The objective of this study was to evaluate the utility of gelatin-norbornene (GelNB), which is cross-linkable via thiol-ene click chemistry, and the photoinitiator lithium phenyl-2,4,6 trimethylbenzoylphosphinate (LAP) for 3D bioprinting. These materials were compared to two widely used materials, gelatin-methacryloyl (GelMA) and 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (I2959). Characterization of photocuring kinetics revealed that LAP markedly improved the kinetics compared to I2959, which improved stability and print fidelity. Additionally, GelNB exhibited improved photocuring kinetics, improved stability, and decreased filament spreading compared to GelMA. However, inks containing GelMA yielded at lower stress, were more easily extruded, and produced smoother filaments. NIH 3T3 fibroblasts exhibited high viability in printed constructs, regardless of the gelatin derivative or photoinitiator used. Overall, these results support the selection of LAP over I2959 and suggest that GelNB could be a useful alternative to GelMA, although further work is needed to optimize GelNB extrusion.

中文翻译：

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用于三维挤出生物打印的可光交联的明胶衍生物和引发剂的比较。

这项研究的目的是评估明胶-降冰片烯（GelNB）的实用性，它可通过硫醇-烯点击化学进行交联，并使用光引发剂苯基-2,4,6三甲基苯甲酰基次膦酸锂（LAP）进行3D生物打印。将这些材料与两种广泛使用的材料，明胶-甲基丙烯酰基（GelMA）和2-羟基-4'-（2-羟基乙氧基）-2-甲基苯乙酮（I2959）进行了比较。光固化动力学的表征表明，与I2959相比，LAP显着改善了动力学，从而提高了稳定性和印刷保真度。另外，与GelMA相比，GelNB表现出改善的光固化动力学，改善的稳定性和减少的细丝铺展。但是，含有GelMA的油墨在较低的应力下屈服，更容易挤出，并产生更光滑的长丝。无论使用何种明胶衍生物或光引发剂，NIH 3T3成纤维细胞在印刷结构中均具有较高的生存能力。总体而言，这些结果支持选择I2959上的LAP，并表明GelNB可能是GelMA的有用替代品，尽管需要进一步的工作来优化GelNB的挤出。