In situ atomic force microscopy of partially demineralized human dentin collagen fibrils
In situ atomic force microscopy of partially demineralized human dentin collagen fibrils
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DOI：
10.1016/s1047-8477(02)00029-1
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发表时间：
2002-06-01
影响因子：
3
通讯作者：
Marshall, GW
中科院分区：
文献类型：
--
作者：
Habelitz, S;Balooch, M;Marshall, GW
通过原子力显微镜（AFM）原位研究牙本质胶原纤维。提出了关于水合和脱水 I 型胶原原纤维的尺寸分布和轴向重复距离的新数据。第三磨牙的抛光牙本质盘用柠檬酸部分脱矿质，留下蛋白质和胶原蛋白基质。在此阶段，AFM 尚未分辨出胶原原纤维，但在暴露于 NaOClaq 100-240 秒后，可能是由于非胶原蛋白的去除，单个胶原原纤维和与矿化基质连接的牙本质原纤维网络显露出来。使用轻敲模式下的高纵横比硅尖端对软原纤维网络进行成像。水合原纤维显示出三组不同的直径：100、91 和 83 nm，轴向重复距离的狭窄分布为 67 nm。脱水导致原纤维直径广泛分布在 75 至 105 nm 之间，并且轴向重复距离分为三组，分别为 67、62 和 57 nm。在水合和脱水原纤维上观察到亚原纤维特征（4 nm）。原纤维的厚重复段和薄重复段之间的间隙深度从 3 nm 到 7 nm 不等。相模式揭示了从原纤维的间隙到重叠区域过渡的矿物颗粒。这种方法似乎是分析钙化组织中纤维状胶原蛋白结构的有力工具，并且可能有助于了解化学治疗或疾病影响的胶原蛋白差异。 (C) 2002 年爱思唯尔科学（美国）。版权所有。
Dentin collagen fibrils were studied in situ by atomic force microscopy (AFM). New data on size distribution and the axial repeat distance of hydrated and dehydrated collagen type I fibrils are presented. Polished dentin disks from third molars were partially demineralized with citric acid, leaving proteins and the collagen matrix. At this stage collagen fibrils were not resolved by AFM, but after exposure to NaOClaq for 100-240 s, and presumably due to the removal of noncollagenous proteins, individual collagen fibrils and the fibril network of dentin connected to the mineralized substrate were revealed. High-aspect-ratio silicon tips in tapping mode were used to image the soft fibril network. Hydrated fibrils showed three distinct groups of diameters: 100, 91, and 83 nm and a narrow distribution of the axial repeat distance at 67 nm. Dehydration resulted in a broad distribution of the fibril diameters between 75 and 105 nm and a division of the axial repeat distance into three groups at 67, 62, and 57 nm. Subfibrillar features (4 nm) were observed on hydrated and dehydrated fibrils. The gap depth between the thick and thin repeating segments of the fibrils varied from 3 to 7 nm. Phase mode revealed mineral particles on the transition from the gap to the overlap zone of the fibrils. This method appears to be a powerful tool for the analysis of fibrillar collagen structures in calcified tissues and may aid in understanding the differences in collagen affected by chemical treatments or by diseases. (C) 2002 Elsevier Science (USA). All rights reserved.