Fabrication of a MXene-based shape-memory hydrogel and its application in the wound repair of skin

Wound dressings can generally complete hemostasis and provide temporary protection after skin damage. Herein, a MXene-based hydrogel was prepared from MXene, gelatin, poly(ethylene glycol)diacrylate (PEGDA) and N,N'-methylenebis(acrylamide) (HEAA) to prepare wound-dressing hydrogels for skin repair. HEAA and PEGDA crosslink polymerization formed the first layer of the network. Hydrogen bonds between MXene, PHEAA, and gelatin formed the second layer of the network. To make the hydrogel more suitable for skin repair, the mechanical properties of the hybrid hydrogel were adjusted. The MXene-based hydrogel could recover its original shape in 16 s upon immersion in water or for a few minutes under light irradiation. The obtained hydrogel showed good photothermal properties upon light irradiation (808 nm, 1 W cm^-2) for 20 s, and its temperature on the surface could reach 86.4 °C. Due to its good photothermal properties, this MXene-based hydrogel was suitable for skin repair.