磁响应型微胶囊的合成及其可控释放的研究

发布时间：2018-06-30 06:07

本文选题：磁响应型微胶囊 + 层层组装　；参考：《沈阳工业大学》2015年硕士论文

【摘要】：近年来，响应型微胶囊被广泛应用于表面涂层、防腐材料、光电学、生物医学及药物传输等领域，并在这些领域做出越来越重大的贡献。微胶囊技术发展的最终目标是实现芯材物质在特定的时间、位置按照一定的速率进行可控的释放。但是，目前对于微胶囊释放的调控手段仅限于被动式的渗透释放和破坏式的瞬间释放。本文采用水热法制备均一性良好且尺寸可控的Fe3O4纳米颗粒，并通过类St ber法对Fe3O4进行SiO2的包覆，再通过层层组装的方法将尺寸较小的Fe3O4颗粒嵌于微胶囊的聚电解质囊壁上，将SiO2刻蚀，最终得到了一种中心和囊壁均带有磁性颗粒的磁响应型微胶囊。本文通过调节搅拌前驱体的水浴温度及VEG/VDEG的比值实现了对磁性颗粒大小的调控；改变TMAH的量发现加入1.6mL时最适合TEOS在磁性颗粒表面发生水解，，且改变TEOS的加入量可以实现对微胶囊的装载能力的调控；层层组装法制备微胶囊的过程中，离子强度的增加不利于制备磁响应微胶囊。在微胶囊的可控释放实验中，对比有无外加静磁场的释放曲线发现，80min内，4000G的磁场作用下微胶囊释放了约80%的芯材物质，而无磁场时仅释放41%（4000G磁场下仅需25min）；增大磁场强度至5800G，释放80%的芯材只需37min，且80min时释放量可达96%。对比相同条件下囊壁有无磁性颗粒嵌入的微胶囊的释放曲线发现，在磁场作用下的主动式挤压释放过程中，外磁场对磁性颗粒的吸引作用引起的微胶囊之间的相互挤压起主导作用。以上结果均证明了磁场导致的微胶囊形变及内部压强的改变对芯材物质释放速率的调控性。与以往的微胶囊的释放方式相比，本文的可控释放是一种新型的、调控性更强的主动式挤压释放，且微胶囊的装载空间可调，可重复使用。相对于其它压力挤压方式，磁性颗粒具有良好的生物相容性，且磁力挤压可实现对芯材释放的“远程”（无直接接触）控制，对于在生物体内进行靶向药物传输和药物可控释放更具有实际应用价值。
[Abstract]:In recent years, responsive microcapsules have been widely used in the fields of surface coating, anticorrosive materials, photoelectricity, biomedicine and drug transport, and have made more and more contributions in these fields. The ultimate goal of the development of microencapsulation technology is to realize the controllable release of the core material at a certain time and position at a certain rate. However, the current regulation of microcapsule release is limited to passive osmotic release and destructive instantaneous release. In this paper, Fe _ 3O _ 4 nanoparticles with good homogeneity and controllable size were prepared by hydrothermal method. Fe _ 3O _ 4 particles were coated with Sio _ 2 by St-like ber method, and the smaller Fe _ 3O _ 4 particles were embedded on the wall of microencapsulated polyelectrolyte capsules by layer-by-layer assembly. Finally, a magnetically responsive microcapsule with magnetic particles in the center and the wall of the capsule was obtained by etching the Sio _ 2. In this paper, the size of magnetic particles is controlled by adjusting the water bath temperature of agitated precursor and the ratio of VEGF / VDEG, and it is found that the addition of 1.6 mL of TMAH is most suitable for the hydrolysis of TEOS on the surface of magnetic particles. The loading capacity of microcapsules can be controlled by changing the amount of TEOS, and the increase of ionic strength is not conducive to the preparation of magnetically responsive microcapsules in the process of preparing microcapsules by layer-by-layer assembly. In the controlled release experiment of microcapsules, it was found that the microcapsules released about 80% of the core material under the action of magnetic field within 80 minutes, but only 41% (25min) in the absence of magnetic field, compared with the release curve with or without an external static magnetic field. When the magnetic field intensity is increased to 5800G, it takes only 37 mins to release 80% of the core material, and the release amount can reach 96g at 80min. Comparing the release curves of microcapsules with or without magnetic particles embedded in the wall of the capsule under the same conditions, it is found that in the process of active extrusion release under the action of magnetic field, The external magnetic field plays a leading role in squeezing the microcapsules caused by the attraction of magnetic particles. The above results show that the deformation of microcapsules induced by magnetic field and the change of internal pressure can regulate the release rate of core materials. Compared with the previous release methods of microcapsules, the controlled release in this paper is a new and more controllable active extrusion release, and the loading space of the microcapsules is adjustable and can be reused. Compared with other pressure extrusion methods, magnetic particles have good biocompatibility, and magnetic extrusion can achieve "remote" (no direct contact) control of core release. It has more practical application value for target drug delivery and controlled drug release in vivo.
【学位授予单位】：沈阳工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33;TQ460.1

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