Department of Physics, University of Central Florida, Orlando, Florida 32816-2385, USA.
Nano Lett. 2012 May 9;12(5):2342-6. doi: 10.1021/nl300286k. Epub 2012 Apr 11.
Noncovalent functionalization of graphene using peptides is a promising method for producing novel sensors with high sensitivity and selectivity. Here we perform atomic force microscopy, Raman spectroscopy, infrared spectroscopy, and molecular dynamics simulations to investigate peptide-binding behavior to graphene and graphite. We studied a dodecamer peptide identified with phage display to possess affinity for graphite. Optical spectroscopy reveals that the peptide forms secondary structures both in powder form and in an aqueous medium. The dominant structure in the powder form is α-helix, which undergoes a transition to a distorted helical structure in aqueous solution. The peptide forms a complex reticular structure upon adsorption on graphene and graphite, having a helical conformation different from α-helix due to its interaction with the surface. Our observation is consistent with our molecular dynamics calculations, and our study paves the way for rational functionalization of graphene using biomolecules with defined structures and, therefore, functionalities.
使用肽对石墨烯进行非共价功能化是一种很有前途的方法，可以生产出具有高灵敏度和选择性的新型传感器。在这里，我们通过原子力显微镜、拉曼光谱、红外光谱和分子动力学模拟来研究肽与石墨烯和石墨的结合行为。我们研究了一种十二聚肽，它通过噬菌体展示被鉴定为对石墨具有亲和力。光学光谱表明，该肽在粉末形式和水介质中都形成了二级结构。在粉末形式中占主导地位的结构是α-螺旋，它在水溶液中会发生扭曲螺旋结构的转变。该肽在吸附到石墨烯和石墨上时形成一个复杂的网状结构，由于与表面的相互作用，其构象呈螺旋状，不同于α-螺旋。我们的观察结果与我们的分子动力学计算一致，我们的研究为使用具有定义结构和功能的生物分子对石墨烯进行合理的功能化铺平了道路。
