Self-detoxifying hollow zinc silica nanospheres with tunable Ag ion release-recapture capability: A nanoantibiotic for efficient MRSA inhibition

Nanoparticle-enabled strategies to combat antimicrobial-resistant (AMR) bacteria are highly demanded, which hopefully can overcome the barriers associated with conventional antibiotics to achieve high therapeutic efficacy by improving pharmacokinetics. Here, we report the controlled fabrication of multiple Ag nanoparticles (AgNPs) containing ZIF-8 derived hollow -Zn-O-Si- nanospheres with mesoporous wall, Ag&Zn@mesSiO2, which can release and recapture Ag+ ions, thus, efficiently eradicate planktonic methicillin-resistant Staphylococcus aureus (MRSA) in vivo. The AgNPs encapsulated inside the large internal cavities of the hollow structure can kill MRSA at significantly reduced dosages due to the synergistic effect of released Zn and Ag ions, which was 10 times lower in comparison with single Ag+ application. The boomerang-like release-and-recapture scheme of the Ag+ ions helps to greatly reduce the notorious Ag toxicity. Such novel structured nanocomposites with widened Ag therapeutic window possess great potential as nanoantibiotic for tackling MRSA infection.