Fe_3O_4磁性纳米粒子的PEG修饰剂的合成与性能  

Synthesis and Properties of PEG Modifier Based on Fe_3O_4 Magnetic Nanoparticles

作　　者：季帆 曾恺[1] 张坤[1] 李杰[1] 张剑锋[1] 

机构地区：[1]宁波大学材料科学与化学工程学院,宁波315211

出　　处：《高分子学报》2016年第12期1704-1709,共6页Acta Polymerica Sinica

基　　金：国家星火计划(项目号2015GA701037);浙江省公益性技术应用研究计划(项目号2015C31044);宁波大学研究生教研项目(项目号JGZDI201302)资助

摘　　要：采用共沉淀法制备了用柠檬酸包覆的Fe3O4磁性纳米粒子,为提高其生物环境适应性和生物应用,利用聚乙二醇二胺(NH2-PEG-NH2)通过碳二亚胺化学法进一步修饰,得到具有良好性能的磁性纳米粒子修饰剂,并分别用场发射扫描电子显微镜(SEM)、洛伦兹透射电子显微镜(TEM)、马尔文激光粒度仪、X-射线粉末衍射仪(XRD)、傅里叶变换红外光谱(FTIR)、综合热分析仪(TG/DTA)、振动样品磁强计(VSM)对磁性纳米粒子的表面形态、化学结构、晶体结构、热稳定性和磁性能进行了表征.在此基础上用合成的磁性纳米粒子修饰剂对盐酸阿霉素(DOX·HCl)进行了修饰,研究了修饰剂的载药和释药行为.结果表明,所制备的修饰剂近乎球形,尺寸相对均匀,粒径在15 nm左右,饱和磁化强度为68 A·m2/kg,在磁靶向药物运输中可以达到良好的磁响应性能.在水中的载药量达到83%,在p H=7.4和p H=5.0下,磁性纳米粒子载药盐酸阿霉素释放均是一个缓慢的过程,具有明显的缓释效果,此外,由于不同p H值下,DOX中的氨基质子化程度存在差异,在较低的p H值下质子化的氨基互相排斥,这更有利于DOX的释放,累计释药率在72 h后分别为65.8%(p H=7.4)与73.6%(p H=5.0).研究表明该磁性纳米粒子具有很好的载药能力及缓释效果.Fe3O4magnetic nanoparticles coated by citric acid were synthesized via co-precipitation,and NH2-PEG-NH2-modified magnetic nanoparticles（PCMNPs） were thus prepared by carbodiimide chemistry to improve biological application of the nanoparticles. The surface morphology,chemical structures,crystal structures,thermostability and magnetic properties of the nanoparticles were characterized with scanning electron microscopy（SEM）,Lorenz transmission electron microscopy（TEM）,Malvern laser particle size analyzer,X-ray analysis（XRD）,Fourier transform infrared spectroscopy（FTIR）,thermogravimetric analysis（TGA） and vibrating sample magnetometer（VSM）. Doxorubicin（DOX） was used as a model drug to study the PCMNPs drug loading and release behaviors,and DOX-loaded nanoparticles（PCMNPs-DOX） were then prepared,accordingly. The PEG modifier nanoparticles were roughly spherical with a relatively uniform size of about 15 nm. The size analysis showed that the as-synthesized magnetic nanoparticles were of statistical distribution with a maximal diameter of 33 nm. FTIR data and TG results all revealed that polymer PEG formed complexes on Fe3O4 surface. VSM result disclosed that no coercivity or remanence could be observed for samples,suggesting the superparamagnetic properties of the particles. The saturation magnetization（Ms） of the MNPs was about 68 A·m^2/kg,which could be used for magnetic drug targeting delivery,hyperthermia treatment and magnetic resonance imaging. Consequently,the drug loading capacity in water was about 83%.The overall release efficiency was higher at a lower p H（5. 0） than at physiological p H（7. 4）,which was important for the killing of relatively acidic tumor cells. Furthermore,the release of DOX from PCMNPs in both conditions showed that drug molecules released at a sustained pattern and complete release of drug was not attained. All the characterizations indicated that the PEG modifier nanoparticles showed superparamagnetic performance,high drug loading ability

关 键 词：四氧化三铁 磁性纳米粒子 柠檬酸 聚乙二醇二胺 阿霉素 

分 类 号：TQ460.1[化学工程—制药化工]