Effect of tranexamic acid-functionalized photothermal hydrothermal treated oxidized graphene sponge on diabetic wound healing: Hemostasis, antibacterial, and regeneration

Abstract

In the healing process of chronic diabetic wounds, a prolonged inflammatory phase and an increased number of inflammatory cells consuming large amounts of oxygen create a hypoxic environment around the wound. Under such conditions, prolonged hypoxia inhibits angiogenesis and extracellular matrix (ECM) synthesis, reducing the nutrient supply to the injured area, thereby impeding further healing. Therefore, promoting tissue vascularization and enhancing nutrient delivery are crucial for facilitating tissue repair processes. To address this issue, we developed a graphene oxide (GO)-decellularized dermal matrix sponge (PGO_0.35T₁) with photothermal bath functionality. Through photothermal conversion, this sponge not only enhances cellular adaptation to oxygen and remodels the local tissue microenvironment, effectively regulating cellular metabolism, but also absorbs substantial light energy, achieving bacterial eradication via localized hyperthermia. Additionally, owing to the modification with tranexamic acid, this extracellular matrix sponge exhibits excellent hemostatic properties. In vitro experimental results demonstrated that the three-dimensional sponge scaffold possessed favorable cell adhesion, biocompatibility, and bioactivity. In a rat diabetic wound model, the PGO_0.35T₁ sponge scaffold effectively and continuously interacted with the wound, mimicking the role of natural skin, preventing the loss of internal nutrients, and creating a comfortable and conducive microenvironment for tissue regeneration. Furthermore, it enhances epithelialization by increasing the number of microvessels in the skin. Thus, this oxygen-rich short-fiber sponge with photothermal bath functionality regulates cellular metabolism, offering a novel approach for diabetic wound repair through its antibacterial, photothermal, and metabolic-improving properties, with significant clinical implications.