Coordination driven nanoscale interfaces in electrochemical heavy metal ions sensing

The widespread industrial, agricultural, and biomedical utilization of heavy metal ions (HMIs) has accelerated their release into aquatic environments, posing severe threats to human health and ecological systems. To mitigate these risks, rapid and efficient environmental monitoring is imperative. Among emerging platforms, electrochemical microsystems offer a compelling architecture for the on-site quantification of HMIs in complex water matrices due to their compact instrumentation, cost-effectiveness, and operational simplicity. Central to these technological advancements is the strategic engineering of coordination chemistry at the sensing interface. Integrating advanced nanomaterials and hybrid composites yields tailored, chelation-driven interfaces rich in specific ligand functional groups. By acting as selective chelating agents, these groups optimize host-guest complexation kinetics, minimize charge-transfer resistance, and enhance thermodynamic stability with target metal ions. These molecular-level binding mechanisms collectively boost analytical sensitivity, selectivity, and long-term sensor stability. This review comprehensively examines recent breakthroughs in electrochemical microsystems for HMI analysis, with particular emphasis on the role of interfacial interactions between HMIs and advanced functional materials in determining sensing performance. Finally, we discuss current technological bottlenecks and outline future strategies for translating these microsystems from laboratory prototypes to practical field applications.