Polyoxometalate-based heterojunction with NIR light-facilitated photocatalytic W6+/W5+ redox cycling for enhanced bacteria-infected wound healing

Metal-based nanomaterials with shifting or mixed redox states have been widely applied for combating against bacteria-infected diseases by virtue of their peroxidase (POD)-like catalytic activity. Herein, a polyoxometalate-based heterojunction (GdP 5 W 30 @WS 2 ) with shifting or mixed redox states (W 6+ /W 5+ ) is devised to achieve boosted reactive oxygen species (ROS) generation by near-infrared (NIR) laser-facilitated W 6+ /W 5+ redox cycling for accelerated bacteria-infected wound healing. On the one hand, under the exposure to NIR laser, WS 2 as electron donor could be stimulated to transfer electrons to GdP 5 W 30 , which promotes the reduction from W 6+ to W 5+ active sites on the surface of the GdP 5 W 30 . Consequently, the regenerated W 5+ active sites could catalyze endogenous overexpressed H 2 O 2 to persistently generate ROS, which displays enhanced POD-like catalytic activity for chemodynamic therapy (CDT) by NIR-driven photocatalytic W 6+ /W 5+ redox cycling. Moreover, GdP 5 W 30 @WS 2 also displays favorable glutathione (GSH)-activated photothermal performance by W 6+ -triggered GSH exhaustion for sufficient ROS generation, thereby facilitating the synergistic therapeutic efficiency of photothermal therapy (PTT) and CDT. We expect that the present work will promote the development of the heterojunction with shifting or mixed redox states for biofilm elimination based on NIR-facilitated enzyme-like catalytic activity, which may act as a candidate for BME-activated synergistic therapy.