中文摘要：

共沉淀法是制备磁性微小铁葡聚糖颗粒的常用方法之一,其简单、易操作,但是温度、pH、氨水滴加速度等多种因素影响粒径的大小,而且很多颗粒聚集成束,因而微小铁葡聚糖颗粒的回收量低。为提高微小铁葡聚糖颗粒的回收量,对反应初产物离心后的沉淀部分进行了超声波处理,使回收量由处理前的0.5g提高到处理后的10g以上。利用回收的微小铁葡聚糖颗粒进行纤毛虫接合对分离,接合率高达95%以上。

英文摘要：

＂ Co-precipitation＂ is one of the most popular methods for preparation of magnetic iron-dextran particles, which is simple and easy to operate. These particles can be obtained by dissolving FeCl2, FeCl3 together with dextran in H2O in a proper ratio and adding NH4 OH into this solution. After the chemical reaction completed, the poduct is dark-brown including numerous different sized magnetic iron-detran particles and their aggregates due to the effects of temprature, pH, the speed of NH40H addition and some other factors. In fact, the primary reaction product is centrifuged to eliminate the large particles and to obtain ideal-sized particles, while this centrifugation results in the loss of the most primary reaction product and low production of the idealsized particles. In this experiment, the pellet from the centrifugation was treated with ultrasound, and as the result, the production of magnetic iron-dextran particles was increased to 20 times of the original production from 0. 5 g to 10 g. When these particles were added to the mixtures of singel cells and conjugating pairs of Paramecium caudatum, highly synchronized conjugating pairs were obtained, which indicates its high quality of the particles. The importance of the current improvement for preparation of magnetic iron-dextran particles can be evaluated by its universal use in bioseienee, biomedical and bioengineering due to their excellent biocompatibility and targeting performance.