MIL-101(Fe)@Zn loaded Kaempferol: development and antimicrobial properties of a novel bio-based antimicrobial material

In recent years, the burden of disease caused by Staphylococcus aureus and Escherichia coli infections has been significant. Currently, the development of antibiotics faces severe challenges, as the long-term misuse of traditional antibiotics has accelerated the evolution of resistance, while the pace of novel drug development lags far behind the rate of bacterial evolution. Therefore, the development of new antibacterial agents is urgently needed. This study presents a metal-organic framework composite material loaded with zinc oxide and kaempferol (MIL-101(Fe)@Zn-KF). The prepared material was characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), ultraviolet-visible spectrophotometry (UV-Vis), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and zeta potential analysis. Peroxidase-like activity, biosafety and antioxidant property of the composite were evaluated. The in vitro antibacterial effect of the composite against Staphylococcus aureus and Escherichia coli was investigated using the plate coating method and bacterial growth curves experiment. The synthesized material exhibited multifunctionality, such as enzyme-like activity, antibacterial property and antioxidant capacity. Compared to MIL-101(Fe)@Zn, MIL-101(Fe) and kaempferol alone, the MIL-101(Fe)@Zn-KF composite demonstrated superior antibacterial effect, with inhibition rate of 98.76% and 98.34% against Staphylococcus aureus and Escherichia coli , respectively. MIL-101(Fe)@Zn-KF was able to catalyze hydrogen peroxide to generate reactive oxygen species, which synergized with the composite itself to exert bactericidal effect. Systematic evaluation of the cytotoxicity and hemolytic effect of MIL-101(Fe)@Zn-KF revealed the excellent biosafety and clinical potential of the composite. In summary, the composite material synthesized in this study combined peroxidase-like activity, antibacterial performance, antioxidant capacity and excellent biocompatibility, providing new insights for the development of efficient and safe antibacterial materials.