Abstract:
Background Superparamagnetic iron oxide nanoparticles (SPIONs) are special magnetic nanoparticles with a particle size of 1-100 nm. Due to their high magnetic response, large specific surface area, good biocompatibility, and low toxicity, they are widely used in biomedical and clinical research.
Objective To study the drug-carrying performance and in vitro biocompatibility of Zn0.3Fe2.7O4 magnetic nanoparticles synthesized by high-temperature organic solvent method loaded with imiquimod.
Methods Polyethylene glycol (PEG) and imiquimod (R837) were fabricated on the surface of Zn0.3Fe2.7O4 by reverse evaporation method, and folic acid (FA) was further modified on the surface to construct a magnetic nano-drug carrier composite system. Using X-ray diffraction (XRD), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), dynamic light scattering (DLS), etc, the structure, morphology and performance of the composite nanomaterial system were analyzed. The drug-carrying performance of the system was evaluated using HPCL. CCK8 assay was used to detect the toxicity of the composite nanoparticles on mouse embryonic fibroblast cells (MEF) and human osteosarcoma MG63 cells.
Results PEG and R837 were successfully modified to the surface of Zn0.3Fe2.7O4. The drug loading rate of the composite nanomaterial system was 4.40%, the encapsulation rate was 87.90%, and the folic acid was further modified on the surface. In the sustained release test of the drug, the release amount reached 27.31% with the temperature of 37℃ at 6 h, and 45.86% with the temperature of 43℃. Zn0.3Fe2.7O4-PEG-R837 and its biological toxicity to MEF, MG63 were tested. After 48 h incubation, there was no toxicity with the concentration below 600μg/mL.
Conclusion The synthesized Zn0.3Fe2.7O4-PEG-R837 composite magnetic nano-drug carrier system has good drug-carrying performance and low toxity.