Metal-organic framework/poly (ε-caprolactone) hybrid electrospun nanofibrous membranes with effective photodynamic antibacterial activities

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 coil (E. coil) 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.