Purpose

This study aimed to develop personalized biodegradable stent (BDS) for the treatment of coronary heart disease. Three-dimensional (3D) printing technique has offered easy and fast fabrication of BDS with enhanced reproducibility and efficacy.

Methods

A variety of BDS were printed with 3 types of hydrogel (~5 ml) resources (10%w/v sodium alginate (SA), 10%w/v cysteine-sodium alginate (SA-CYS), and 10%w/v cysteine-sodium alginate with 0.4%w/v PLA-nanofibers (SA-CYS-NF)) dispersed from an 22G print head nozzle attached to the BD-syringe. The printability of hydrogels into 3D structures was examined based on such variables as hydrogel’s viscosity, printing distance, printing speed and the nozzle size.

Results

It was demonstrated that alginate composition (10%w/v) offered BDS with sufficient viscosity that defined the thickness and swelling ratio of the stent struts. The thickness of the strut was found to be 338.7 ± 29.3 μm, 262.5 ± 14.7 μm and 237.1 ± 14.7 μm for stents made of SA, SA-CYS and SA-CYS-NF, respectively. SA-CYS-NF stent displayed the highest swelling ratio of 38.8 ± 2.9% at the initial 30 min, whereas stents made of SA and SA-CYS had 23.1 ± 2.4% and 22.0 ± 2.4%, respectively.

Conclusion

The printed stents had sufficient mechanical strength and were stable against pseudo-physiological wall shear stress. An addition of nanofibers to alginate hydrogel significantly enhanced the biodegradation rates of the stents. In vitro cell culture studies revealed that stents had no cytotoxic effects on human umbilical vein endothelial cells (HUVECs) and Raw 264.7 cells (i.e., Monocyte/macrophage-like cells), supporting that stents are biocompatible and can be explored for future clinical applications.

中文翻译：

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3D 打印水凝胶心血管支架的参数优化

目的

本研究旨在开发用于治疗冠心病的个性化生物可降解支架（BDS）。三维 (3D) 打印技术提供了简单快速的 BDS 制造，具有增强的再现性和功效。

方法

各种 BDS 印有 3 种类型的水凝胶（~5 ml）资源（10% w / v海藻酸钠 (SA)、10% w / v半胱氨酸-海藻酸钠 (SA-CYS) 和 10%w/v半胱氨酸-海藻酸钠与 0.4% w/v PLA-纳米纤维 (SA-CYS-NF)) 从连接到 BD 注射器的 22G 打印头喷嘴分散。根据水凝胶的粘度、打印距离、打印速度和喷嘴尺寸等变量，检查了水凝胶在 3D 结构中的可打印性。

结果

已证明藻酸盐组合物 (10% w / v ) 为 BDS 提供了足够的粘度，其定义了支架支柱的厚度和溶胀率。对于由 SA、SA-CYS 和 SA-CYS-NF 制成的支架，发现支柱的厚度分别为 338.7 ± 29.3 μm、262.5 ± 14.7 μm 和 237.1 ± 14.7 μm。SA-CYS-NF 支架在最初 30 分钟显示出最高的膨胀率，为 38.8±2.9%，而 SA 和 SA-CYS 支架分别为 23.1±2.4% 和 22.0±2.4%。

结论

打印的支架具有足够的机械强度，并且对假生理壁剪切应力是稳定的。在藻酸盐水凝胶中添加纳米纤维显着提高了支架的生物降解率。体外细胞培养研究表明，支架对人脐静脉内皮细胞 (HUVEC) 和 Raw 264.7 细胞（即单核细胞/巨噬细胞样细胞）没有细胞毒性作用，支​​持支架具有生物相容性，可用于未来的临床应用。