Photo-responsive antibacterial metal organic frameworks

The misuse and overuse of antibiotics have caused the emergence of antibiotic-resistant bacteria, making bacterial infections more challenging. The increasing prevalence of multidrug-resistant pathogens has driven researchers to explore novel therapeutic strategies. Phototherapy strategies that utilize photo-responsive biomaterials for their antibacterial properties have gained widespread attention due to their capability of precisely controlling bacterial inactivation with minimal side effects. Despite their potential, photodynamic therapies suffer from phototoxicity and low efficiency of photosensitizers, while photothermal therapy risks overheating, which may harm healthy tissues, thus restricting its broader application. Metal organic frameworks (MOFs) have unique physicochemical properties, which provide a promising way to deal with these challenges. MOFs can function as reservoirs, loading and releasing antibacterial agents, such as antibiotics or metal ions, upon light illumination by virtue of their metastable coordination bonds. Their porous structures enable controlled drug release and encapsulation of photosensitizers. Furthermore, MOFs' tunable composition and pore structure allow for the light-triggered generation of heat and reactive oxygen species, enhancing their antibacterial effectiveness. By doping MOFs with functional materials, it is possible to achieve multi-mode antibacterial effects. In this review, we will outline recent advancements of photo-responsive antibacterial MOFs, categorize their underlying mechanisms of action and highlight their prospects in addressing bacterial resistance.