Integrating Green Chemistry Principles into the Fabrication of MIP Electrochemical Sensors for Heavy Metal Monitoring

Heavy metal contamination remains a critical global environmental issue due to the persistence, bioaccumulation, and toxicity of metal ions such as Pb²⁺, Cd²⁺, Hg²⁺, and As³⁺. Although conventional analytical techniques provide high sensitivity and accuracy, they often rely on energy-intensive instrumentation, hazardous reagents, and generate considerable chemical waste, raising concerns regarding their environmental sustainability. In this context, molecularly imprinted polymer (MIP)-based electrochemical sensors have emerged as promising alternatives, offering high selectivity, operational simplicity, and compatibility with miniaturized and in situ analysis. This review critically examines the integration of Green Analytical Chemistry (GAC) principles into the design and fabrication of MIP-based electrochemical sensors for heavy metal monitoring. Particular attention is given to material selection, polymerization strategies, template removal approaches, and electrode modification techniques, with emphasis on their environmental implications. The applicability of quantitative greenness assessment tools, including the Analytical Eco-Scale, GAPI, AGREE, and AGREEMIP, is discussed in the context of sensor development workflows, highlighting both their strengths and current limitations in addressing fabrication stages, nanomaterial synthesis, and end-of-life considerations. By identifying methodological bottlenecks, particularly solvent-intensive template removal and limited reusability, this review outlines practical directions for advancing more sustainable sensor platforms. Overall, the work provides a critical framework for aligning analytical performance with environmental responsibility in next-generation MIP-based electrochemical sensing systems.