Ho Chee Meng Benjamin, Mishra Abhinay, Hu Kan, An Jianing, Kim Young-Jin, Yoon Yong-Jin
School of Mechanical & Aerospace Engineering and §Singapore Centre for 3D Printing, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798.
School of Mechanical & Aerospace Engineering and Singapore Centre for 3D Printing, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798.
ACS Biomater Sci Eng. 2017 Oct 9;3(10):2198-2214. doi: 10.1021/acsbiomaterials.7b00438. Epub 2017 Sep 27.
Fabrication of 3D cell scaffolds has gained tremendous attention in recent years because of its applications in tissue engineering and cell biology applications. The success of tissue engineering or cell interactions mainly depends on the fabrication of well-defined microstructures, which ought to be biocompatible for cell proliferation. Femtosecond-laser-based 3D printing is one of the solution candidates that can be used to manufacture 3D tissue scaffolds through computer-aided design (CAD) which can be efficiently engineered to mimic the microenvironment of tissues. UV-based lithography has also been used for constructing the cellular scaffolds but the toxicity of UV light to the cells has prevented its application to the direct patterning of the cells in the scaffold. Although the mask-based lithography has provided a high resolution, it has only enabled 2D patterning not arbitrary 3D printing with design flexibility. Femtosecond-laser-based 3D printing is trending in the area of tissue engineering and cell biology applications due to the formation of well-defined micro- and submicrometer structures via visible and near-infrared (NIR) femtosecond laser pulses, followed by the fabrication of cell scaffold microstructures with a high precision. Laser direct writing and multiphoton polymerization are being used for fabricating the cell scaffolds, The implication of spatial light modulators in the interference lithography to generate the digital hologram will be the future prospective of mask-based lithography. Polyethylene glycol diacrylate (PEG-DA), ormocomp, pentaerythritol tetraacrylate (PETTA) have been fabricated through TPP to generate the cell scaffolds, whereas SU-8 was used to fabricate the microrobots for targeted drug delivery. Well-designed and precisely fabricated 3D cell scaffolds manufactured by femtosecond-laser-based 3D printing can be potentially used for studying cell migration, matrix invasion and nuclear stiffness to determine stage of cancer and will open broader horizons in the future in tissue engineering and biology applications.
近年来，3D细胞支架的制造因其在组织工程和细胞生物学应用中的用途而备受关注。组织工程或细胞相互作用的成功主要取决于制造明确的微观结构，这些微观结构应该具有生物相容性以促进细胞增殖。基于飞秒激光的3D打印是可用于通过计算机辅助设计（CAD）制造3D组织支架的候选解决方案之一，通过CAD可以有效地设计以模拟组织的微环境。基于紫外线的光刻技术也已用于构建细胞支架，但紫外线对细胞的毒性阻碍了其在支架中细胞直接图案化的应用。尽管基于掩模的光刻技术提供了高分辨率，但它仅能实现二维图案化，而无法进行具有设计灵活性的任意3D打印。基于飞秒激光的3D打印在组织工程和细胞生物学应用领域正成为趋势，这是因为通过可见光和近红外（NIR）飞秒激光脉冲可形成明确的微米和亚微米结构，随后可高精度制造细胞支架微观结构。激光直写和多光子聚合正用于制造细胞支架，空间光调制器在干涉光刻中用于生成数字全息图将是基于掩模光刻的未来发展方向。聚乙二醇二丙烯酸酯（PEG-DA）、有机化合物、季戊四醇四丙烯酸酯（PETTA）已通过双光子聚合制造以生成细胞支架，而SU-8则用于制造用于靶向药物递送的微型机器人。通过基于飞秒激光的3D打印精心设计和精确制造的3D细胞支架可潜在地用于研究细胞迁移、基质侵袭和核硬度以确定癌症阶段，并将在未来组织工程和生物学应用中开辟更广阔的前景。
