Flexible photothermal biopaper comprising Cu2+-doped ultralong hydroxyapatite nanowires and black phosphorus nanosheets for accelerated healing of infected wound

Cutaneous wounds accompanied by bacterial infections and impaired angiogenesis might be lethal and remain a challenging issue in clinical fields, causing an urgent need for the multifunctional wound dressings with effective disinfection and wound tissue regenerative abilities. Herein, we report a flexible photothermal biopaper (named BP/HAP:Cu2+) with the integration of two-dimensional photothermal-capable black phosphorus nanosheets (BPNSs) and one-dimensional antibacterial Cu2+-doped ultralong hydroxyapaptite (HAP:Cu2+) nanowires for accelerated healing of the infected wound. The as-prepared BP/HAP:Cu2+ biopaper exhibits the stable porous networked structure, high porosity, good biocompatibility, superior photothermal conversion ability and antibacterial function. The photothermal effect generated by BPNSs conjugated with the sustained release of Cu2+ ions can damage the bacterial membrane and enhance glutathione oxidation, achieving a synergistic high antibacterial efficiency on Staphylococcus aureus of 97.0%. Moreover, the BP/HAP:Cu2+ biopaper can effectively promote in vitro angiogenesis of human umbilical vein endothelial cells. Results of animal experiments further reveal that the BP/HAP:Cu2+ biopaper as the wound dressing under near infrared laser irradiation significantly enhances the wound healing by simultaneously eliminating bacteria and accelerating angiogenesis. Taken together, the BP/HAP:Cu2+ photothermal biopaper has a promising therapeutic potential for rapid healing of infected wounds.