Metformin-Embedded Hydrogels: A Promising Approach for Accelerating Healing in Diabetic Ulcers

Difficulty in wound healing is a significant worldwide clinical challenge with serious health consequences and even life-threatening consequences. We designed an acrylic hydrogel loaded with metformin and investigated its mechanism of action in promoting wound repair.

In this study, we obtained self-assembled metformin hydrogels (SAMHs) delivery system using acrylic acid (AA) as matrix and ammonium persulfate (APS) as initiator, and evaluated the appearance, water vapor transmission rate, swelling properties, mechanical properties, and bioactivities of the SAMHs, and finally assessed the potential of the SAMHs for the treatment of chronic wounds in a diabetic rat wound model.

SAMHs were colorless and transparent in appearance, with a water vapor transmission rate of 3530 g·m-2·day-1, a dissolution rate of 504%, a Young's modulus of 34 Kpa, and an elongation at break of 595.7%.The drug loading capacity of SAMHs was 0.8±0.04 mg·g-1 and the cumulative release amounted to 71.67±2.03%. In vivo experiments showed that on day 14, the SAMHs group achieved a wound healing rate of 96.74%, with complete epithelialization, a collagen fiber content of 75.10%, elevated VEGF expression, and a TNF-α level of 162.62 pg·mL⁻¹, all of which exhibited significant differences compared to the control group.

SAMHs exhibit excellent performance in several aspects, achieving slow drug release and promoting wound repair. In addition, SAMHs are simple and low-cost to prepare, which is expected to bring more cost-effective treatment options for diabetic patients. However, antimicrobial properties and clinical trial data are lacking in this study, and their applicability in complex wounds requires further validation.

The hydrogel we prepared has excellent properties, is suitable for use in chronic wounds and promotes wound healing in diabetic rats and is an effective therapeutic strategy for chronic wounds.