Diabetic foot ulcer is a serious complication in diabetes patients, imposing a serious physical and economic burden to patients and to the healthcare system as a whole. Oxidative stress is thought to be a key driver of the pathogenesis of such ulcers. However, no antioxidant drugs have received clinical approval to date, underscoring the need for the further development of such medications. Hydrogels can be applied directly to the wound site, wherein they function to prevent infection and maintain local moisture concentrations, in addition to serving as a reservoir for the delivery of a range of therapeutic compounds with the potential to expedite wound healing in a synergistic manner. Herein, we synthesized Prussian blue nanoparticles (PBNPs) capable of efficiently scavenging reactive oxygen species (ROS) owing to their ability to mimic the activity of catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD). In the context of in vitro oxidative stress, these PBNPs were able to protect against cytotoxicity, protect mitochondria from oxidative stress-related damage, and restore nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase-1 (HO-1) pathway activity. To expand on these results in an in vivo context, we prepared a thermosensitive poly (d,L-lactide)-poly(ethylene glycol)-poly(d,L-lactide) (PDLLA-PEG-PDLLA) hydrogel (PLEL)-based wound dressing in which PBNPs had been homogenously incorporated, and we then used this dressing as a platform for controlled PBNP release. The resultant PBNPs@PLEL wound dressing was able to improve diabetic wound healing, decrease ROS production, promote angiogenesis, and reduce pro-inflammatory interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels within diabetic wounds. Overall, our results suggest that this PBNPs@PLEL platform holds great promise as a treatment for diabetic foot ulcers.

cause of nontraumatic limb amputations, threatening patient health and quality of life. [1,2] Wound healing is a fascinatingly complex biological process. Traditionally, it is divided into four overlapping phases: hemostasis, inflammation, proliferation and remodeling. [3,4] Compared with the healing of other wounds, the healing of diabetic wounds gets stalled in the inflam matory phase, which is characterized by excessive production of reactive oxygen species (ROS), proinflammatory cytokines and proteases. [5,6] Excessive ROS produc tion cause irreversible oxidative damage to biomacromolecules (such as lipids, nucleic acids, and proteins) and the cells within the wound (such as endothelial cells, keratino cytes, and fibroblasts). This inhibits angiogenesis, granulation tissue forma tion, and wound healing. [7,8] The endo genous antioxidant system is inadequate to remove excessive ROS, and the use of exogenous antioxidants is recommended to prevent oxidative stress damage. With the rapid advancements in nanomedicine, numerous antioxidative nanomaterialsincluding melanin nanoparticles (NPs), metalbased nanomaterials (Au, Ag, Pt NPs), metal oxidebased nanomaterials (CeO 2 , Fe 3 O 4 , TiO 2 , alumina, SiO 2 ), [9,10] and quantum dots-are being used in wound dressing systems to scavenge excess ROS. [11] In addition to oxidative damage, bacterial infections also hinder diabetic wound healing. [12,13] Diabetic wounds are more prone to bacterial infection owing to impaired immune responses, and bacterial infections cause increased ROS pro duction and worsen the inflammatory response in wounds. [14,15] Bacteria easily acquire multidrug resistance owing to antibi otic misuse. Therefore, among various available antimicrobial therapies, photothermal therapy (PTT) has been attracting widespread attention. [16] In PTT, nearinfrared (NIR) laser irra diation is used to induce a local increase in temperature, which can damage bacterial cell membranes and denature bacterial proteins, thus causing bactericidal effects. [16,17] So far, a variety of nanomaterialbased photothermal agents have been incorpo rated into wound dressings to treat bacteriainfected wounds. [17] However, monotherapy with PTT may lead to additional local ROS production, thus delaying wound healing. Therefore, anThe treatment of diabetic wounds remains challenging due to the excess levels of oxidative stress, vulnerability to bacterial infection, and persistent inflammation response during healing. The development of hydrogel wound dressings with ideal anti-inflammation, antioxidant, and anti-infective properties is an urgent clinical requirement. In the present study, an injectable thermosensitive niobium carbide (Nb 2 C)-based hydrogel (Nb 2 C@Gel) with antioxidative and antimicrobial activity is developed to promote diabetic wound healing. The Nb 2 C@Gel system is composed of Nb 2 C and a PLGA-PEG-PLGA triblock copolymer. The fabricated Nb 2 C nanosheets (NSs) show good biocompatibility during in vitro cytotoxicity and hemocompatibility assays and in vivo t...

In recent years, there has been rapid progress in MXene research due to its distinctive two-dimensional structure and outstanding properties. Especially in biomedical applications, MXenes have attracted widespread favor with...

Wounds occur when skin integrity is broken and the skin is damaged. With progressive changes in the disease spectrum, the acute wounds caused by mechanical trauma have been become less common, while chronic wounds triggered with aging, diabetes and infection have become more frequent. Chronic wounds now affect more than 6 million people in the United States, amounting to 10 billion dollars in annual expenditure. However, the treatment of chronic wounds is associated with numerous challenges. Traditional remedies for chronic wounds include skin grafting, flap transplantation, negative-pressure wound therapy, and gauze dressing, all of which can cause tissue damage or activity limitations. Nanobiotechnology — which comprises a diverse array of technologies derived from engineering, chemistry, and biology — is now being applied in biomedical practice. Here, we review the design, application, and clinical trials for nanotechnology-based therapies for chronic wound healing, highlighting the clinical potential of nanobiotechnology in such treatments. By summarizing previous nanobiotechnology studies, we lay the foundation for future wound care via a nanotech-based multifunctional smart system.

No abstract