Khademolqorani Sanaz, Tavanai Hossein, Chronakis Ioannis S, Boisen Anja, Ajalloueian Fatemeh
Department of Textile Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran.
Department of Textile Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Research Institute for Nanotechnology and Advanced Materials, Isfahan University of Technology, Isfahan 84156-83111, Iran.
Mater Sci Eng C Mater Biol Appl. 2021 Mar;122:111867. doi: 10.1016/j.msec.2021.111867. Epub 2021 Jan 15.
3D scaffolds are in the center of attention for tissue engineering applications. Whilst many studies have focused on the biological properties of scaffolds, less attention has been paid to meeting the biomechanics of the target tissues. In this work, we show how using the same original biomaterial, but different fabrication techniques can lead to a broad range of structural, mechanical, and biological characteristics. Starting with silk fibroin filament as our base biomaterial, we employed electrospinning, film casting, and weft knitting as different scaffold fabrication techniques. Among these three, the weft knit scaffold showed outstanding cell-scaffold interaction including full 3D cell attachment, complete cell coverage around individual filaments, and in-depth cell infiltration. Post-fabrication degumming of silk filament yarns resulted in more bulky and less open pores for the silk fibroin knit scaffold. The decreased pore size after degumming of knit scaffold alleviated the need to in-advance pore filling (a requisite for increasing cell adhesion in a typical knit scaffold having big pores). From a mechanical viewpoint, the weft knit scaffold shows the highest mechanical strength alongside with far better extensibility. Interestingly, the silk filament weft knit scaffold (in the course direction) was 100 and 1000 times more compliant than silk fibroin film and electrospun web, respectively. The observed effect of material type and fabrication technique highlights the suitability of silk fibroin weft-knit scaffolds for the regeneration of load-bearing soft tissues such as urine bladder.
3D支架是组织工程应用的关注焦点。虽然许多研究集中在支架的生物学特性上，但对满足目标组织的生物力学关注较少。在这项工作中，我们展示了使用相同的原始生物材料，但不同的制造技术如何导致广泛的结构、力学和生物学特性。以丝素蛋白长丝作为基础生物材料，我们采用了静电纺丝、流延成膜和纬编作为不同的支架制造技术。在这三种技术中，纬编支架表现出出色的细胞-支架相互作用，包括完全的三维细胞附着、单个细丝周围的完整细胞覆盖以及深入的细胞浸润。丝素蛋白长丝纱线的后处理脱胶导致丝素蛋白针织支架的孔隙更粗大且开孔更少。针织支架脱胶后孔径减小，减轻了预先填充孔隙的需要（这是在具有大孔隙的典型针织支架中增加细胞粘附的必要条件）。从力学角度来看，纬编支架表现出最高的机械强度以及更好的延展性。有趣的是，丝素蛋白长丝纬编支架（在纵向上）分别比丝素蛋白膜和静电纺网柔顺100倍和1000倍。观察到的材料类型和制造技术的影响突出了丝素蛋白纬编支架适用于诸如膀胱等承重软组织的再生。
