Terzi Alberta, Gallo Nunzia, Bettini Simona, Sibillano Teresa, Altamura Davide, Campa Lorena, Natali Maria Lucia, Salvatore Luca, Madaghiele Marta, De Caro Liberato, Valli Ludovico, Sannino Alessandro, Giannini Cinzia
Institute of Crystallography (IC), National Research Council, Bari, Italy.
Department of Engineering for Innovation, University of Salento, Lecce, Italy.
Front Bioeng Biotechnol. 2019 Aug 26;7:203. doi: 10.3389/fbioe.2019.00203. eCollection 2019.
The aim of this work is to evaluate the effects of different extraction and material processing protocols on the collagen structure and hierarchical organization of equine tendons. Wide and Small Angle X-ray Scattering investigations on raw powders and thin films revealed that not only the extraction and purification treatments, but also the processing conditions may affect the extent of the protein crystalline domain and induce a nanoscale "shield effect." This is due to the supramolecular fiber organization, which protects the atomic scale structure from the modifications that occur during fabrication protocols. Moreover, X-ray analyses and Fourier Transform Infrared spectroscopy performed on the biomaterial sheds light on the relationship between processing conditions, triple helical content and the organization in atomic and nanoscale domains. It was found that the mechanical homogenization of the slurry in acidic solution is a treatment that ensures a high content of super-organization of collagen into triple helices and a lower crystalline domain in the material. Finally, mechanical tensile tests were carried out, proving that the acidic solution is the condition which most enhances both mechanical stiffness and supramolecular fiber organization of the films.
这项工作的目的是评估不同的提取和材料加工方案对马肌腱胶原蛋白结构和层次组织的影响。对原始粉末和薄膜进行的广角和小角X射线散射研究表明，不仅提取和纯化处理，而且加工条件也可能影响蛋白质结晶域的程度，并诱导纳米级的“屏蔽效应”。这是由于超分子纤维组织，它保护原子尺度结构免受制造过程中发生的改性影响。此外，对生物材料进行的X射线分析和傅里叶变换红外光谱揭示了加工条件、三螺旋含量以及原子和纳米尺度域中的组织之间的关系。研究发现，在酸性溶液中对浆料进行机械均质化处理可确保胶原蛋白高度超组织化为三螺旋，且材料中的结晶域较低。最后，进行了机械拉伸试验，证明酸性溶液是最能提高薄膜机械刚度和超分子纤维组织的条件。
