Abstract This work describes development of a silk fibroin (SF)-based ink material for digital light processing 3D printing. Riboflavin initiates the crosslinking of SF molecules under irradiation with visible light to form an SF hydrogel through dityrosine bonding. Rapid formation of a β-sheet structure induces shrinkage of SF hydrogels in phosphate-buffered saline solution at 37 °C. Such shrinkage of SF hydrogel is effectively prevented by addition of gelatin to SF ink. As the ratio of gelatin in the composite ink is increased, the density of β-sheet structures is reduced, and structural deformation of the 3D SF/gelatin hydrogel is inhibited. Printability is critical in fabrication of 3D SF/gelatin composite hydrogel structures. For evaluation of printing performance, the actual width of the hydrogel formed by 3D printing is compared with the designed width. The 3D printing of SF is performed by irradiating a series of features with different shapes or sizes in a vertical manner.

中文翻译：

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明胶对数字光加工 3D 打印制备的丝素蛋白水凝胶结构尺寸稳定性的影响

摘要 这项工作描述了用于数字光处理 3D 打印的基于丝素蛋白 (SF) 的油墨材料的开发。核黄素在可见光照射下引发 SF 分子的交联，通过二酪氨酸键形成 SF 水凝胶。β-折叠结构的快速形成导致 SF 水凝胶在 37°C 磷酸盐缓冲盐溶液中收缩。通过在SF墨水中添加明胶，可以有效防止SF水凝胶的这种收缩。随着复合油墨中明胶比例的增加，β-折叠结构的密度降低，3D SF/明胶水凝胶的结构变形受到抑制。可印刷性对于 3D SF/明胶复合水凝胶结构的制造至关重要。用于评估打印性能，将 3D 打印形成的水凝胶的实际宽度与设计宽度进行比较。SF 的 3D 打印是通过以垂直方式照射一系列具有不同形状或尺寸的特征来执行的。