Shokrollahi Parvin, Garg Piyush, Wulff David, Hui Alex, Phan Chau-Minh, Jones Lyndon
Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, 200 Columbia Street West, Waterloo, ON N2L 3G1, Canada; Centre for Eye and Vision Research (CEVR), 17W Hong Kong Science Park, Hong Kong.
Centre for Ocular Research & Education (CORE), School of Optometry & Vision Science, University of Waterloo, 200 Columbia Street West, Waterloo, ON N2L 3G1, Canada.
Int J Pharm. 2025 Jan 5;668:124999. doi: 10.1016/j.ijpharm.2024.124999. Epub 2024 Nov 23.
3D printing, also known as additive manufacturing, continues to reshape manufacturing paradigms in healthcare by providing customized on-demand object fabrication. However, stereolithography-based 3D printers encounter a conflict between optimizing printing parameters, requiring more time, and print efficiency, requiring less time. Moreover, commonly used metrics to assess shape fidelity of 3D printed hydrogel materials like 'circularity' and 'printability' are limited by the soft nature of hydrogels, that can cause irregularities in their boundary. To unlock the full potential of 3D printing of biomaterials, it is also necessary to understand correlation between printing parameters and ink properties. In this work, a method based on curing depth, overcuring (cumulative cure), and print thickness was developed, which enables a time-efficient and reliable determination of printing conditions for complex geometries using gelatin methacrylate hydrogel biomaterial ink. We also examined the impact of printing direction on the print quality in terms of object/print thickness and aspect ratio. Moreover, the effects of dye concentration, exposure time, and layer thickness on print quality were evaluated, with discussions focused on the correlation between print dimension to layer thickness. Further evaluation was achieved by successfully printing bioinspired corneal stroma-like scaffold and delicate structures like a contact lens and a model eyeball, substantially expanding the scope of this method in producing high-quality prints with intricate details. We also demonstrate the effectiveness of 'Feret ratio,' another measure of object shape, in assessing the shape fidelity of different prints. Overall, the results highlight the practical potential of this method in enhancing the speed and reliability of the 3D printing processes involving complex geometries using a low-cost 3D printers.
3D打印，也称为增材制造，通过提供按需定制的物体制造，继续重塑医疗保健领域的制造模式。然而，基于立体光刻的3D打印机在优化打印参数（需要更多时间）和打印效率（需要更少时间）之间存在冲突。此外，用于评估3D打印水凝胶材料形状保真度的常用指标，如“圆度”和“可打印性”，受到水凝胶柔软性质的限制，这可能导致其边界出现不规则。为了释放生物材料3D打印的全部潜力，还需要了解打印参数与墨水特性之间的相关性。在这项工作中，开发了一种基于固化深度、过度固化（累积固化）和打印厚度的方法，该方法能够使用甲基丙烯酸明胶水凝胶生物材料墨水，高效且可靠地确定复杂几何形状的打印条件。我们还从物体/打印厚度和长宽比的角度研究了打印方向对打印质量的影响。此外，评估了染料浓度、曝光时间和层厚度对打印质量的影响，讨论集中在打印尺寸与层厚度之间的相关性。通过成功打印仿生角膜基质样支架以及隐形眼镜和眼球模型等精细结构，进一步扩大了该方法在生产具有复杂细节的高质量打印品方面的应用范围。我们还证明了“费雷特比率”（另一种物体形状测量方法）在评估不同打印品形状保真度方面的有效性。总体而言，结果突出了该方法在使用低成本3D打印机提高涉及复杂几何形状的3D打印过程的速度和可靠性方面的实际潜力。
