Scheme 1.
The formation of the BMP-2 tethered hydrogel with MC3T3-E1 cells. Hydrogels were formed from a precursor solution containing 8-arm PEG-norbornene, 8-arm PEG-norbornene-BMP-2, crosslinker (PEG-dithiol or matrix- metalloproteinase (MMP)-sensitive crosslinker), cell adhesion peptide, and MC3T3-E1 cells. The BMP-2 characterization studies utilized hydrogels with the PEG-dithiol crosslinker without cells. Close-up box highlights the crosslinked network. Not drawn to scale.