Folic Acid‐Modified Nanoprobe for In Vivo‐Targeted Persistent Luminescence Imaging and pH‐Responsive Antibiotic Therapy of Bacterial Infection

Abstract Low antibiotic utilization and inability to achieve real‐time monitoring of pathological status and treatment processes often result in unsatisfactory performance against bacterial infection. Developing a targeting antibacterial nanoprobe combining imaging with stimulus‐response antibiotic release is a promising strategy to precisely recognize lesions and enhance therapeutic efficacy for bacterial infection. In this work, we report a pH‐responsive theragnostic nanoplatform for targeted imaging and local drug release at the bacterial infection site. The nanoplatform consists of the core‐shell structure with persistent luminescence nanoparticles (PLNPs) as the core for autofluorescence‐free luminescence imaging and zeolitic imidazolate framework‐8 (ZIF‐8) as the shell to act as a carrier for antibiotics cefazolin. The core‐shell nanostructure is further conjugated with folic acid to facilitate the uptake and accumulation of the nanoparticles, and realize the autofluorescence‐free targeted imaging of the infection site. The acidic microenvironment at the bacterial infection site enables ZIF‐8 to decompose for specific drug release improve the performance in bacterial infection treatment. The developed pH‐responsive nanotheranostic probe is promising for autofluorescence‐free targeted imaging and therapy of bacterial infection.