Design and fabrication of structured microfibers for the development of biomimetic tissues

在复杂的横截面结构中塑造多种材料将为组织工程提供许多优势，例如精确控制不同生物材料的位置和相互作用，从而增加细胞的增殖和分化。此外，在结构横截面上的多材料排列将导致模仿用于药物筛选的器官芯片模型中生物组织的分层结构。然而，目前的制造技术面临着在复杂形状中结合多种材料的挑战。在这个项目中，我们将提出一种用于制造结构微纤维的超纤维技术，其中多种材料组织在复杂的横截面结构中。通过将四种前驱体溶液通过3D打印的微流体装置共流动，并在紫外线照射下固化，将制备出结构微纤维。该项目的目标是通过定制微流体装置的设计和前驱体溶液的流速来设计微纤维的横截面结构，从而建立材料相互作用的不同组合和集成区域。首先，微流控装置将设计成在同心、堆叠、i型、t型、三明治、圆芯、多芯和多芯等八种截面结构中对多种材料进行成型。其次，通过聚合物溶液、溶剂和光引发剂的不同组成来制备聚合物前驱体溶液，并确定材料的性能。第三，对微流控器件进行3D打印，建立实验装置，制备不同截面的微纤维。优化实验条件，制备均匀和非均匀截面结构的超细纤维。该项目的最终目标是通过3D打印微流体装置实现控制制造特定截面结构的超纤维的策略。本项目完成后，我们将对其进行扩展，制作体外组织模型，作为药物筛选的器官芯片模型。

Shaping multiple materials in complex cross-sectional structures will provide numerous advantages in tissue engineering, such as precise control over the position, and interaction of different biomaterials, which will result in increasing the proliferation, and differentiation of cells. Moreover, multi-material arrangement in structured cross-sections will result in mimicking the hierarchical architecture of biological tissues in the organ-on-chip models for drug screening. However, the current fabrication technology face challenges in incorporating multiple materials in complex shapes. In this project, we will propose a microfiber technology for the fabrication of structured microfibers, with multiple materials organized in complex cross-sectional structures. By coflowing four precursor solutions through 3D printed microfluidic devices and curing them with UV exposure, the structured microfibers will be fabricated. The aim of this project will be to engineer the cross-sectional structures of microfibers by tailoring the design of microfluidic devices and the flow rate of precursor solutions in such a way that different combinations and integration areas of material interactions can be established. Firstly, microfluidic devices will be designed to shape multiple materials in eight cross-sectional structures, including concentric, stacked, I-shaped, T-shaped, sandwich, circular-core, multiple-cores, and plus-core cross-sections. Secondly, the polymer precursor solutions will be prepared by varying compositions of polymer solutions, solvent and photo-initiator and the material properties will be determined. Thirdly, the microfluidic devices will be 3D printed and the experimental setup will be established to fabricate microfibers with different cross-sections. The experimental conditions will be optimized to fabricate microfiber in uniform and non-uniform cross-sectional structures. The end goal of this project will be to realize a strategy for the controlled fabrication of a specific cross-sectional structure of microfiber through the 3D printed microfluidic device. After the completion of this project, we will be expanding it for the fabrication of in-vitro tissue models which will serve as organ-on-chip models for drug screening.