Sharifi-Aghdam Maryam, Faridi-Majidi Reza, Derakhshan Mohammad Ali, Chegeni Arash, Azami Mahmoud
1 Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
2 Medical Devices Bureau, Iranian Food and Drug Administration, Tehran, Iran.
Proc Inst Mech Eng H. 2017 Jul;231(7):652-662. doi: 10.1177/0954411917697751. Epub 2017 Mar 28.
The main objective of this study was to prepare a hybrid three-dimensional scaffold that mimics natural tendon tissues. It has been found that a knitted silk shows good mechanical strength; however, cell growth on the bare silk is not desirable. Hence, electrospun collagen/polyurethane combination was used to cover knitted silk. A series of collagen and polyurethane solutions (4%-7% w/v) in aqueous acetic acid were prepared and electrospun. According to obtained scanning electron microscopy images from pure collagen and polyurethane nanofibers, concentration was set constant at 5% (w/v) for blend solutions of collagen/polyurethane. Afterward, blend solutions with the weight ratios of 75/25, 50/50 and 25/75 were electrospun. Scanning electron microscopy images demonstrated the smooth and uniform morphology for the optimized nanofibers. The least fibers diameter among three weight ratios was found for collagen/polyurethane (25/75) which was 100.86 ± 40 nm and therefore was selected to be electrospun on the knitted silk. Attenuated total reflectance-Fourier transform infrared spectra confirmed the chemical composition of obtained electrospun nanofibers on the knitted silk. Tensile test of the specimens including blend nanofiber, knitted silk and commercial tendon substitute examined and indicated that collagen/polyurethane-coated knitted silk has appropriate mechanical properties as a scaffold for tendon tissue engineering. Then, Alamar Blue assay of the L929 fibroblast cell line seeded on the prepared scaffolds demonstrated appropriate viability of the cells with a significant proliferation on the scaffold containing more collagen content. The results illustrate that the designed structure would be promising for being used as a temporary substitute for tendon repair.
本研究的主要目的是制备一种模拟天然肌腱组织的三维混合支架。已发现针织丝绸具有良好的机械强度；然而，在裸露的丝绸上细胞生长并不理想。因此，采用静电纺丝的胶原蛋白/聚氨酯组合来覆盖针织丝绸。制备了一系列在醋酸水溶液中的胶原蛋白和聚氨酯溶液（4%-7% w/v）并进行静电纺丝。根据从纯胶原蛋白和聚氨酯纳米纤维获得的扫描电子显微镜图像，将胶原蛋白/聚氨酯混合溶液的浓度设定为恒定的5%（w/v）。随后，对重量比为75/25、50/50和25/75的混合溶液进行静电纺丝。扫描电子显微镜图像显示优化后的纳米纤维形态光滑且均匀。在三种重量比中，胶原蛋白/聚氨酯（25/75）的纤维直径最小，为100.86±40纳米，因此被选择用于在针织丝绸上进行静电纺丝。衰减全反射-傅里叶变换红外光谱证实了在针织丝绸上获得的静电纺丝纳米纤维的化学成分。对包括混合纳米纤维、针织丝绸和商业肌腱替代物的样本进行拉伸测试，结果表明胶原蛋白/聚氨酯涂层的针织丝绸作为肌腱组织工程支架具有合适的机械性能。然后，对接种在制备好的支架上的L929成纤维细胞系进行alamar蓝检测，结果表明细胞具有适当的活力，并且在含有更多胶原蛋白的支架上有显著的增殖。结果表明，所设计的结构有望用作肌腱修复的临时替代物。
