天然氨基酸生物材料的自组装与细胞相容性研究

Study on the Self-assembly and Cytocompatibility of the Natural Amino Acid Biomaterials

天然氨基酸(NAA)是一种具有良好生物相容性的材料,对其进行功能化设计是近年来的热门研究领域。本文中将基于蚕丝蛋白的特征氨基酸序列(Gly-Ala)与离子互补多肽序列(Arg-Ala-Asp-Ala)混编,设计了多肽RAG-16。采用原子力显微镜、旋转流变仪、傅立叶变换红外光谱仪、倒置荧光显微镜等技术对多肽RAG-16的自组装结构、流变学性能以及细胞相容性等性质进行了表征。结果表明:多肽RAG-16在溶液中具有自组装特性,能够形成纳米级三维网络结构,所形成的水凝胶力学性能较佳。通过分析得知,多肽二级结构中Silk I结构比例增加是其力学性能增强的主要原因。荧光染色显示,绝大多数接种于多肽水凝胶中的MC3T3-E1细胞能够存活,且能在不同的三维平面上生长增殖,表明该材料具有良好的细胞相容性。综上所述,本实验中设计的NAA材料在生物医学领域有较大的应用潜力。

Functional designing of natural amino acids （NAA） has received considerable attention in recent years due to its excellent biocompatibility. A novel self-assembling NAA, peptide RAG-16, was designed by hybridizing the characteristic silk fibroin motif （Gly-Ala） with an ionic complementary peptide sequence （Arg-Ala-Asp-Ala） in our study. The self-assembly structure, viscoelastic property, and cyto compatibility of the peptide were investigated by atomic force microscopy, rheometer, fourier transform infrared spectrum, and inverted fluorescence microscope. RAG-16 was able to form a three-dimensional compact network structure in water. High mechanical performance of the peptide hydrogel was found due to the increase of the silk I structure from inserted fihroin motif segment. Fluo- rescence staining showed that vast majority of MC3T3-E1 cells in the RAG-16 hydrogel could adhere to, survive, and distribute on different planes. To sum up, in this experiment, the functional designing of the NAA has exhibited its potential application in biomedical field.