Fig. 4

Construction process and the structure of representative glucose-responsive hydrogels. a Diagram of the preparation process of Gel-AFPBA-ins hydrogels to achieve glucose-responsive release of insulin and the process of releasing insulin in a glucose environment. Reproduced with permission [103]. Copyright 2022, Royal Society of Chemistry. b Diagram of the synthesis of a glucose-responsive injectable hydrogel based on GOX with zinc ions, organic ligands, and a small-molecule drug, DFO mesylate. Reproduced with permission [94]. Copyright 2022, American Chemical Society. AFPBA-ins 4-(2-acrylamide ethyl aminoformyl)-3-fluorobenzene boric acid with insulin, DG@Gel glucose-responsive multifunctional metal–organic drug-loaded hydrogel, DFO deferoxamine, GOX glucose oxidase, GelMa gelatin methacrylate, Gel-AFPBA-ins the hydrogel system was composed of GelMa and AFPBA-ins, IDA 4,5-imidazoledicarboxylic acid, UV ultraviolet