Figure 5.

Dynamic biomaterials with tunable biochemical cues. (A) Hydrogels can present dynamic biological cues by removal and addition of bioactive molecules. Photochemistry allows spatiotemporal removal and sequential presentation of biochemical cues for 2D and 3D environment of hydrogels. (B) Reactions commonly used to conjugate biomolecules to biomaterials include thiol-ene, Michael-type, azide-alkyne, and oxime ligations. Dynamic regulation of biochemical cues within 3D hydrogels enable (C) creation of complex multicellular 3D structures and (D) spatiotemporal regulation of stem cell differentiation. Scale bar, 100 μm. (Panel C created from data in DeForest and Anseth 2011. Panel D created from data in DeForest and Tirrell 2015.)