of 0.3 μg/L (S/N = 3). The proposed analytical procedure was further applied to detect trace Cd(II) in soil samples with satisfactory results.