脉冲电场制备磁性Fe_3O_4海藻酸盐微球的工艺研究

以Fe_3O_4纳米粉末作为磁性材料,以海藻酸钠、壳聚糖作为微胶囊制备材料,以大肠杆菌为细胞模型,以CaCl_2为交联剂,采用脉冲电场微球成型工艺制备载细胞磁性微胶囊。以微球粒径为检测指标,正交设计考察显著影响因素及影响规律。采用振动磁强计测定徽囊的饱和磁化强度。实验结果表明,海藻酸钠溶液浓度是影响载磁微球粒径的显著因素。在Fe_3O_4浓度为1 mg/mL、海藻酸钠浓度为10 mg/mL金属锐孔孔径为450μm、泵速4 mL/h、CaCl_2浓度为20 mg/mL的工艺条件下,制备了球形度均匀、分散性好、具有强磁响应性、平均粒径132.2μm的超顺磁性微球,制备工艺对被包封细胞的生长代谢活性无影响。Fe_3O_4包封率为93%～96%。脉冲电场工艺可实现磁性载细胞微球的高效简便制备。

Technolo(g)y Study on Preparation of Magnetic Fe3O4 Alginate Microcapsules by Pulsed Electric Field Technique

Taking Fe_3O_4 as a magnetic material,sodium alginate andchitosan as a microcapsule prepara- tion materials,the E.coli as cell model and calcium as the cross—linking agent,magnetic microcapsules con- taining cells were prepared by Pulsed Electric Field process.Choosing particle size of microsphere as detec- ting target,the obvious influencing factors were inspected by orthogonal design.The saturation magnetiza- tion of the microcapsules was determined by VSM(Vibrating Sample Magnetometer).The results showed that the concentration of sodium alginate solution was the significant factor impacting on the particle size of magnetic microspheres.In the process condition of Fe_3O_4 concentration lg/L,sodium alginate concentration 10 mg/mL,metal—orifice diameter 450μm,pump speed 4 mL/h,CaCl_2 concentration 20 mg/mL,the super paramagnetic microspheres were prepared with uniform degree of sphericity,good dispensability and strong magnetic response.The average particle size was 132.2μm.Pulsed Electric Field process was simple,conven- ient and feasible,it had no negative effect on the growth and metabolism of cells.The encapsulation efficien- cy of Fe_3O_4 was 93%～96%.