Highley Christopher B, Song Kwang Hoon, Daly Andrew C, Burdick Jason A
Department of Bioengineering University of Pennsylvania 210 South 33rd Street Philadelphia PA 19104 USA.
Adv Sci (Weinh). 2018 Oct 24;6(1):1801076. doi: 10.1002/advs.201801076. eCollection 2019 Jan 9.
3D printing involves the development of inks that exhibit the requisite properties for both printing and the intended application. In bioprinting, these inks are often hydrogels with controlled rheological properties that can be stabilized after deposition. Here, an alternate approach is developed where the ink is composed exclusively of jammed microgels, which are designed to incorporate a range of properties through microgel design (e.g., composition, size) and through the mixing of microgels. The jammed microgel inks are shear-thinning to permit flow and rapidly recover upon deposition, including on surfaces or when deposited in 3D within hydrogel supports, and can be further stabilized with secondary cross-linking. This platform allows the use of microgels engineered from various materials (e.g., thiol-ene cross-linked hyaluronic acid (HA), photo-cross-linked poly(ethylene glycol), thermo-sensitive agarose) and that incorporate cells, where the jamming process and printing do not decrease cell viability. The versatility of this particle-based approach opens up numerous potential biomedical applications through the printing of a more diverse set of inks.
3D打印涉及开发具有打印和预期应用所需特性的墨水。在生物打印中，这些墨水通常是具有可控流变特性的水凝胶，沉积后可以稳定下来。在此，开发了一种替代方法，其中墨水仅由堆积微凝胶组成，这些微凝胶旨在通过微凝胶设计（例如组成、尺寸）以及微凝胶的混合来整合一系列特性。堆积微凝胶墨水具有剪切变稀特性，以便于流动，并在沉积后迅速恢复，包括在表面上或沉积在水凝胶支架内的三维空间中时，并且可以通过二次交联进一步稳定。该平台允许使用由各种材料（例如硫醇-烯交联透明质酸（HA）、光交联聚乙二醇、热敏琼脂糖）制成并包含细胞的微凝胶，其中堆积过程和打印不会降低细胞活力。这种基于颗粒的方法的多功能性通过打印更多种类的墨水开辟了众多潜在的生物医学应用。
