Antibacterial agents with high antibacterial efficiency and bacteria-binding capability are highly desirable. Herein, we describe the successful preparation of Cu2WS4 nanocrystals (CWS NCs) with excellent antibacterial activity. CWS NCs with small size (∼20 nm) achieve more than 5 log (>99.999%) inactivation efficiency of both Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) at low concentration (<2 μg mL–1) with or without ambient light, which is much better than most of the reported antibacterial nanomaterials (including Ag, TiO2, etc.) and even better than the widely used antibiotics (vancomycin and daptomycin). Antibacterial mechanism study showed that CWS NCs have both enzyme-like (oxidase and peroxidase) properties and selective bacteria-binding ability, which greatly facilitate the production of reactive oxygen species to kill bacteria. Animal experiments further indicated that CWS NCs can effectively treat wounds infected with methicillin-resistant Staphylococcus aureus (MRSA). This work demonstrates that CWS NCs have the potential as effective antibacterial nanozymes for the treatment of bacterial infection.

Conventional thrombolytic drugs for vascular blockage such as tissue plasminogen activator (tPA) are challenged by the low bioavailability, off-target side effects and limited penetration in thrombi, leading to delayed recanalization. We hypothesize that these challenges can be addressed with the targeted and controlled delivery of thrombolytic drugs or precision drug delivery. A porous and magnetic microbubble platform is developed to formulate tPA. This system can maintain the tPA activity during circulation, be magnetically guided to the thrombi, and then remotely activated for drug release. The ultrasound stimulation also improves the drug penetration into thrombi. In a mouse model of venous thrombosis, the residual thrombus decreased by 67.5% when compared to conventional injection of tPA. The penetration of tPA by ultrasound was up to several hundred micrometers in thrombi. This strategy not only improves the therapeutic efficacy but also accelerates the lytic rate, enabling it to be promising in time-critical thrombolytic therapy.

instead of CMS NPs dispersion for the saline and saline + NIR-II groups. 10 min later, infected site of the mice was irradiated by 1064 nm laser (1 W cm −2) for 5 min for saline + NIR-II and CMS + NIR-II groups. The infected area was monitored and photographed daily. At the therapeutic day 16, the infected tissues were homogenized and diluted in saline by ultrasonication. Then, these dilutions (100 µL) were plated on LB agar plates. The number of CFU was counted after incubation for 18 h at 37 °C. At the therapeutic day 16, the infected tissues were harvested, fixed in paraformaldehyde solution (4%), paraffined, sectioned, and observed after H&E staining by an Olympus IX-71 microscope.