Cell survival during the early stages of transplantation and before new blood vessels formation is a major challenge in translational applications of 3D bioprinted tissues. Supplementing oxygen (O₂) to transplanted cells via an O₂ generating source such as calcium peroxide (CPO) is an attractive approach to ensure cell viability. Calcium peroxide also produces calcium hydroxide that reduces the viscosity of bioinks, which is a limiting factor for bioprinting. Therefore, adapting this solution into 3D bioprinting is of significant importance. In this study, a gelatin methacryloyl (GelMA) bioink that is optimized in terms of pH and viscosity is developed. The improved rheological properties lead to the production of a robust bioink suitable for 3D bioprinting and controlled O₂ release. In addition, O₂ release, bioprinting conditions, and mechanical performance of hydrogels having different CPO concentrations are characterized. As a proof of concept study, fibroblasts and cardiomyocytes are bioprinted using CPO containing GelMA bioink. Viability and metabolic activity of printed cells are checked after 7 days of culture under hypoxic condition. The results show that the addition of CPO improves the metabolic activity and viability of cells in bioprinted constructs under hypoxic condition.

中文翻译：

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含氧细胞的明胶甲基丙烯酰结构的 3D 生物打印。

在移植的早期阶段和新血管形成之前的细胞存活是 3D 生物打印组织转化应用的主要挑战。通过过氧化钙 (CPO) 等O ₂生成源为移植细胞补充氧气 (O ₂ )是确保细胞活力的一种有吸引力的方法。过氧化钙还会产生氢氧化钙，降低生物墨水的粘度，这是生物打印的限制因素。因此，将此解决方案应用于 3D 生物打印具有重要意义。在这项研究中，开发了一种在 pH 值和粘度方面进行优化的明胶甲基丙烯酰 (GelMA) 生物墨水。改进的流变特性导致生产适用于 3D 生物打印和受控 O₂释放。此外，还表征了具有不同 CPO 浓度的水凝胶的O ₂释放、生物打印条件和机械性能。作为概念研究的证明，成纤维细胞和心肌细胞使用含有 GelMA 生物墨水的 CPO 进行生物打印。在缺氧条件下培养 7 天后，检查打印细胞的活力和代谢活性。结果表明，在缺氧条件下，CPO的加入提高了生物打印构建体中细胞的代谢活性和活力。