Synthesis of Metal-Organic Framework with Fe and Mo as central metals and Its Biological Effects on Azotobacter vinelandii

Hua Chen

Metal-organic framework; Metal element; nitrogen fixation; Oxidative stress; Environmental effects

This study successfully synthesized metal-organic framework with Fe and Mo as central metals (FeMo-MOF), with XRD, SEM and XPS characterizations confirming its bipyramidal morphology and expected Mo/Fe coordination structure. At concentrations of 20-60 mg/L, colony forming units (CFU) doubled, with the fastest logarithmic growth rate observed at 20 mg/L. However, higher concentrations (80-100 mg/L) limited CFU growth due to physical damage caused by the material's sharp edges. The 20 mg/L treatment group showed a 20% increase in nitrogenase activity, while ¹⁵N isotope analysis indicated a slight (statistically insignificant) improvement in total nitrogen fixation, attributed to Mo released from the MOF acting as a nitrogenase cofactor. Although FeMo-MOF did not alter GSH levels (indicating unactivated antioxidant systems), elevated MDA content demonstrated that the material's sharp structure induced membrane lipid peroxidation damage. This research provides important insights for environmentally friendly MOF design: balancing metal selection (prioritizing non-toxic metals) with morphology optimization (reducing physical damage) to achieve efficient and safe agricultural applications.

https://doi.org/10.31871/IJNTR.11.5.13