Fig. 4: Enzyme-responsive hydrogels for application in generalized inflammation.
From: Enzyme-responsive biomaterials for biomedical applications
a (i) Fabrication scheme of MMP-degradable, peptide-cross-linked alginate hydrogel. Bis-cysteine peptides cross-link with norbornene-modified alginate via thiol-ene chemistry upon UV exposure in the presence of a photoinitiator. Cysteine-conjugated RGD peptides can be co-incorporated, and the cross-linkers can be engineered for enzymatic degradability. (ii) In vivo cell infiltration into enzymatically degradable peptide-cross-linked alginate hydrogels after 8 weeks of subcutaneous implantation. Hydrogels cross-linked with 3 mg/mL degradable or control cross-linkers were stained with Hematoxylin and Eosin. Scale bar = 100 μm. Cell counts were conducted within the total hydrogel area (including both fiber-rich and fiber-free regions) and within fiber-free regions alone. Adapted from Biomaterials, Lueckgen et al.99. b (i) EGCG conjugated hyaluronic acids and tyramine conjugated hyaluronic acids cross-link via tyrosinase catalysis to form tissue adhesives that can be injected in wound areas. (ii) In vitro and in vivo sealing test results of the HA_TE hydrogel compared with commercial cyanoacrylate and fibrin glue. Adapted from Biomaterials, Kim et al.103. Created in BioRender. Pi, P. (2025) https://BioRender.com/oc1tu63.
