From:  Injectable biodegradable hydrogels for in situ tissue engineering

 Comparison of natural and synthetic polymers for injectable hydrogels.

Polymer typeExamplesAdvantagesLimitationsKey applications
Natural polymers ※Collagen, HA, chitosan, alginate, gelatinBiocompatibility, bioactive signaling, cell adhesionBatch variability, immunogenicity risk, and limited mechanical strengthCartilage, bone, wound healing
Synthetic polymersPEG, PLGA, PCLTunable properties, reproducibility, and low immunogenicityLack of bioactivity, slow degradation in some casesBone, neural, cardiac
Hybrid/CompositePEG-collagen, GelMACombines bioactivity with mechanical tunabilityComplex synthesisSoft tissue, cartilage, skin

※ Collagen and hyaluronic acid are the most commonly studied natural polymers to use as injectable hydrogels because of their natural ECM components and biological signaling properties.