Photothermal-antibacterial bioactive noncrystalline nanosystem promotes infected wound tissue regeneration through thermo-ions activation

The efficient repair and tissue regeneration of chronic infected wounds is still a major challenge, among which the bacterial infection, inflammation and oxidative stress induced poor angiogenesis are the key obstacles. The nanosystem with single repair pathway could not meet the requirement of regenerating complicated wound tissue. Herein, we construct an photothermal multifunctional bioactive nanoglass (BGN) with the metal polyphenol coordination surface to treat methicillin-resistant Staphylococcus aureus(MRSA)infected wound. The BGN was coated with copper (Cu) coordinated polydopamine (PDA-Cu) to bioactive BGN@PDA-Cu nanoparticles, which release bioactive ions (Ca2+, SiO44- and Cu2+) and show the robust antibacterial/antioxidant/mild photothermal activities. BGN@PDA-Cu possesses the strong MRSA inhibition, reactive oxygen species scavenging, mild photothermal stimulation (41℃) and hemostatic ability. The antioxidant activity, thermal stimulation and sustainable bioactive ions release could significantly reverse the inflammatory phenotype of macrophage and enhance the angiogenesis through the activation of hypoxia-inducible factor HIF-1α and heat shock protein HSP90 pathways. The in vivo MRSA infected wound model demonstrated that BGN@PDA-Cu could significantly inhibit the MRSA infection and accelerate the wound repair which has 2 times improvement on healing rate compared with commercial bioglass dressing. This work demonstrates that bioactive ions release combined with mild thermal stimulation is a promising strategy to design multifunctional bioactive biomaterials for angiogenetic tissue regeneration.