Chitosan in tissue engineering
A polysaccharide derived from crustacean shells, structurally reminiscent of the body's own glycosaminoglycans.
Chitosan is produced by deacetylating chitin, the material of crustacean shells and fungal cell walls. It has attracted considerable interest as a comprehensive biomaterial in bone tissue engineering owing to its biocompatibility, biodegradability, and structural similarity to glycosaminoglycans — components of the extracellular matrix — which makes it read as familiar to cells.
It is also chemically tractable. Its amino groups provide handles for functionalisation, so chitosan scaffolds are readily loaded with growth factors. Systematic reviews report that the density and quality of newly formed bone are consistently enhanced when growth factors are incorporated into chitosan scaffolds, with dual systems such as PDGF-BB combined with BMP-6 showing synergistic effects on mineralisation and osteocalcin expression — a result that connects PDGF and the BMP family.
Its weakness is mechanical: chitosan alone is not strong enough for load-bearing bone, so it is typically used in composites with ceramics.
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