Green Approaches Based on Biodegradable Polymers for Sustainable Electrochemical Sensors

Electrochemical sensors have become integral components of modern analytical science owing to their exceptional sensitivity, rapid analytical performance, portability, and low operating costs. These advantages have facilitated their broad implementation in environmental monitoring, clinical diagnostics, food safety, and pharmaceutical analysis. However, the increasing use of non-biodegradable materials in sensor fabrication has raised concerns regarding electronic waste and environmental sustainability. This review examines the recent progress in the development of green electrochemical sensors based on biodegradable polymers, with a particular focus on cellulose, chitosan, alginate, and starch. The chemical structures, physicochemical properties, and functional characteristics of these biopolymers are discussed in relation to their roles as sensing matrices and electrode modification materials. Representative applications reported in the literature are systematically reviewed, highlighting their use in the detection of pharmaceuticals, biomolecules, pathogens, heavy metals, pesticides, and environmental pollutants through various analytical techniques, including differential pulse voltammetry, square wave voltammetry, amperometry, electrochemical impedance spectroscopy, fluorescence, and colorimetric methods. The integration of biodegradable polymers with nanomaterials is also evaluated in terms of improving sensor sensitivity, selectivity, and stability. The incorporation of biodegradable polymers into electrochemical sensing platforms offers a sustainable pathway toward next-generation analytical technologies. By balancing high sensing efficiency with a lower environmental footprint, these materials support the transition toward analytical systems designed in accordance with the principles of green chemistry and green analytical chemistry.