Scalable Laser Printing of Three-Dimensional Living Tissue Constructs

三维活组织结构的可扩展激光打印

• 批准号: 1537956
• 负责人: Yong Huang
• 金额: $ 30万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1537956&HistoricalAwards=false
• 关键词: Scalable; Laser; Printing; Three; Dimensional

The rising success rate of transplants has resulted in a critical need for more tissues and organs. Approximately 95,000 people are on the waiting list for new organs in the US alone, and some die every day waiting for transplants. Organ printing provides a promising solution to the problem of organ donor shortage. This award supports fundamental research to generate knowledge that enables the scale up of a jet-based, orifice-free laser bioprinting technique for organ printing. Results from this research will enable the wider use of laser printing for the fabrication of living tissue constructs for implantation. In addition, this award will promote the development of bioprinting technologies for cell and organ printing and provide three-dimensional engineered tissues for cell behavior and pharmacokinetics studies.In this new laser bioprinting technique, an optical scanner will be incorporated into the laser beam delivery system to optically guide laser pulses to efficiently transfer bioinks of a ribbon instead of mechanically moving the ribbon. The objective of this research is to understand the effects of the interaction of laser pulses-induced adjacent fluid jets on the jettability and printability during optical scanner-enabled laser-induced forward transfer bioprinting. The jettability will be evaluated based on whether two adjacent well-defined jets can be formed during jet formation, and the printability will be assessed based on whether a well-defined line can be formed from well-defined jets. The formation of each laser-induced jet will be modeled using the existing homogenous nucleation-based phase explosion theory. The governing fluid continuity and Navier-Stokes equations for droplet formation under the jet interaction will be solved numerically using a finite element method with mixed interpolation for spatial discretization as well as an implicit finite difference method for time integration. In order to derive a reduced system of equations and boundary conditions containing the governing physics, a scale analysis of the governing equations and interfacial conditions will be performed. The scale analysis results will be used to validate the numerical simulation on the onset of instability (droplet formation) under the effects of two adjacent jets. The resulting knowledge of the interaction of adjacent jets will be used to predict the influences of printing conditions such as the scanning speed of optical scanner on the jettability and printability and further validated during the laser bioprinting of cellular tubes.

移植成功率的不断提高导致对更多组织和器官的迫切需求。仅在美国就有大约 95,000 人在等待新器官的名单上，每天都有一些人在等待移植过程中死亡。器官打印为器官捐献者短缺问题提供了一个有前景的解决方案。该奖项支持基础研究，以产生知识，从而扩大用于器官打印的基于喷射的无孔激光生物打印技术。这项研究的结果将使激光打印能够更广泛地用于制造用于植入的活体组织结构。此外，该奖项还将促进细胞和器官打印生物打印技术的发展，并为细胞行为和药代动力学研究提供三维工程组织。在这种新型激光生物打印技术中，光学扫描仪将被纳入激光束传输系统中，以光学方式引导激光脉冲，从而有效地转移色带的生物墨水，而不是机械移动色带。本研究的目的是了解在光学扫描仪驱动的激光诱导正向转移生物打印过程中，激光脉冲诱导的相邻流体射流的相互作用对可喷射性和可打印性的影响。可喷射性将根据在喷射形成过程中是否可以形成两个相邻的轮廓分明的喷射来评估，而印刷适性将根据是否可以由轮廓分明的喷射形成清晰的线来评估。每个激光诱导射流的形成将使用现有的基于均质成核的相爆炸理论进行建模。射流相互作用下液滴形成的控制流体连续性和纳维-斯托克斯方程将使用有限元方法进行数值求解，该方法具有用于空间离散的混合插值法以及用于时间积分的隐式有限差分法。为了导出包含控制物理场的简化方程组和边界条件，将对控制方程和界面条件进行尺度分析。尺度分析结果将用于验证在两个相邻射流的影响下开始不稳定（液滴形成）的数值模拟。由此产生的相邻喷射相互作用的知识将用于预测打印条件（例如光学扫描仪的扫描速度）对可喷射性和可打印性的影响，并在细胞管的激光生物打印过程中进一步得到验证。