Collaborative Research: Electrowetting Micro Array Printing System for Bioactive Tissue Construct Manufacturing

本合作研究项目的目的是研究电介质上的电润湿过程作为组织工程的先进制造技术。基于电润湿的微流体阵列打印系统将用于快速打印壳聚糖水凝胶和其他生物材料，以构建具有预定义结构、细胞和生长因子的微孔支架。该项目解决了水凝胶、活细胞和生长因子的生物相容性分配的基本挑战，以模拟组织细胞外基质结构并支持细胞增殖。具体来说，研究人员将：(1)从机械强度、流变性、凝固性、可制造性、生物相容性和支持细胞增殖的能力等方面对壳聚糖水凝胶进行表征；(2)建立模型，设计并演示通过电润湿从片上储层生成亚纳升水凝胶液滴，解决生物相容性和液滴分配问题；(3)展示并表征了一个智能系统的无菌性、生物相容性和制造精度，该系统包括软件控制、驱动、多个存储库和打印阵列，以基于心肌组织的计算机辅助设计模型制造支架。如果成功，该项目将使组织工程师能够优化软组织工程支架的机械、运输、材料和生物特性，并具有一定程度的结构控制、精细分辨率（10微米）和嵌入细胞和生长因子。在这个项目中，将对一批研究生和本科生进行先进制造技术和组织工程方面的培训。将建立几个基于项目的学习模块，以加强本科机械和生物医学工程课程。该项目还将用于为当地高中和社区大学学生（包括许多代表性不足的少数民族学生）举办的外展讲习班，以展示高科技机械和电气工程在生物技术方面的应用。

The objective of this collaborative research project is to investigate the process of electrowetting on dielectric as an advanced manufacturing technology for tissue engineering. An electrowetting-based microfluidics array printing system will be created to rapidly print chitosan hydrogel and other biomaterials to build micro porous scaffolds with predefined structures, cells, and growth factors. The project addresses fundamental challenges to biocompatible dispensing of hydrogels, living cells, and growth factors, to mimic tissue extra cellular matrix architecture and support cell proliferation. Specifically, the investigators will: (1) characterize chitosan hydrogel, in terms of its mechanical strength, rheology, solidification, manufacturability, biocompatibility, and ability to support cell proliferation; (2) model, design, and demonstrate the generation of sub-nanoliter hydrogel droplets from an on-chip reservoir through electrowetting, addressing issues of biocompatibility and droplet dispensing; and (3) demonstrate and characterize the sterility, biocompatibility, and manufacturing precision of an intelligent system including software control, actuation, multiple reservoirs, and printing arrays, to manufacture scaffolds based on a computer-aided design model of myocardial tissue. If successful, this project will enable tissue engineers to optimize mechanical, transport, material, and biological properties of a soft tissue engineering scaffold, with a degree of structural control, fine resolution (10 microns) and embedded cells and growth factors not currently available. In this project, a group of graduate and undergraduate senior students will be trained in advanced manufacturing technology and tissue engineering. Several project-based learning modules will be created to strengthen the undergraduate mechanical and biomedical engineering curricula. The project will also be used in outreach workshops for local high school and community college students, including many underrepresented minority students, to showcase high-tech mechanical and electrical engineering applications in biotechnology.