Preparation and Characterization of Fe3O4@SiO2@NMDP core-shell structure composite magnetic nanoparticles

Fe3O4@SiO2@nimodipine(NMDP) core -shell structure nanoparticles were prepared successfully by sonochemical method. The composite magnetic nanoparticles with SiO2 coating are effective and accurate for completing the delivery of NMDP in vitro. The samples are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR). Drug release was detected by high performance liquid chromatography (HPLC). The result shows the release rate of NMDP reach to 61.3% in a short time of 40 min in the PBS, and to 100% in a time of 60 min. The Fe3O4@SiO2@NMDP NPs prepared show a super paramagnetic property with a saturation magnetization value of 21.4 emu/g. The accordingly composite magnetic fluid with a saturation magnetization value of 14.8 emu/g shows the spicules in external magnet field. It indicates that SiO2 coating plays an important role and has a great potential application in treatment of high blood pressure and cerebrovascular disease by using magnetic drug delivery technology.