A comprehensive review of chitin/chitosan-derived antimicrobial materials: Structural design, structure-activity...

This review covers the preparation strategies of chitin/chitosan derivatives and their impact on material properties, the peptide-coupling chemistries and their synergistic roles in constructing chitosan-antimicrobial peptide systems, and the development of metal/inorganic, organic and natural extract-based composites with enhanced physical, chemical and biological properties. To clarify these diverse material systems, this review systematically discusses a variety of antibacterial pathways, including membrane destruction, reactive oxygen species (ROS) generation, metal-ion release and chelation-induced ionic imbalance, metabolic inhibition and gene expression interference. Different from previous reviews that mainly focused on a single material type, antimicrobial mechanism or application field, this review highlights the relationships among structural design, antimicrobial mechanisms and application-specific suitability. Herein, we summarize the key challenges and future opportunities, with a focus on scalable production, elucidation of structure-activity relationships, and application-oriented material design. The review covers: i) derivatization strategies of chitin/chitosan materials and the effects on properties; ii) design and functional principles of chitosan-antimicrobial peptide conjugates; iii) integrating antimicrobial mechanisms across different chitin/chitosan materials; iv) representative applications in food, biomedicine, and environmental remediation. This review aims to provide design guidance for next-generation chitin/chitosan-derived antimicrobial materials.