The growing concern over heavy metal contamination in environmental and industrial settings has intensified the need for sensitive, selective, and cost-effective detection technologies. Electrochemical sensors, due to their high sensitivity, rapid response, and portability, have emerged as promising tools for detecting heavy metals. Recent years have seen significant progress in utilizing biopolymer-based materials to enhance the performance of these sensors. Biopolymers, derived from renewable raw materials, have garnered considerable interest in both science and industry. These biopolymer-based composites are increasingly recognized as superior alternatives to conventional non-biodegradable materials because of their ability to degrade through environmental exposure. This review provides a comprehensive overview of recent advancements in biopolymer-based electrochemical sensors for heavy metal detection. It discusses various types of biopolymers and bio-sourced polymers, their extraction methods, and chemical properties. Additionally, it highlights the state of the art in applying biopolymers to electrochemical sensor development for heavy metal detection, synthesizing recent advances and offering insights into design principles, fabrication strategies, and analytical performance. This review underscores the potential of biopolymer-based sensors as cost-effective, eco-friendly, and efficient tools for addressing the pressing issue of heavy metal contamination in water and discusses their advantages and limitations. It also outlines future research directions to further enhance the performance and applicability of these sensors.

The growing concern over heavy metal contamination in environmental and industrial settings has intensified the need for sensitive, selective, and cost-effective detection technologies. Electrochemical sensors, due to their high sensitivity, rapid response, and portability, have emerged as promising tools for detecting heavy metals. Recent years have seen significant progress in utilizing biopolymer-based materials to enhance the performance of these sensors. Biopolymers, derived from renewable raw materials, have garnered considerable interest in both science and industry. These biopolymer-based composites are increasingly recognized as superior alternatives to conventional non-biodegradable materials because of their ability to degrade through environmental exposure. This review provides a comprehensive overview of recent advancements in biopolymer-based electrochemical sensors for heavy metal detection. It discusses various types of biopolymers and bio-sourced polymers, their extraction methods, and chemical properties. Additionally, it highlights the state-of-the-art in applying biopolymers to electrochemical sensor development for heavy metal detection, synthesizing recent advances and offering insights into design principles, fabrication strategies, and analytical performance. The review underscores the potential of biopolymer-based sensors as cost-effective, eco-friendly, and efficient tools for addressing the pressing issue of heavy metal contamination in water and discusses their advantages and limitation. It also outlines future research directions to further enhance the performance and applicability of these sensors.

A screen-printed carbon electrode SPCE was modified by the incorporation of polypyrrole (Ppy), as a conductive polymeric matrix and hemicellulose extract from Cactus as a hydrophilic biopolymer. This polypyrrole-hemicellulose composite film (Ppy-HEM@SPCE) was designed for the selective and sensitive detection of Pb(II) trace in aqueous media by square wave anodic stripping voltammetry (SWASV). The porous structure of the Ppy film immobilized hemicellulose homogeneously, providing an even distribution of hydroxyl and carboxyl groups throughout the coating. These functional groups allowed the coordination of Pb(II) ions. The Ppy-HEM@SPCE composite film was characterized by different electrochemical and physicochemical techniques revealing the efficient association and improved coordination properties. Under optimized conditions, a linear relationship was obtained between the redox current and metal ion concentrations ranging from 1 pM to 1 μM and a detection limit of 1 pM was determined. The Ppy-HEM@SPCE composite film demonstrated excellent repeatability, reproducibility as well as long-term stability and potential of regeneration. In addition, the detection of Pb(II) was successfully performed in various real water samples as demonstrated by comparison with ICP/MS as a classical detection method.