Chitosan-based hydrogels: a general review of their areas of application

Abstract

This review article provides an overview of recent advances in chitosan-based hydrogels, highlighting the motivation for their development in the context of the transition to sustainable polymeric materials and the limitations associated with synthetic polymers. The review integrates the major areas of application of chitosan hydrogels, with a focus on biomedicine and pharmaceuticals (wound dressings, drug delivery platforms, tissue engineering matrices, haemostatic and antimicrobial systems), but also on emerging uses in the food industry (active/smart biodegradable packaging, edible coatings and nutrient delivery systems), agriculture (controlled delivery of nutrients/agrochemicals and soil conditioning), environmental protection (pollutant adsorption, heavy metal sensing, and solar desalination), aquaculture and electronics/bioelectronics (flexible sensors, bioelectronic interfaces, electrolytes and energy storage components). In addition, transdisciplinary applications in forensics (fingerprint visualisation and explosives detection) and aeronautics/aerospace (CO2 capture, lightweight multifunctional materials for electromagnetic/thermal/acoustic protection) are discussed. Overall, the paper highlights the structure-property-function relationship of chitosan hydrogels and outlines research directions for optimising mechanical performance, degradation control and integration into advanced applications.