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Bacterial infections have posed a grave challenge to public health. Molecular fluorescent probes play increasing important roles in diagnosis and treatment of bacterial infections, but are frequently hindered by the aggregation‐caused quenching and low bacterial specificity as well as reduced bactericidal activity. Herein, metabolism‐driven nanoprobes (HF‐D‐Ala NPs) are reported for bacteria‐activated detection and following visible‐light induced inactivation. The nanoprobes are formed via facile self‐assembly of amphiphilic fluorescent small molecule (HF‐D‐Ala), showing strongly quenched fluorescence and enhanced photostability due to the dense aggregation of hydrophobic structural units. Once encountering with bacteria, HF‐D‐Ala NPs are disassembled into free HF‐D‐Ala, which can be further integrated into cell walls via bacterial metabolism. This progress can readily "turn‐on" the molecular fluorescence, realizing visual bacterial detection and imaging. Subsequently, the labeled bacteria can be effectively inactivated by carbon monoxide released from incorporated HF‐D‐Ala upon visible‐light. With good specificity and biocompatibility, HF‐D‐Ala NPs can selectively detect and inactivate bacteria in biofilms and bacteria co‐existing with mammalian cells, showing great potential for bacterial infection theranostic applications. [ABSTRACT FROM AUTHOR]

• Rose Bengal (RB) was encapsulated into ZIF-8 cavity to get photosensitive RB@ZIF-8. • Hybrid nanofibrous membranes with PDT effect were prepared by co-electrospun of RB@ZIF-8 and PCL matrix. • The membranes demonstrated effectively and controllably antibacterial performance upon visible light irradiation. • The as-prepared membrane significantly accelerated wound healing in a full-thickness infected skin wound model on mouse. Functionalization of electrospun mats with antimicrobial nanomaterials is an attractive strategy to prevent bacterial colonization and accelerate infected wound healing. Compared with the traditional antibacterial strategies relying on bactericides, photodynamic antimicrobial therapy (PDT) has received considerable attentions owing to its high efficiency and controllability. Herein, we demonstrated a feasible approach to produce antimicrobial electrospun mats through co-electrospinning of biodegradable PCL matrix and photosensitive metal-organic framework (MOF) nanocrystals. Briefly, rose bengal (RB) was one-step encapsulated into zeolitic imidazolate framework-8 (ZIF-8) to obtain photodynamic antimicrobial RB@ZIF-8 nanoparticles, followed by blended with PCL matrix to yield composited polymeric nanofibers via co-electrospun. By adjusting the contents of RB@ZIF-8 in PCL, sufficient MOF particles were presented on the nanofiber surfaces. Benefited from the reactive oxygen species (ROS) generation upon visible light irradiation, the nanofibrous membranes were able to dose and time-dependent inactivate of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) in vitro. Besides, the nanofibrous showed considerable low hemolysis activities. Moreover, a bacteria-infected wound healing experiment suggested that the nanofibrous membrane had a better ability to remedy bacteria wound infection and accelerate wound healing. This work would greatly expand the bioapplications of MOF materials and may assist in developing novel hybrid materials with the ability to hinder microbial infections. [ABSTRACT FROM AUTHOR]