Four armed polyethylene glycol (T-PEG) was modified with DOPA and disulfide bonds at the chain end to afford the gelator of PEG-DOPA. PEG-DOPA could form hydrogel rapidly with sodium periodate (NalO

4

) in the system. It was found that the hydrogel degraded in the presence of glutathione solution (GSH)

and the degradation time could be adjusted by using different concentrations of GSH. The mechanical strength was obviously enhanced with DOPA in the structure of gelator

and the mechanical modulus of hydrogels increased with increasing the concentration of PEG-DOPA. BMSCs cells were cultured in the hydrogels that showed no cytotoxicity.