Simultaneous electrochemical detection of heavy metal ions using a sol–gel synthesized BiVO4 nanosphere modified electrode and its antimicrobial activity

Abstract

This study explores the development of an advanced electrochemical sensor designed for the simultaneous detection of Cd²⁺, Pb²⁺, Cu²⁺, and Hg²⁺ ions. The sensor utilizes sol–gel-synthesized bismuth vanadate (BiVO₄) nanospheres, which are integrated onto a glassy carbon electrode (GCE), and employs square wave anodic stripping voltammetry (SWASV) for electrochemical determination of heavy metal ions. The as-prepared sensor demonstrated exceptional analytical performance and offered a wide linear detection range from 0 μM to 110 μM, along with low detection limits of 2.75 μM for Cd²⁺, 2.32 μM for Pb²⁺, 2.72 μM for Cu²⁺, and 1.20 μM for Hg²⁺ ions. These characteristics made the sensor highly suitable for precise monitoring of heavy metal contamination in both environmental and industrial samples. Beyond their sensing capabilities, the BiVO₄ nanospheres also exhibited significant antimicrobial activity against bacterial strains such as E. coli and S. aureus, as well as fungal strains like C. albicans and C. parapsilosis. This antimicrobial effect was attributed to the enhanced surface reactivity and the generation of reactive oxygen species (ROS), which disrupt microbial cellular functions. This dual-functional approach highlighted the substantial progress in both electrochemical sensing and antimicrobial applications. This research presents a strong platform for tackling urgent challenges in environmental monitoring and microbial control.