Studies of Drug Delivery System Based on Folic Acid Modified Core-Shell Magnetic Metal-Organic Frameworks

Abstract

The core-shell structure of magnetic Metal-Organic Frameworks (MMOFs) was composed of magnetic nanoparticles (MNPs) based on γ-Fe₂O₃@SiO₂-NH₂-COOH, metal salts and ligands. The imatinib (IMA-3) and methotrexate (MTX) were loaded into the MMOFs via one-pot reaction, and the release performance of MMOFs was explored. Amino groups were introduced into the MMOFs by Post-Synthetic Modification (PSM) of diethylenetriamine (2,3-NH₂) and 4-aminopyridine (4Py). Dye adsorption testing was used as a characterization method to verify the degree of Post-Synthetic Modification of samples. Three types of MMOFs with good degrees of modification were selected through methyl orange adsorption, followed by the folic acid modification. The successful modification of folic acid (FA) of the MMOFs was verified by methylene blue adsorption. By a variety of representational means, the synthesis and PSM were confirmed by infrared spectroscopy (IR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Comparing the release performance in vitro of MMOFs loaded with imatinib (IMA-3) and methotrexate (MTX), it showed that the release performance of MMOFs loaded with MTX was better. The release performance of MTX before and after the modification of MMOFs was compared, which indicated that the drug delivery performance of MMOFs might not be significantly affected after PSM.