磁性载细胞海藻酸盐微胶囊的制备及性能研究

【作者】 刘萍；

【导师】 薛伟明；

【作者基本信息】 西北大学 ， 化学工艺， 2008， 硕士

【摘要】 本文以细胞固定化培养为研究背景,开展对载磁壳聚糖-海藻酸盐微球制备的研究。采用脉冲电场工艺制备载磁微球,克服了传统工艺繁琐、操作复杂、大量有机溶剂残留的弊端。鉴于天然多糖海藻酸钠和壳聚糖都具有良好的生物相容性和生物降解性,而且价格低廉、易于工业化生产,实验将它们作为磁性微球的载体材料。首先以微球粒径为检测指标,采用脉冲电场法制备载磁海藻酸钙微球;在此基础上,以微球膜膨胀率为评价参数,进行了成膜工艺的研究。通过系列单因素实验及正交实验,得到以下重要结论:1.制备了平均粒径200μm的载磁微球,微球球形度优良、在水中分散性好、具有强磁响应性。2.载磁海藻酸钙微球的制备因素中,Fe₃O₄浓度、海藻酸钠浓度、锐孔孔径、溶液滴出速度四因素与微球粒径均呈正向相关。CaCl₂浓度与微球粒径均呈负相关。海藻酸钠浓度对粒径影响显著,但浓度过低时不能形成完整微球。实验采用海藻酸钠浓度10～50g/L。Fe₃O₄浓度、CaCl₂浓度、溶液滴出速度为次要影响因素。3.载磁海藻酸钙微球的正交实验结果表明,在Fe₃O₄浓度为1g/L、海藻酸钠浓度为10g/L、采用600μm内径的金属锐孔、溶液滴出速度为4mL/h、CaCl₂浓度为20g/L的工艺条件下,可制备出形态好、粒径小的微球。其中,海藻酸盐浓度为显著影响因素。4.微球的成膜工艺各因素中,采用浓度为1g/L、分子量为5万的壳聚糖,成膜20min的条件下,可制备出膜稳定性最好的载磁壳聚糖-海藻酸钙微球。5.制备工艺对被包封细胞的生长代谢活性无影响。Fe₃O₄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。更多还原

【Abstract】 The thesis aims the immobilized cells as the study background and carries out the preparation of micro-reactor based chitosan- alginate microcapsule with Fe₃O₄.Compared with the preparation of microcapsule by traditional technology,such as the complexity of technology and residual of large organic solven,the technology of pulse electric field has many good characters.considering the characters of biocompatibility、biodegradability、lower price and easier industrialization for chitosan and sodium alginate,we choose them as the materials of magnetic microcapsules.Firstly,the diameter of magnetic microcapsules was chosen as judge criteria.We prepared the sodium alginate magnetic microsphere using the technology of pulse electric field.Then,the study of membrane technics was carried out by testing the swelling ratio of membrane.The following conclusions were made through the single factor tests and orthogonal tests:1.Mean diameter of magnetic microspheres prepared in the experiment was about 200μm.It also has good degree of sphericity,excellent dispersibility in the water and good magnetic responsibility.2.Among factors of the preparation of magnetic alginate microsphere,the concerntration of Fe₃O₄ and alginate,the size of orifice,pump speed assumed a positive interaction with alginate diameter,while the concerntration of CaCl₂ assumed a positive interaction with alginate diameter.The concerntration of alginate was the most remarkable factor.However,the lower concerntation of alginate failed to prepare the microsphere.The change of microsphere diameter was steady with the following preparation conditions:Alginate concerntration—10～50 mg/mL.The pump speed and the concerntration of Fe₃O₄ and CaCl₂ were not remarkable factors.3.The orthogonal tests indicated that the magnetic alginate microspheres of good shape and small diameter could be prepared in the following conditions:the concerntration of Fe₃O₄ - 1g/L,the concerntration of alginate-10g/L,the size of orifice-600μm,the concerntration CaCl₂-20 g/L,among them,the concerntration of alginate was the most remarkable factor. 4.The microsphere membrane was most steady when the moleaular weight of chitotosan were 20000 dalton and 50000 dalton and the concertration of chitosan was 1 mg/mL.5.The Pulsed Electric Field process was simple,convenient and feasible,and it had no negative effect on the growth and metabolism of cells.The encapsulation efficiency of Fe₃O₄ was 93%～96%.更多还原