Comprehensive insights into chitosan hydrogels: from crosslinking and characterization to immunomodulation, microbiome interactions and biomedical uses

Interest in the biomedical field has surged due to the exploration of alternative biomaterials, particularly hydrogels and chitosan-based hydrogels. These materials present distinctive attributes such as compatibility with living systems, natural breakdown in biological environments, and economic efficiency, rendering them highly promising diverse applications. Chitosan, whether in its pure form or in combination with other polymers, has emerged as a key focus due to its potential in biomedical applications. Its immunomodulatory properties are particularly noteworthy, as they contribute to regulating immune responses, which is beneficial for tissue engineering and drug delivery purposes. Chitosan’s biodegradability ensures environmentally friendly degradation post-application, addressing concerns about long-term impact. Additionally, its interaction with the microbiome holds promise for promoting symbiotic relationships with microbial communities, crucial for maintaining homeostasis in biological environments. This comprehensive review delves into the diverse characterization methods and crosslinking techniques utilized in crafting chitosan hydrogels, modification of chitosan while also exploring their medical applications and implications in immunomodulation, biodegradability, and microbiome interaction.