Pathogenic microbes and house dust mites (HDM) are critical factors associated with severe asthma and pathogenic infections that severely threaten human health worldwide. Therefore, it is urgent to develop biocide alternatives to inactivate pathogenic microbes and HDM, and to reduce immunogenicity of HMD. Silver (Ag)/titanium dioxide (TiO2) nanoparticle (ATN) exhibits a significant synergistic enhancement effect due to destructive reactive oxygen species (ROS) generation under UV irradiation, while its antimicrobial and acaricidal activities and related action mechanisms without light irradiation are still unclear. Herein, a water-dispersible ATN was prepared facilely by a photocatalytic reduction process. ATN exhibited improved antimicrobial activity due to synergistic antimicrobial effect of Ag and TiO2 based on destructive nitric oxide (NO) generation in the absence of light. And ATN exhibited good acaricidal activity against HDM due to oxidative stress-induced mitochondrial disorder, lysosome swelling and rupture arising from NO generation. Especially, ATN can effectively reduce immunogenic Dermatophagoides farinae group 1 (Der f 1) and Dermatophagoides farinae group 2 (Der f 2). The work proposes an alternative approach to develop biocide alternatives and acaricidal materials, and it can help readers better comprehension of synergistically enhanced antimicrobial and acaricidal activities and relative action mechanisms of meta doped TiO2 nanoparticles.
Liu et al. (Fri,) studied this question.