A series of water-soluble biodegradable oligo(lactide-co-acryloyl carbonate)-b-poly(ethylene glycol)-b-oligo(lactide-co-acryloyl carbonate) (OLAC-PEG-OLAC) triblock copolymers were synthesized by ring-opening copolymerization of lactide (LA) and acryloyl cyclic carbonate (AC) and applied for in situ formation of novel bioactive biodegradable hydrogels via photo-crosslinking.The rheology measurements showed that gelation times (0.8~8 min) and storage moduli (170~10000 Pa) of hydrogels could be controlled by AC content

polymer concentration and photo-initiator concentration.The results of degradation tests displayed that degradation rates of these hydrogels could be tailored by AC and LA contents.Notably

the multiple acryloyl functional groups in OLAC-PEG-OLAC copolymers allowed direct conjugation of thiol-containing biomolecules like RGD peptides via Michael addition reaction prior to gelation

which provides a facile access to injectable bioactive biodegradable hydrogels.The preliminary cell experiments demonstrated that RGD peptide modified hydrogels could well support adhesion and growth of MG63 osteoblast cells.These rapidly photo-crosslinkable biodegradable hydrogels with controlled mechanical properties

tailored biodegradation rates

and versatile bio-functionalization form an excellent basis for the development of advanced bioactive tissue engineering scaffolds.