Injectable, conductive MXene@Mg2+ hydrogel with photothermal antibacterial and angiogenic properties for bacteria-infected wound healing

Bacterial infection is the most common problem in wound healing, and the severe inflammatory response it triggers can significantly increase associated complications and delay the healing process. Consequently, developing effective antimicrobial wound dressings presents a substantial challenge. Herein, a versatile hydrogel namely PVA/POA-MX@Mg 2+ was fabricated on the basis of Polyvinyl alcohol (PVA), phenyl boric acid (PBA)-grafted oxidized hyaluronic acid (POA), and magnesium coated MXene nanosheets (MXene@Mg 2+ ). The hydrogel features reversible borate ester bonds for automatic repair and self-healing, adapting to complex wounds, while residual aldehyde groups enhance its adhesiveness. It was observed that increasing the proportion of aldehyde groups in the hydrogel system enhances its adhesion continuously, with the strength reaching up to 45 kPa. Besides, the PVA/POA-MX@Mg 2+ hydrogel exhibits excellent electrical conductivity, and effective photothermal antibacterial properties under near-infrared (NIR) light irradiation, achieving antibacterial efficiencies of approximately 97.6 % against E. coli and 99.1 % against S. aureus. Furthermore, the photothermal capabilities of the hydrogel significantly enhance the healing of bacterial-infected wounds when combined with NIR stimulation. On day 14, treatment using the PVA/POA-MX@Mg 2+ hydrogel under NIR irradiation resulted in a wound healing rate of 99.6 %. This improvement is attributed to the hydrogel’s potent anti-inflammatory effects, promotion of cell proliferation, and facilitation of angiogenesis. This study underscores the pivotal role of multifunctional two-dimensional (2D) MXene@Mg 2+ nanocomposites in treating infected wounds. In summary, the PVA/POA-MX@Mg 2+ hydrogel demonstrates high antibacterial efficiency, suitable conductivity, excellent self-healing properties, and favorable biocompatibility, making it a promising candidate for wound healing dressings in treating infected skin wounds.