Fibrin structural and diffusional analysis suggests that fibers are permeable to solute transport
Fibrin structural and diffusional analysis suggests that fibers are permeable to solute transport
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DOI：
10.1016/j.actbio.2016.09.044
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发表时间：
2017-01-01
影响因子：
9.7
通讯作者：
Van Oosterwyck, Hans
中科院分区：
文献类型：
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作者：
Leonidakis, Kimon Alexandros;Bhattacharya, Pinaki;Van Oosterwyck, Hans
纤维蛋白水凝胶是组织工程中很有前途的载体材料。它们具有生物相容性且易于制备，可以结合生长因子，并且可以从患者自己的血液中制备。虽然纤维蛋白的结构和力学已被广泛研究，但对于网络内溶质的结构和扩散率之间的关系知之甚少。这对于尺寸与生长因子相似的溶质尤其重要。本研究采用了一种新颖的方法学方法，通过结合两种互补技术，即具有纤维提取算法的共焦荧光显微镜和浊度测量，来检索纤维蛋白水凝胶的定量结构特征。进行体积流变测量以确定纤维蛋白水凝胶结构对机械性能的影响。从这些测量结果可以得出结论，纤维蛋白水凝胶结构的变化对水凝胶的流变响应有很大影响（储能模量差异高达两个数量级），但对葡聚糖溶质的扩散率影响不大（差异高达 25%）。通过利用奥格斯顿扩散模型分析扩散率测量结果，我们进一步提供了证据，表明单个纤维蛋白纤维可以对溶质运输具有半渗透性，具体取决于单个原纤维之间的平均距离。这对于减少质量传输限制、调节纤维蛋白溶解和生长因子结合非常重要，这些都与组织工程相关。意义声明纤维蛋白是一种天然生物聚合物，作为组织工程应用中的仿生载体引起了人们的广泛兴趣。我们特此使用一种基于光学显微镜和光散射方法的新型组合方法来表征纤维蛋白网络的结构，该方法也可应用于其他纤维状水凝胶，如胶原蛋白。此外，我们关于溶质转运和纤维蛋白结构特性之间关系的发现可以导致用于控制释放应用的纤维蛋白水凝胶结构的优化设计。最后，我们提供了新的证据，证明纤维蛋白纤维可能可渗透分子量与生长因子相当的溶质。这一发现可能为定制纤维蛋白载体的质量运输特性开辟新途径。 (C) 2016 Acta Materialia Inc. 由 Elsevier Ltd 出版。保留所有权利。
Fibrin hydrogels are promising carrier materials in tissue engineering. They are biocompatible and easy to prepare, they can bind growth factors and they can be prepared from a patient's own blood. While fibrin structure and mechanics have been extensively studied, not much is known about the relation between structure and diffusivity of solutes within the network. This is particularly relevant for solutes with a size similar to that of growth factors. A novel methodological approach has been used in this study to retrieve quantitative structural characteristics of fibrin hydrogels, by combining two complementary techniques, namely confocal fluorescence microscopy with a fiber extraction algorithm and turbidity measurements. Bulk rheological measurements were conducted to determine the impact of fibrin hydrogel structure on mechanical properties. From these measurements it can be concluded that variations in the fibrin hydro gel structure have a large impact on the rheological response of the hydrogels (up to two orders of magnitude difference in storage modulus) but only a moderate influence on the diffusivity of dextran solutes (up to 25% difference). By analyzing the diffusivity measurements by means of the Ogston diffusion model we further provide evidence that individual fibrin fibers can be semi-permeable to solute transport, depending on the average distance between individual protofibrils. This can be important for reducing mass transport limitations, for modulating fibrinolysis and for growth factor binding, which are all relevant for tissue engineering.Statement of SignificanceFibrin is a natural biopolymer that has drawn much interest as a biomimetic carrier in tissue engineering applications. We hereby use a novel combined approach for the structural characterization of fibrin networks based on optical microscopy and light scattering methods that can also be applied to other fibrillar hydrogels, like collagen. Furthermore, our findings on the relation between solute transport and fibrin structural properties can lead to the optimized design of fibrin hydrogel constructs for controlled release applications. Finally, we provide new evidence for the fact that fibrin fibers may be permeable for solutes with a molecular weight comparable to that of growth factors. This finding may open new avenues for tailoring mass transport properties of fibrin carriers. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.