Wu Yen-Lin, D'Amato Anthony R, Yan Alice M, Wang Richard Q, Ding Xiaochu, Wang Yadong
Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York 14853-0001, United States.
Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853-0001, United States.
ACS Appl Bio Mater. 2020 Nov 16;3(11):7575-7588. doi: 10.1021/acsabm.0c00804. Epub 2020 Oct 26.
Digital light processing (DLP)-based three-dimensional (3D) printing offers large improvements in fabrication throughput and spatial resolution when compared to various other additive manufacturing techniques. Both properties are highly desirable when fabricating biomaterial scaffolds that require design precision. Poly(glycerol sebacate) acrylate (PGSA) is a degradable, biocompatible, and photocurable elastomer. In this work, PGSA ink was developed for DLP 3D printing of porous tubular structures. Ink formulations with varying prepolymer concentrations (10-60 wt %), diluent (dimethyl sulfoxide (DMSO), 2-butoxyethyl acetate (EGBEA), and 1:1 DMSO/EGBEA), and degree of PGSA acrylation (17-75%) were studied to optimize printing efficiency and bulk properties of the printed scaffolds. Prepolymer inks with viscosity (<5 Pa·s) and photopolymerization kinetics (exposure time <10 s) appropriate for DLP were developed. Photocrosslinked PGSA scaffolds were further exposed to postfabrication treatments including additional UV exposure or thermal curing (150 °C) to demonstrate tunability in scaffold degradation kinetics and mechanical properties. Complementary to this effort, a 3D model-generation tool was developed to enable user-friendly customization of tubular scaffold design by controlling the pore and strut size of the volumetric mesh. The resulting DLP-printed PGSA scaffolds present high mimicry to complex 3D models with a minimum feature thickness of 80 μm. The tunable properties of PGSA coupled with enhanced precision in microstructure geometry provide a fabrication platform for a variety of tissue regeneration applications.
与其他各种增材制造技术相比，基于数字光处理（DLP）的三维（3D）打印在制造通量和空间分辨率方面有了很大改进。在制造需要设计精度的生物材料支架时，这两个特性都是非常理想的。聚癸二酸甘油酯丙烯酸酯（PGSA）是一种可降解、生物相容且可光固化的弹性体。在这项工作中，开发了用于DLP 3D打印多孔管状结构的PGSA墨水。研究了具有不同预聚物浓度（10 - 60 wt%）、稀释剂（二甲基亚砜（DMSO）、乙酸2 - 丁氧基乙酯（EGBEA）以及1:1 DMSO/EGBEA）和PGSA丙烯酸化程度（17 - 75%）的墨水配方，以优化打印效率和打印支架的整体性能。开发了具有适合DLP的粘度（<5 Pa·s）和光聚合动力学（曝光时间<10 s）的预聚物墨水。光交联的PGSA支架进一步接受后处理，包括额外的紫外线照射或热固化（150°C），以证明支架降解动力学和机械性能的可调性。与此工作相辅相成的是，开发了一种3D模型生成工具，通过控制体积网格的孔隙和支柱尺寸，实现对管状支架设计的用户友好型定制。由此产生的DLP打印PGSA支架高度模仿复杂的3D模型，最小特征厚度为80μm。PGSA的可调特性以及微观结构几何形状精度的提高，为各种组织再生应用提供了一个制造平台。
