Green Synthesis of Gallium-Based Metal-Organic Frameworks with Antibacterial Properties

Bacterial drug resistance has become increasingly severe, with the development of novel antibiotics lagging far behind the evolution of resistant strains, drastically limiting clinical treatment options. Therefore, the development of new antibacterial materials is urgently needed. In this study, we synthesized a gallium-based metal-organic framework antibacterial material, designated as GM, with gallium as the central atom. Compared to a previously reported gallium-based MOF (FM), GM features a greener and milder synthesis process (room temperature, aqueous solvent, no toxic additives) while exhibiting improved antibacterial performance. Despite sharing identical raw materials, GM and FM are structurally distinct due to differences in synthesis methods, as evidenced by variations in morphology and crystal structure. Antibacterial assays against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) demonstrated that GM outperforms FM, particularly against S. aureus, where GM exhibits threefold higher efficacy. Mechanistic investigations revealed that GM induces substantially higher intracellular reactive oxygen species levels and stronger disruption of bacterial membrane potential compared to FM, which may underpin its enhanced antibacterial activity. Additionally, cytotoxicity tests confirmed that GM shows no significant toxicity to mammalian cells. This study presents a gallium-based MOF prepared via a green synthesis route, with favorable antibacterial efficacy and biocompatibility, offering insights and a reference for the development of non-antibiotic antimicrobial agents.