Dynamic Microenvironment-Adaptable Hydrogel with Photothermal Performance and ROS Scavenging for Management of Diabetic Ulcer

Abstract

Persistent bacterial infections and excessive oxidative stress prevent the healing of diabetic ulcers, leading to an increased disability rate. Current treatments fail to kill bacteria while simultaneously relieving oxidative stress. Herein, a dynamic microenvironment-adaptable hydrogel (BP@CAu) with photothermal performance and reactive oxygen species scavenging is presented for diabetic ulcer healing. This hydrogel prepared using a dynamic borate-ester could respond to acidity in the infection microenvironment for a controllable drug release. An excellent photothermal conversion effect was integrated in the hydrogel, which exhibited strong antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The hydrogel attenuated intracellular oxidative stress and inflammation and promoted cell migration. In a full-thickness skin defect model of diabetic rats, the BP@CAu hydrogel contributed to the fastest wound closure, with ideal reepithelialization, granulation tissue formation, and regeneration of blood vessels. Further mechanistic studies revealed that the hydrogel relieved oxidative stress and downregulated the expression of inflammatory cytokines, resulting in dramatic therapeutic effects on diabetic wounds. Therefore, this study provides a synergistic therapeutic strategy for efficient photothermal performance and reactive oxygen species scavenging in diabetic ulcers.

Photothermal hydrogels for infection control and tissue regeneration

“…Similarly, Jia et al constructed a microenvironment-adaptive hydrogel, BP @ CAu by integrating gold nanorods (AuNRs) and curcumin nanorods (CNPs), in which AuNRs with a high photothermal conversion ability were used as PTAs. The BP@CAu hydrogel can be rapidly heated to 60 °C under 808-nm NIR irradiation, and the wound site has nearly no bacteria on the agar plate ( Figure 7C ) ( Jia et al, 2023 ).…”

“…(C) Antibacterial effect of BP@CAu hydrogels. Reproduced from ref ( Jia et al, 2023 ) with permission from ACS Appl. Mater.…”

Facile Reactive Oxygen Species-Scavenging Supramolecular Hydrogel to Promote Diabetic Wound Healing

“…Diabetes, a chronic metabolic disorder, is marked by consistent hyperglycemia. , An estimated 19–34% of individuals with diabetes experience impaired wound healing. − This impairment is often attributed to dysregulated angiogenesis and a protracted inflammatory response, which inhibit the normal healing processes in diabetic wounds. − Recent advances in wound care have highlighted hydrogels as promising therapeutic dressings due to their ability to maintain moisture at the wound site and to control drug release, thereby enhancing the treatment of chronic wounds. − Distinct from polymeric hydrogels, low-molecular-weight hydrogels, with constituent molecules under 1 kDa, demonstrate superior biocompatibility and reduced immunogenicity. , Supramolecular hydrogels, particularly those formed by self-assembling short peptides, are a subset of these materials. They are recognized for their inherent biocompatibility and tunable properties and have gained traction for a variety of biomedical applications. − …”