Table 3.

Key characteristics and biomedical Relevance of CS polymer matrix.

Key Characteristics	Brief Description	Ref.
Source	Derived from chitin via alkaline deacetylation	[185]
Key Properties	Biodegradable, biocompatible, mucoadhesive, cationic, non-toxic	[151]
Solubility	Soluble in dilute acidic solutions (pH < 6.5)	[186]
Functional Groups	Primary amine (-NH2), hydroxyl (-OH), acetyl groups	[187]
Biological Activities	Antibacterial, antifungal, antioxidant, hemostatic, immunomodulatory	[188]
Biomedical Functions	Hydrogel backbone, injectable matrix, controlled drug delivery, wound healing	[11]
Common Modifications	Carboxymethylation, quaternization, thiolation, sulfation, PEGylation	[189]
Representative Derivatives	CMCS, TMC, thiolated CS, N-alkylated CS	[190]
Reactive Potential	Form ionic gels, Schiff bases, or crosslinked networks via multiple chemistries	[191]
Applications in CS-SIHs	Drug delivery, gene therapy, regenerative scaffolds, antimicrobial coatings	[192]