Photo-crosslinked glucose-sensitive hydrogels based on methacrylate modified dextran–concanavalin A and PEG dimethacrylate

A series of glucose-sensitive hydrogels based on glycidyl methacrylate modified dextran (Dex-G), ethylene glycol acrylate methacrylate modified concanavalin A (Con A–E) and poly (ethylene glycol) dimethacrylate (PEGDMA) were synthesized by photopolymerization. The Dex-G precursor was prepared through ring-opening reaction, while Con A–E was obtained from Michael addition reaction. FT-IR was used to characterize the structures of pre-polymers and hydrogels. The degree of substitution (DS) of Dex-G was confirmed by 1H NMR and the activity of modified Con A was approved by fluorescence spectroscopy. Swelling test, component loss measurement and SEM observation demonstrated that the size of hydrogels changed differently in the medium of different glucose concentrations and the glucose sensitivity was influenced by the content of component, especially PEGDMA. SEM image also displayed that hydrogels had microporous structures. All the results indicated that the hydrogels had glucose-sensitive property and good biocompatibility, which could be prospectively applied as glucose biosensor and intelligent insulin delivery carrier.