Peptide-Directed Assembly of Single-Helical Gold Nanoparticle Superstructures Exhibiting Intense Chiroptical Activity.
Peptide-Directed Assembly of Single-Helical Gold Nanoparticle Superstructures Exhibiting Intense Chiroptical Activity.
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DOI：
10.1021/jacs.6b07322
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发表时间：
2016-10-19
影响因子：
15
通讯作者：
Rosi NL
中科院分区：
文献类型：
--
作者：
Merg AD;Boatz JC;Mandal A;Zhao G;Mokashi-Punekar S;Liu C;Wang X;Zhang P;van der Wel PCA;Rosi NL
手性纳米粒子组件是一类有趣的材料，其手性特性使其在各种应用中具有吸引力。在这里，C18-(PEPAuM-ox)2 （PEPAuM-ox = AYSSGAPPMoxPPF）被证明可以指导单螺旋金纳米粒子超结构的组装，这些超结构在等离子体频率下表现出异常强烈的热效应，绝对g因子值高达0.04。透射电子显微镜（TEM）和低温电子断层扫描（cryo-ET）结果表明，单螺旋的周期间距约为100 nm，由长方形的金纳米颗粒组成。采用透射电镜（TEM）、原子力显微镜（AFM）、傅里叶变换红外光谱（FTIR）、圆二色光谱（CD）、x射线衍射（XRD）和固态核磁共振光谱（ssNMR）研究了C18-(PEPAuM-ox)2的形貌和组装结构。透射电镜和原子力显微镜显示，C18-(PEPAuM-ox)2组装成线性淀粉样一维螺旋带，其结构参数与单螺旋金纳米颗粒的超结构相关。FTIR、CD、XRD、ssNMR等表征结果表明，产物中存在交叉β和聚脯氨酸II （PPII）二级结构。提出了一种分子组装模型，该模型考虑了所有实验观察结果，并支持单螺旋纳米颗粒组装结构。该模型为未来设计具有可编程结构和性能的纳米粒子组件提供了基础。
Chiral nanoparticle assemblies are an interesting class of materials whose chiroptical properties make them attractive for a variety of applications. Here, C18-(PEPAuM-ox)2 (PEPAuM-ox = AYSSGAPPMoxPPF) is shown to direct the assembly of single-helical gold nanoparticle superstructures that exhibit exceptionally strong chiroptical activity at the plasmon frequency with absolute g-factor values up to 0.04. Transmission electron microscopy (TEM) and cryogenic electron tomography (cryo-ET) results indicate that the single helices have a periodic pitch of approximately 100 nm and consist of oblong gold nanoparticles. The morphology and assembled structure of C18-(PEPAuM-ox)2 are studied using TEM, atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, circular dichroism (CD) spectroscopy, X-ray diffraction (XRD), and solid-state nuclear magnetic resonance spectroscopy (ssNMR). TEM and AFM reveal that C18-(PEPAuM-ox)2 assembles into linear amyloid-like 1-D helical ribbons having structural parameters that correlate to those of the single-helical gold nanoparticle superstructures. FTIR, CD, XRD, and ssNMR indicate the presence of cross-β and polyproline II (PPII) secondary structure. A molecular assembly model is presented that takes into account all experimental observations and that supports the single-helical nanoparticle assembly architecture. This model provides the basis for the design of future nanoparticle assemblies having programmable structures and properties.