Efficient antibacterial study based on near-infrared excited metal–organic framework nanocomposite

Near-infrared light-triggered UCNR@ZIF-67 antibacterial nanomaterials were constructed by combining β-NaYF4:Yb,Tm,Gd up-conversion nanorods (UCNRs) with near-infrared light response and Zeolitic Imidazolate Frameworks (ZIF-67) through the layer-by-layer self-assembly method. The optical properties, structure, composition, and morphology of UCNR@ZIF-67 were investigated by using UV–vis diffuse reflectance spectroscopy, X-ray diffraction and transmission electron microscopy. Reactive oxidizing species (ROS) detection indicated that the UCNR@ZIF-67 owned a good photodynamic efficacy. UCNR@ZIF-67 exhibited low toxicity and good biocompatibility by CCK-8 method. About 99.3% of E. coli and 99.1% of S. aureus were killed by UCNR@ZIF-67 under 980-nm laser irradiation for 25 min (1.0 W/cm2). Under 980-nm laser excitation, UCNRs generated ultraviolet and visible light to activate ZIF-67 and produced a large number of electron/hole pairs (e−/h+), which can react with O2 and H2O to produced ROS for antibacterial applications.