Colorimetric and fluorescent AuNM nanosensors for mercury ion detection

Abstract

Mercury ions pose a serious risk to environmental stability and human well-being, emerging as a pressing concern within global public health. Consequently, there is a pressing need to devise cost-effective methodologies for precisely detecting and quantifying residual Hg²⁺ levels in aqueous solutions, thereby mitigating potential hazards. Gold nanomaterials (AuNMs)-based nanosensors have garnered considerable attention as a forefront technology in this pursuit, offering a myriad of advantages for the discernment and quantification of Hg²⁺, including simplicity, rapidity, sensitivity, selectivity, efficiency, and real-time monitoring. In the review, we aim to encapsulate recent advancements in utilizing AuNMs for detecting Hg²⁺ by colorimetry and fluorescence, providing a comprehensive survey of their applications. Central to the discussion are three distinct sensing mechanisms elucidated for Hg²⁺, encompassing the Au/Hg amalgam formed, the T-Hg²⁺-T structures created, Hg²⁺ coordinated with functional groups (–COOH, –OH, –SH, CO, –NH₂) to decorate the surface of AuNMs. The insights furnish a pivotal foundation for developing sensitive, selective, and highly efficient AuNMs-based nanosensors tailored for Hg²⁺ detection, thereby fortifying our defenses against the pernicious effects of heavy metal contamination.