体外软弹性大鼠胃仿生消化系统的优化研究

In vitro stomach digestion track model system facilitates greatly on the research on animal physiology, food and orally administrated drugs. However, the systems developed so far to maturity are mainly of rigid vessels, which lack of kind of motility that a biological system provides. The delivery of gastric fluid is also through one rigid tube into each vessel representing one sector of the digestion track hence the kind of mixing with the ‘food’ is also quite different from reality. This is much like a conventional chemical reactor. In the current project, we aim at researching on how to optimize a new in vitro rat stomach model to improve its material mixing characters and mixing efficiency to match that measured in vivo. A comparison between the tube (or a few tubes) insert to deliver the gastric fluid into the stomach and a new kind of infusion secretion approach, for achieving digestion reactions, will be carried out. The pulsatile movement will be realized by implementing some specific mechanisms. The non-homogeneous fluid movement inside the system will be investigated through techniques like laser PIV. Transparent silicon material (soft and elastic) will be used to construct the stomach reactor(s). Locally extracted samples will be analyzed to investigate the distribution of the materials during mixing and reaction. All these works will help considerably improving the rat stomach model to make it much more reliable and more realistic. The experiences gained in this work will also provide a good foundation to the development the animal digestion track models as desired by practice.

体外胃仿生消化系统对于研究胃的生理功能和食品、口服药物等消化具有十分重要的作用。 然而，刚性单反应器在模仿胃的运动和研磨功能方面具有较大的缺陷，而现有的动态体外胃仿生消化系统均以管式输送消化液，并且其简单的构型容易造成固体物料的排空顺序和研磨程度与体内有较大的差异。本项目拟对新型动态体外大鼠胃仿生消化系统进行研究构建并优化，包括通过比较管式分泌和弥漫式分泌对大鼠胃内物料混合效率和传质效率的影响，优化胃液的分泌方式；引入变频电动夹爪系统，通过控制幽门的闭合在胃窦内制造回退流，研究回退流的形成机制，探究影响胃窦内流场结构和对固态物料颗粒研磨效果的因素，推动消化机理研究的发展。采用较为透明的硅胶材料制模进行流体PIV实验，并通过局部提取流体样品对其内部的浓度场和速度场变化规律进行研究，进而指导体外大鼠胃仿生消化系统的改进，开发更为科学可靠的体外消化科研平台。

体外胃仿生消化系统对于研究胃的生理功能及食品、口服药物等在胃肠道内消化过程和机理具有十分重要的作用。本项目对新型动态体外仿生大鼠胃消化系统进行了构建、改进、优化和应用。应用3D打印技术制作硅胶鼠胃模型，以替代前期纯手工制作模式，极大地提高了模型制作效率和精度。考察了模拟胃液管的数量、单根胃液分泌管的位置、胃液的分泌模式对酪蛋白悬浮液颗粒在体外仿生鼠胃内混合和消化效率的影响，结果表明当单根胃液分泌管位于腺胃滚动挤压位置时，酪蛋白的消化效率最高。引入了变频电动夹爪系统，通过控制幽门的闭合（频率）在胃窦内实现了回退流。探究了胃内流场对固态物料颗粒移动轨迹的研究，推动了消化机理研究。采用了半透明的硅胶材料制作鼠胃模型以便于进行流场观察。以不同粘度的CMC溶液作为模型食物流体，通过记录一个大颗粒（胡萝卜丁）在鼠胃内运动的轨迹，进一步了解了流场对食物消化过程的影响。最后本项目开展了一系列的应用研究，进一步验证了仿生鼠胃消化系统的可靠性。本项目为建立更科学可靠的体外仿生消化科研平台建立了坚实的基础。