Chen Qin, Yan Xiaodong, Chen Kai, Feng Cunao, Wang Dagang, Li Xiaowei, Zhao Xiaoduo, Chai Zhimin, Wang Qingliang, Zhang Dekun, Zeng Hongbo
School of Chemical Engineering and Technology, School of Materials Science and Physics, School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou 221116, China.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
J Mater Chem B. 2023 Feb 22;11(8):1713-1724. doi: 10.1039/d2tb02511f.
Hydrogels have attracted much attention as cartilage substitutes due to their human tissue-like characteristics. However, developing cartilage substitutes require the combination of high mechanical strength and low friction. Despite great success in tough hydrogels, this combination was hardly realized. Inspired by the natural cartilage, electrospun fibrous membrane reinforced hydrogels with superior mechanical properties and low friction coefficient were designed using electrospinning, freeze-thawing, and annealing techniques. An ordered fibrous membrane was first constructed by electrospinning, in which the tensile strength and modulus have been improved successfully. Then the PVA/PAA/GO hydrogel was modified layer-by-layer by the multilayer ordered electrospun membrane of PVA/PAA/GO. The ordered fibrous membrane significantly enhanced the mechanical strength and friction properties in a manner that mimicked the collagen fibrils in the cartilage. When the number of the membranes was 4, the mechanical properties of the fibrous membrane reinforced hydrogel is maximized, which can be compared to natural cartilage, which can achieve a tensile strength of 13.7 ± 1.5 MPa, tensile modulus of 27.5 ± 3.2 MPa, compressive strength of 12.32 ± 1.35 MPa, compressive modulus of 20.35 ± 2.50 MPa. The ordered fibrous membrane endows the hydrogel with a higher tearing energy of 39.16 ± 4.05 KJ m, which is the 5 times that of pure hydrogel (7.74 ± 0.86 KJ m). In addition, the friction coefficient of the fibrous membrane reinforced hydrogel is as low as 0.039, 2 times smaller than that of the hydrogel without addition of the fibrous membrane. Therefore, such hydrogels had excellent mechanical properties and tribological properties, which could be widely used in tissue engineering such as in cartilage replacement.
水凝胶因其类似人体组织的特性，作为软骨替代物备受关注。然而，开发软骨替代物需要兼具高机械强度和低摩擦性能。尽管在制备坚韧水凝胶方面取得了巨大成功，但这种组合却很难实现。受天然软骨启发，利用静电纺丝、冻融和退火技术设计了具有优异机械性能和低摩擦系数的静电纺丝纤维膜增强水凝胶。首先通过静电纺丝构建有序纤维膜，成功提高了其拉伸强度和模量。然后用PVA/PAA/GO多层有序静电纺丝膜对PVA/PAA/GO水凝胶进行逐层改性。有序纤维膜以模仿软骨中胶原纤维的方式显著增强了机械强度和摩擦性能。当膜层数为4时，纤维膜增强水凝胶的机械性能达到最大值，可与天然软骨相媲美，其拉伸强度可达13.7±1.5MPa，拉伸模量为27.5±3.2MPa，压缩强度为12.32±1.35MPa，压缩模量为20.35±2.50MPa。有序纤维膜赋予水凝胶更高的撕裂能，为39.16±4.05KJ/m，是纯凝胶（7.74±0.86KJ/m）的5倍。此外，纤维膜增强水凝胶的摩擦系数低至0.039，比未添加纤维膜的水凝胶小2倍。因此，这种水凝胶具有优异的机械性能和摩擦学性能，可广泛应用于软骨替代等组织工程领域。
