双乳液滴电控破裂机制及其在微纤维可控裁剪中的应用研究

In vitro construction of functional tissue and organ for animal-alternative experiments is the frontier of tissue engineering techniques. However, it is a bottleneck problem to construct a kind of biological scaffold with good simulation due to the complexity of the environment and the structure of organism. The three-dimensional hydrogel matrix with microfiber structure, which has good biocompatibility and structural plasticity, is expected to be a breakthrough in biological tissue scaffolds. As such, this project intends to use droplet-based microfluidic technology to study the rapid generation of bamboo-type microfibers with double-emulsion droplets encapsulated, and then to control the rupturing behavior of the double-emulsion droplets in the node by using the alternating current(AC) electric field to realize the controllable cutting of the microfibers. We first investigate the regularity of the double-emulsion droplets encapsulated in the microfibers with controllable spacing, and analyze the main influence factors. Secondly, the mechanism of the deformation and rupturing of double-emulsion drops under confined space is studied by using AC electric field as the regulatory tool, and the rule of electro-controlled rupturing of double-emulsion droplets is explored. Also, the impact forces of rupturing are evaluated. Finally, the experimental study of the electro-controlled rupturing of double-emulsions droplets as a "micro-scissors" in cutting bamboo-type microfibers was developed to achieve the goal of flexible and controllable cutting of microfibers. This project will provide important technical support for the construction of three-dimensional scaffolds in tissue engineering, and has significant clinical application value.

离体构建功能化的组织和器官用于代替动物实验，是组织工程学的前沿技术。但由于生物体内环境以及结构形态的复杂性，构建具有良好模拟性的类生物组织支架一直是困扰该领域的瓶颈问题。具有微纤维结构的三维水凝胶基质，具备良好的生物亲和性与结构可塑性，有望在生物组织支架方面获得突破。为此，本项目拟利用液滴微流控技术研究包裹双乳液滴的竹节型微纤维快速生成，并利用交流电场调控节点处双乳液滴的破裂行为，实现微纤维结构的可控裁剪。首先，研究双乳液滴在微纤维中间距可控的包裹规律，分析其主要影响因素；其次，以交流电场为调控工具，开展受限空间束缚下双乳液滴受力形变及破裂的机制分析，探究双乳液滴电控破裂的规律，并对破裂产生的冲击力进行评估；最后，开展双乳液滴电控破裂作为“微剪刀”在竹节型微纤维裁剪中的实验研究，实现微纤维灵活可控裁剪的目标。本项目将为组织工程学中三维组织支架的构建提供重要技术支撑，具有显著的临床应用价值。

具有微纤维结构的三维水凝胶基质，具备良好的生物亲和性与结构可塑性，有望在离体构建功能化的生物组织支架方面获得突破。为此，本项目利用液滴微流控技术研究了包裹双乳液滴的竹节型微纤维快速生成，并利用交流电场调控节点处双乳液滴的破裂行为，实现了水凝胶微纤维结构的可控裁剪。首先，研究了双乳液滴在微纤维中间距可控的包裹规律，掌握了其主要影响因素；其次，以交流电场为调控工具，开展了受限空间束缚下双乳液滴受力形变及破裂的机制分析，探明了双乳液滴电控破裂的规律；最后，开展了双乳液滴电控破裂作为“微剪刀”在竹节型微纤维裁剪中的实验研究，实现了定长微纤维灵活可控裁剪的目标。作为拓展，本项目还研究了电压、频率、电导率和油相粘度等因素与液滴破裂的时间相关性，实现了由壳厚和电导率控制的两种包裹液滴内封装物的选择性释放。本项目将为组织工程学中三维组织支架的构建提供重要技术支撑，具有显著的临床应用价值。