Fe3O4/SiO2复合磁性粒子的制备及其药物缓释行为

目的:采用共沉淀法和溶剂热法制备Fe_3O_4纳米磁性粒子,对其药物控释性能进行检测。方法:以正硅酸乙酯(TEOS)为前驱体,采用Stober法,在乙醇/水溶液中,通过氨水催化水解硅醇盐,制得核壳式结构的Fe_3O_4/SiO_2复合磁性微球;以X射线衍射(XRD)、扫描电子显微镜(SEM)、Fourier红外光谱(FTIR)等手段表征样品的结构,研究复合材料的耐酸性、磁分离行为及对药物布洛芬的缓释行为。结果:SEM显示Fe_3O_4与Fe_3O_4/SiO_2粒子均为纳米颗粒,粒径分布基本均匀;与溶剂热法比较,共沉淀法制得的Fe_3O_4晶粒结晶度较好,XRD衍射峰强,SiO_2的包裹使得Fe_3O_4尖锐的特征衍射峰稍微下降,表明包覆过程没有破坏其晶体结构,Fe_3O_4/SiO_2样品谱图中出现了无定型SiO_2的衍射峰,红外谱图同样出现了无定型SiO_2的透射峰。结论:表面二氧化硅的包覆显著改善了四氧化三铁纳米粒子的耐酸性,磁分离实验表明二氧化硅的包裹减弱了Fe_3O_4的磁性,布洛芬缓释实验表明Fe_3O_4/SiO_2复合磁性微球具有较好的药物缓释效果。

Perparation and Drug Delivery Behavior ofFe3O4/SiO2 Magnitic Nanoparticles

Objective: Magnetic nanoparticles were synthesized via the coprcciptation and the solvothermal-method,and the control releasing for drug was investigaed.Method:Using tetraethyl orthosilicate(TEOS) as a precursor,the Fe3O4/SiO2 composite microspheres were sunthesjzed via hydrolysis of silicon alkoxides catalyzed by ammonia in ethanol/water solution through a modified Stber method.The structure of the samples were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM), and Fourier transform infrared spectroscopy (FT-IR).Ibuprofen was chosen as a model drug to investigate the drug delivery behavior of magnetic composite.Result:The SEM revealed the size range of magnetic nanoparticles.In comparision with solvothermal mothod, the degree of crystallineity of coprccipitation method products Fe3O4 is higher,and the diffraction peak is stronger.The sharp diffraction peak of Fe3O4/SiO2 indicated that the coating didn't destroy the structure of crystal.Sample Fe3O4/SiO2 appeared amorphorous peak for SiO2 in XRD and Fourier transform infrared spectroscopy.Conclusion:The ability of acid resistance of Fe3O4 is enhanced with coating of SiO2,but the magnetic performanc for Fe3O4 is reduced.The control releasing experiment of ibuprofen showed that the Fe3O4/SiO2 has a significant effect on adsorption and releasing for drug.