Determination of Dissolved Zn(II) and Cd(II) in Estuarine Water by Using a Bismuth Film Microelectrode

A bismuth‐film electrode was employed to quantify Cd(II) and Zn(II) in estuarine water samples by anodic stripping voltammetry. The bismuth film was deposited in situ simultaneously with the analytes onto a carbon fibre disc microelectrode (radius=3 µm). Under the optimised conditions, calibration plots for both metallic ions were obtained in the range from 0.5 to 10.0 nmol L−1 and the limits of detection for Cd(II) and Zn(II) were estimated as 0.03 and 0.8 nmol L−1, respectively. The accuracy of the results supplied by the bismuth film microelectrode (BiFME) was assessed by performing addition‐recovery experiments and by comparing values with those obtained with a certified sample. The usefulness of the methodology was demonstrated by applying the BiFME to measuring the Cd(II) and Zn(II) content in estuarine water.