A printing process can enable the flexible and complex design of tissue-specific three-dimensional (3D) micro/macroscale structures. Composite scaffolds printed using bioceramics and various synthetic polymers or natural hydrogels have been previously employed in bone tissue regeneration because of their properties which can compensate for the shortcomings of either ceramic or hydrogel. In particular, the combination of gelatin and hydroxyapatite (HA) fabricated using electrospinning and leaching methods have been applied in bone tissue regeneration due to various mechanical and biological synergistic effects of the composites. However, 3D-printing of the biomimetic composite bioink (gelatin and high weight fraction of bioceramic, ∼ 70 wt%) has been very difficult due to the rheological properties of gelatin which makes them very sensitive to processing conditions, and because of the high wt% of HA in the bioink, HA can be easily sedimented during a printing process, resulting in poor extrusion-ability due to the clogging phenomenon in the nozzle. To solve the problem, in this study, we propose a new type of bioink in which a polyol was employed as a biocompatible processing agent. Various material/processing factors were considered to develop an optimal condition to obtain stable macroscale and mesh-structured gelatin/HA composites. The biocomposites showed outstanding hyperelastic recoverable properties compared to the alginate/HA composite with similar geometrical structure. Using in vitro human adipose stem cells, we observed that the biocomposite performed as a well-organized cell-activating platform for encouraging efficient cellular activities. The proposed bioink formulation and printing process showed great potential for successfully and stably fabricating a biomimetic organic/inorganic composite for hard tissue engineering.

打印过程可以实现组织特定的三维（3D）微观/宏观结构的灵活复杂的设计。使用生物陶瓷和各种合成聚合物或天然水凝胶印刷的复合支架先前已被用于骨组织再生中，这是因为它们的特性可以弥补陶瓷或水凝胶的缺点。特别地，由于复合材料的各种机械和生物协同作用，使用静电纺丝和浸出方法制造的明胶和羟磷灰石（HA）的组合已应用于骨组织再生。但是，仿生复合生物墨水的3D打印（明胶和高重量的生物陶瓷，由于明胶的流变特性使其对加工条件非常敏感，因此约70 wt％是非常困难的。此外，由于生物墨水中HA的wt％高，在印刷过程中HA易于沉淀，导致由于喷嘴中的堵塞现象，导致挤出能力差。为了解决该问题，在这项研究中，我们提出了一种新型的生物墨水，其中多元醇被用作生物相容性处理剂。考虑了各种材料/加工因素以开发最佳条件以获得稳定的宏观和网状明胶/ HA复合材料。与具有相似几何结构的藻酸盐/ HA复合材料相比，该生物复合材料显示出出色的超弹性可恢复特性。使用 HA在打印过程中容易沉淀，由于喷嘴中的堵塞现象，导致挤出能力差。为了解决该问题，在这项研究中，我们提出了一种新型的生物墨水，其中多元醇被用作生物相容性处理剂。考虑了各种材料/加工因素以开发最佳条件以获得稳定的宏观和网状明胶/ HA复合材料。与具有相似几何结构的藻酸盐/ HA复合材料相比，该生物复合材料显示出出色的超弹性可恢复特性。使用 HA在打印过程中很容易沉积，由于喷嘴中的堵塞现象，导致挤出能力差。为了解决该问题，在这项研究中，我们提出了一种新型的生物墨水，其中多元醇被用作生物相容性处理剂。考虑了各种材料/加工因素以开发最佳条件以获得稳定的宏观和网状明胶/ HA复合材料。与具有相似几何结构的藻酸盐/ HA复合材料相比，该生物复合材料显示出出色的超弹性可恢复特性。使用 考虑了各种材料/加工因素以开发最佳条件以获得稳定的宏观和网状明胶/ HA复合材料。与具有相似几何结构的藻酸盐/ HA复合材料相比，该生物复合材料显示出出色的超弹性可恢复特性。使用 考虑了各种材料/加工因素以开发最佳条件以获得稳定的宏观和网状明胶/ HA复合材料。与具有相似几何结构的藻酸盐/ HA复合材料相比，该生物复合材料显示出出色的超弹性可恢复特性。使用在体外人类脂肪干细胞中，我们观察到生物复合物表现为组织良好的细胞活化平台，可促进有效的细胞活动。拟议的生物墨水配方和印刷工艺显示出成功和稳定地制造用于硬组织工程的仿生有机/无机复合材料的巨大潜力。