Responsive nanoplatform for persistent luminescence "turn-on" imaging and "on-demand" synergistic therapy of bacterial infection

Abstract

Multifunctional nanotheranostic platforms are emerging for the treatment of bacterial infections. Uncontrollable drug release and poor response in target location leads to inefficient therapy and failure to offer timely antibacterial monitoring. Here, we report a multifunctional nanoplatform that can be triggered by the bacterial microenvironment for effective bacterial killing and high-sensitive persistent luminescence (PL) "turn-on" imaging. Hyaluronic acid (HA) is grafted on the surface of mesoporous silica-coated persistent luminescence nanoparticles (PLNPs@MSN) loaded with cinnamaldehyde (CA). Further in situ growth of MnO₂ shells gives PLNPs@MSN@CA-HA-MnO₂ (PMC-HA-MnO₂). MnO₂ shell of PMC-HA-MnO₂ can be reduced to Mn²⁺ by the H₂O₂ in the bacterial microenvironment to trigger persistent luminescence (PL) "turn-on" imaging along with chemodynamic therapy (CDT). Meanwhile, HA can response to bacterially secreted hyaluronidase to make the packaged CA release controllable and "on-demand". Consequently, PMC-HA-MnO₂ enables effective response to bacterial-infected region, ensuring high-sensitive "turn-on" imaging, synergistic CDT, accurate targeting and "on-demand" CA release to give great antibacterial effect. This nanoplatform has great potential for the diagnosis and treatment of multidrug-resistant bacterial infection with high specificity and efficiency.

Keywords: Bacterial infection; Microenvironment-responsive theranostics; On-demand; Persistent luminescence imaging; Synergistic therapy.