Microsphere-structured hydrogel crosslinked by polymerizable protein-based nanospheres

In this work, the vinyl groups were introduced onto gelatin to create methacrylated gelatin nanoparticles (MA-GNP) as crosslinking centers for fabricating macromolecular microsphere composite (MMC) hydrogels. The MA-GNPs with an average size of ~100 nm, measured with dynamic light scattering , were also visualized using AFM . The presence of C C bonds in the nanoparticles was further confirmed with the proton NMR . Then, the MA-GNP was incorporated as a cross-linker to synthesize MMC hydrogels using acrylamide as the monomer . The resulting hydrogels are porous with tunable pore sizes; and exhibit the improved compressive resistance and elasticity. Increasing the dosage of MA-GNP appropriately led to the reduction of the equilibrium swelling ratio but improved thermal stability of the gels. Moreover, the MA-GNP can endow the gels with enhanced biocompatibility. Overall, the novel protein-based nanospheres are of great potential as both nano-crosslinker and reinforcer to create polymer hydrogels with tailored properties.