Department of Biomedical Engineering, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510006, China.
National Engineering Research Center for Tissue Restoration and Reconstruction (NERC-TRR), Guangzhou 510006, China.
ACS Biomater Sci Eng. 2021 Oct 11;7(10):4971-4981. doi: 10.1021/acsbiomaterials.1c00980. Epub 2021 Sep 10.
Simulating the structure and function of blood capillaries is very important for an in-depth insight into their role in the human body and treatment of capillary-related diseases. Due to the similar composition and structure, hollow hydrogel microfibers are well-recognized as potential biomimetic blood capillaries. In this paper, we report a novel, facile, and reproducible method to fabricate coaxial microfluidic chips via 3D printing-assisted soft lithography and then hollow hydrogel microfibers using the as-prepared coaxial microfluidic chips. Instead of traditional photoresist-based lithography, 3D printing of gelatin hydrogel under various extrusion pressures is used to construct sacrificial templates of coaxial microfluidic chips. Various solid and hollow hydrogel microfibers with complicated and hierarchical structures can be obtained via multitype coaxial microfluidic chips or a combination of coaxial microfluidic fabrication and post-treatment. The as-formed hollow hydrogel microfibers are evaluated in detail as biomimetic blood capillaries, including physicochemical and cytological properties. Our results prove that the hollow hydrogel microfibers exhibit excellent mass transport capacity, hemocompatibility, semipermeability, and mechanical strength, and their barrier function can be further enhanced in the presence of endothelial cells. Overall, our 3D printing-assisted fabrication strategy provides a new technique to construct microfluidic chips with complicated 3D microchannels, and the resulting hollow hydrogel microfibers are promising candidates for blood capillaries.
模拟血液毛细血管的结构和功能对于深入了解其在人体中的作用以及治疗毛细血管相关疾病非常重要。由于空心水凝胶微纤维具有相似的组成和结构，因此被认为是潜在的仿生血液毛细血管。在本文中，我们报告了一种新颖、简便且可重复的方法，通过 3D 打印辅助软光刻制造同轴微流控芯片，然后使用所制备的同轴微流控芯片来制造空心水凝胶微纤维。我们使用不同挤出压力下的明胶水凝胶 3D 打印来替代传统的基于光致抗蚀剂的光刻技术，构建同轴微流控芯片的牺牲模板。通过多类型同轴微流控芯片或同轴微流控制造和后处理的组合，可以获得具有复杂和分级结构的各种实心和空心水凝胶微纤维。我们详细评估了所形成的空心水凝胶微纤维作为仿生血液毛细血管的性能，包括物理化学和细胞学特性。我们的结果证明，空心水凝胶微纤维具有出色的传质能力、血液相容性、半透性和机械强度，并且在存在内皮细胞的情况下，其屏障功能可以进一步增强。总体而言，我们的 3D 打印辅助制造策略为构建具有复杂 3D 微通道的微流控芯片提供了一种新技术，而所得的空心水凝胶微纤维是血液毛细血管的有前途的候选材料。
