Acute ischemic stroke (AIS) is a high mortality cerebrovascular disease associated with vessel curvature. However, the relevant mechanism remains unclear due to a lack of appropriate tortuous vascular models to investigate and validate. This study explores the combination of projection-based 3D bioprinting (PBP) with photo-stimulus-responsive techniques to fabricate a sodium alginate (SA)/acrylamide (AAM) hydrogel vascular scaffold capable of bending deformation. The coordination of Fe3+ ions with carboxylate groups in the alginate chains of the vascular scaffold acts as a molecular switch, which can be dissociated through photoreduction to enable the deformation response. Fourier Transform Infrared (FTIR) and X-ray Photoelectron Spectroscopy (XPS) results verified the deformation principle. By subjecting the scaffold to UV light exposure, Fe3+ is reduced to Fe2+ in spatially selected regions, resulting in the release of strain and subsequent deformation. Furthermore, it also controlled the degree and direction of curvature of the vessels. The cell seeding experiment verified that the vascular scaffold showed excellent biocompatibility. Overall, our approach could be used to generate an in vitro model of curved vascular pathology to investigate the pathogenesis and provide new directions for the diagnosis and treatment of vascular diseases in the future.

中文翻译：

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使用光解离且形态可控的墨水 3D 打印曲折容器。

急性缺血性中风（AIS）是一种与血管弯曲相关的高死亡率脑血管疾病。然而，由于缺乏合适的曲折血管模型来研究和验证，相关机制仍不清楚。本研究探索将基于投影的3D生物打印（PBP）与光刺激响应技术相结合来制造能够弯曲变形的海藻酸钠（SA）/丙烯酰胺（AAM）水凝胶血管支架。Fe3+离子与血管支架的藻酸盐链中的羧酸基团的配位充当分子开关，可以通过光还原解离以实现变形响应。傅里叶变换红外（FTIR）和X射线光电子能谱（XPS）结果验证了变形原理。通过将支架置于紫外线照射下，Fe3+ 在空间选定的区域中被还原为 Fe2+，导致应变释放和随后的变形。此外，它还控制血管的弯曲程度和方向。细胞接种实验验证了血管支架表现出良好的生物相容性。总的来说，我们的方法可用于生成弯曲血管病理学的体外模型，以研究发病机制，并为未来血管疾病的诊断和治疗提供新方向。