In situ Bi/carboxyphenyl-modified glassy carbon electrode as a sensor platform for detection of Cd2+ and Pb2+ using square wave anodic stripping voltammetry

Herein, a sensor platform, Bi/carboxyphenyl-modified glassy carbon electrode (Bi/CP/GCE), is presented for the detection of Cd2+ and Pb2+ using square wave anodic stripping voltammetry (SWASV). The sensor was obtained through electrografting of the GCE using 4-carboxybenzene diazoniu m tetrafluoroborate (4-CBD) and in situ electrodeposition of Bi3+. The stability of the grafted layer and the proposed mechanism of interaction between the metal ions and the grafted layer is supported by DFT calculations. Under the optimized conditions , Pb2+ had a linear working range of 25-500 mu g(-1) with LOD of 10 mu g L-1 (S/N = 3) and Cd2+ provided linear range of 50-500 mu g L-1 and LOD of 25 mu g L-1. The fabricated electrode presented good repeatability and reproducibility. The applicability of the electrode was tested for determination of Cd2+ and Pb2+ in tap water resulting in re-coveries of 96.2-101% for Cd2+ and 98.1-104% for Pb2+.

Automated summary

The newly developed Bi/CP/GCE sensor showed good linear working range and detection limits for heavy metal ions Cd2+ and Pb2+, as well as good repeatability and reproducibility. The applicability of the electrode was validated through the detection of Cd2+ and Pb2+ in tap water.