Mechanical properties of mineralized collagen fibrils as influenced by demineralization
Mechanical properties of mineralized collagen fibrils as influenced by demineralization
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DOI：
10.1016/j.jsb.2008.02.010
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发表时间：
2008-06-01
影响因子：
3
通讯作者：
Marshall, G. W.
中科院分区：
文献类型：
--
作者：
Balooch, M.;Habelitz, S.;Marshall, G. W.
牙本质和骨的机械性能来自于I型胶原纤维的复杂排列，在纤维外和纤维内室中用纳米晶磷灰石矿物增强。虽然已经确定了大部分矿化组织的机械性能，但有关单个原纤维力学的信息是有限的。在这里，原子力显微镜用于单个胶原纤维，以研究酸蚀刻过程中的结构和机械变化。在矿化原纤维上没有观察到间隙区的特征性67 nm周期性，但随着连续脱矿作用变得明显并越来越明显。AFM纳米压痕显示，在酸蚀刻过程中的个别胶原纤维的模量从1.5 GPa下降到50 MPa，并揭示了模量曲线遵循轴向周期性。纳米力学数据，拉曼光谱和SAXS支持的假设，即纤维内的矿物质蚀刻在一个实质上比纤维外的mineral.These研究结果是相关的理解的生物力学和钙化组织的胶原基质的设计原则。(c)2008年爱思唯尔公司All rights reserved.
Dentin and bone derive their mechanical properties from a complex arrangement of collagen type-I fibrils reinforced with nanocrystalline apatite mineral in extra- and intrafibrillar compartments. While mechanical properties have been determined for the bulk of the mineralized tissue, information on the mechanics of the individual fibril is limited. Here, atomic force microscopy was used on individual collagen fibrils to Study structural and mechanical changes during acid etching. The characteristic 67 nm periodicity of gap zones was not observed on the mineralized fibril, but became apparent and increasingly pronounced with continuous demineralization. AFM-nanoindentation showed a decrease in modulus from 1.5 GPa to 50 MPa during acid etching of individual collagen fibrils and revealed that the modulus profile followed the axial periodicity. The nanomechanical data, Raman spectroscopy and SAXS support the hypothesis that intrafibrillar mineral etches at a substantially slower rate than the extrafibrillar mineral. These findings are relevant for understanding the biomechanics and design principles of calcified tissues derived from collagen matrices. (c) 2008 Elsevier Inc. All rights reserved.