医用葡聚糖磁性纳米微粒的制备及特性研究

Preparation and Characteristics of Dextran-coated Iron Oxide Nanoparticle

目的制备磁响应性强、粒径小且分布均匀的磁性纳米微粒,为消化道恶性肿瘤的磁控靶向治疗提供一种新型载体。方法利用超声波的粉碎空化作用,采用化学共沉淀法合成葡聚糖磁性纳米微粒。通过扫描电镜和原子力显微镜观察微粒的形态和大小,激光光散射粒度分析仪检测微粒的粒径及分布,磁强计检测微粒的磁响应性。结果该法制备的葡聚糖磁性微粒多呈球形或椭圆形,有效粒径为(93.1±2.2)nm,半峰宽为(26.7±1.3)nm,显示其粒径为纳米级,且大小均一。在外加场强为104Oe、外部温度为18℃的条件下微粒的磁响应强度为(26.0±1.1)emu/g,撤除磁场时剩磁为零,提示微粒具有顺磁性。结论用该法制备的葡聚糖磁性微粒,具有有效粒径小、粒径分布窄以及磁响应性好的优点,可作为一种新型靶向磁性载体,进行恶性肿瘤的磁控靶向治疗。

Objective To improve the method of synthesizing magnetic particles, which have good magnetic property and small size, to be used in tumor target therapy. Methods Dextran-coated iron oxide nanoparticles （DCIONPs） were prepared by ultrasonic and chemical coprecipitation method and the characteristics were evaluated. The size and shape of the particles were verified by scanning electron microscope （SEM）, the effective diameter and diameter distribution were determined by particle size analyzer, the morphology was investigated by atomic force microscope （AFM）, and the magnetic property was evaluated by magnetometer. Results Most of the DCIONPs showed shape of sphere or oval. The effective diameter was （93. 1±2.2） nm, the half width was （26.7±1.3） nm, as indicated that the DCI（）NPs were tiny and in conform size, The magnetic response was （26.0± 1.1 ） emu/g in a magnetic field of 104 Oe and the remanence was zero without it, suggesting the nanoparticles＇ paramagnetism. Conclusion The DCIONPs prepared by ultrasonic coprecipitation method have the advantages of small size, nar row distribution and good magnetic property, and can be used as the magnetic carrier for drug or gene target delivery.