聚乙二醇/聚乙烯吡咯烷酮修饰的纳米Fe3O4粒子的制备与表征

为了获得能够在水中稳定分散,具有广泛应用前景的磁性纳米粒子,以不同分子量的聚乙烯吡咯烷酮(PVP)作为修饰剂,在聚乙二醇(PEG)中高温热分解乙酰丙酮铁(Fe(acac)₃)制备了纳米Fe₃O₄粒子。采用X射线粉末衍射仪(XRD)、透射电镜(TEM)、高分辨透射电镜(HRTEM)、超导量子干涉仪(SQUID)、热重分析仪(TGA)、傅里叶变换红外光谱仪(FT-IR)、纳米粒度与zeta电位分析仪对样品进行了表征,并对样品在生理盐水和生理缓冲液中的稳定性进行了研究,结果表明:制备的纳米Fe₃O₄粒子具有高的结晶度以及单分散性,在300 K下,具有超顺磁性和较高的饱和磁化强度;PEG和PVP共同修饰于纳米Fe₃O₄粒子表面,为纳米Fe₃O₄粒子提供了良好的水分散性;制备的纳米Fe₃O₄粒子在生理盐水和多种生理缓冲液中能够高度溶解并稳定地分散。水中的纳米Fe₃O₄粒子表面呈电中性,表面修饰层的空间位阻效应是所制备的纳米粒子在水溶液中高分散的原因。

Synthesis and characterization of Fe3O4 nanoparticles coated with poly(ethylene glycol)and poly(vinyl pyrrolidone)

To obtain magnetic nanoparticles (NPs) with good water dispersibility, Fe₃O₄ nanoparticles were synthesized by thermal decomposition of the iron(Ⅲ) acetylacetonate (Fe(acac)₃) in poly(ethylene glycol) (PEG) containing poly(vinyl pyrrolidone) (PVP) of different molecular weight as modifying agents.The samples were characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), superconductivity quantum interference device (SQUID), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), and particles &; zeta potential analyser.The stability of Fe₃O₄ nanoparticles dispersed in physiological saline and physiological buffers was investigated.The prepared Fe₃O₄ nanoparticles had high crystallinity, and showed superparamagnetic behavior at 300 K with higher saturate magnetization.The surfaces of Fe₃O₄ nanoparticles were modified by PEG and PVP which provided good water dispersibility.The Fe₃O₄ nanoparticles revealed high dissolubility and stability in physiological saline and physiological buffers.The surfaces of Fe₃O₄ nanoparticles were electrically neutral in water, and steric hindrance effect of the surface modified layer might be the main reason for high dispersion stability of the prepared nanoparticles in aqueous solution.