Gelatine methacrylamide-based multifunctional bilayer hydrogels for accelerating diabetic wound repair

Diabetic wounds are a common disease that plague many doctors in the clinic. Diabetic wounds are caused by increased blood sugar levels, which leads to microvascular disease and skin dystrophy. Additionally, their occurrence can be accompanied by inflammation and a variety of bacterial infections. Diabetic wounds are complex; therefore, achieving good results after a single treatment modality is often difficult. In this study, we used materials science engineering methods to integrate several factors required for diabetic wound treatment, which resulted in the development of a bilayer hydrogel. First, the upper layer of the hydrogel inhibits bacterial growth and promotes wound closing, which solves the problems of wound infection and protection. Additionally, the lower layer of the hydrogel has a porous structure, which promotes the adhesion and growth of wound healing-related cells. Moreover, the lower layer of the hydrogel can release cytokines that promote vascular endothelial cell and fibroblast migration and stimulate skin tissue regeneration. We evaluated the ability of this double-layer hydrogel to heal diabetic wounds in vivo and in vitro and found that it offered protection while promoting healing. We also determined that a combination of multiple factors can provide better reparative effects to treat chronic diabetic wounds.