Mechanical characterization of collagen-glycosaminoglycan scaffolds
Mechanical characterization of collagen-glycosaminoglycan scaffolds
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DOI：
10.1016/j.actbio.2006.12.009
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发表时间：
2007-07-01
影响因子：
9.7
通讯作者：
Gibson, Lorna J.
中科院分区：
文献类型：
--
作者：
Harley, Brendan A.;Leung, Janet H.;Gibson, Lorna J.
组织工程支架被广泛用作细胞外基质(ECM)的三维类似物。然而，人们对支架的微观结构和力学性能的研究较少，而对支架的加工和生物活性的研究相对较少。胶原蛋白-糖胺聚糖(CG)支架长期以来一直被用作皮肤再生的ECM类似物，目前正被考虑用于神经和结膜的再生。近年来，一系列具有均匀微孔结构的CG支架被开发出来，其孔径大小不一。实验表征和理论建模技术已经被用来描述这些变体的孔微结构、比表面积、细胞附着和渗透性。报告了这些CG脚手架的拉伸和压缩测试以及定义脚手架网络的单个压杆的弯曲测试结果。CG支架表现出低密度、开孔泡沫的应力-应变行为特征，具有明显的线弹性、崩塌平台和致密化区域。具有等轴孔的支架在力学上是各向同性的。确定了水化程度、孔径、交联度和相对密度对力学性能的独立影响。实现了支架刚度和孔径的独立控制。支架力学特性的实验结果与均匀支架的低密度开孔泡沫模型预测结果符合得很好。这些具有特征性的支架变体为细胞和支架之间的力学相互作用的体外研究以及体内组织工程研究提供了一个具有明确细胞外环境(微观结构和力学)的标准化框架。(C)2007年Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Tissue engineering scaffolds are used extensively as three-dimensional analogs of the extracellular matrix (ECM). However, less attention has been paid to characterizing the scaffold microstructure and mechanical properties than to the processing and bioactivity of scaffolds. Collagen-glycosaminoglycan (CG) scaffolds have long been utilized as ECM analogs for the regeneration of skin and are currently being considered for the regeneration of nerve and conjunctiva. Recently a series of CG scaffolds with a uniform pore microstructure has been developed with a range of sizes of equiaxed pores. Experimental characterization and theoretical modeling techniques have previously been used to describe the pore microstructure, specific surface area, cell attachment and permeability of these variants. The results of tensile and compressive tests on these CG scaffolds and of bending tests on the individual struts that define the scaffold network are reported here. The CG scaffold variants exhibited stress-strain behavior characteristic of low-density, open-cell foams with distinct linear elastic, collapse plateau and densification regimes. Scaffolds with equiaxed pores were found to be mechanically isotropic. The independent effects of hydration level, pore size, crosslink density and relative density on the mechanical properties was determined. Independent control over scaffold stiffness and pore size was obtained. Good agreement was observed between experimental results of scaffold mechanical characterization and low-density, open-cell foam model predictions for uniform scaffolds. The characterized scaffold variants provide a standardized framework with defined extracellular environments (microstructure, mechanics) for in vitro studies of the mechanical interactions between cells and scaffolds as well as in vivo tissue engineering studies. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.