以短肽组装体为模板仿生矿化二氧化硅纳米管

Biomimetic Synthesis of Silica Nanotubes by Using Short Peptide Self-assemblies as Templates

目的二氧化硅纳米管由于具有生物相容性好、光学性质优异等特殊性能在不同领域展现出良好的应用前景,其尺寸和形貌可显著影响材料性质。为制备尺寸较大的纳米管并拓展其在不同领域的应用,本研究选择尺寸较大的多肽组装体为模板,进行二氧化硅的仿生矿化。方法以Bola型多肽Ac-KI3VK-CONH2自组装形成的尺寸较大(直径约40 nm)的纳米管为模板,通过仿生矿化的方法制备二氧化硅纳米材料。首先考察了多肽纳米管的稳定性,发现在稀释、加入有机溶剂和改变溶液pH值时,纳米管的形貌均被破坏,展示出较差的稳定性。在此基础上,以该多肽纳米管为模板,选择反应速率较快的正硅酸甲酯(TMOS)为前驱体仿生矿化二氧化硅纳米材料,探索了不同矿化条件对二氧化硅纳米管尺寸和形貌的影响。结果以反应速率较快的TMOS为硅源、体积百分比浓度为1.11%~3.33%、溶液为中性或者弱碱性时能够矿化形成形貌和尺寸较大且分布均匀的二氧化硅纳米管。结论通过选择合适的多肽组装体模板和反应速率快的TMOS为硅源,成功制备出了尺寸较大的二氧化硅纳米管,这为拓展其在不同领域的应用奠定了基础,具有重要意义。

Objective As for the unique properties of good biocompatibility and excellent optical performance,silica nanotubes have shown potential applications in different fields.The properties of the silica nanotubes were well correlated with their size and morphologies.In order to prepare silica nanotubes with much larger size and expand their applications in different fields,this study selected wide peptide nanotubes as templates for biomimetic synthesis of silica materials.Methods In order to obtain silica nanotubes with relative large size,here we prepared silica nanotubes by using wide nanotubes(with diameters of approximately 40 nm)self-assembled by the bola peptide Ac-KIVK-CONHas templates through a biomimetic mineralization route.The stability of the peptide nanotubes was firstly investigated and the results demonstrated that these nanotubes can be easily destroyed by dilution,addition of organic solvents,or changing the solution pH value,showing poor stability.Then,we chose methyl n-silicate(TMOS)with fast reaction rate as the precursor to prepare silica nanomaterials and systemically explored the influence of different factors on the size and morphology of the silica nanotubes.Results The results demonstrated that the ideal condition for preparing silica nanotubes with uniform shape and size was using TMOS as precursor and keeping its concentration at 1.11%-3.33%(v/v)under neutral or weak alkaline conditions.Conclusion This work successfully prepared silica nanotubes with relative large diameter by using self-assemblies formed by a bola peptide as templates and silicon source with fast reaction rate,which is of great significance and may expand the applications of wide silica nanotubes in different fields.