Screening sensitive nanosensors via the investigation of shape-dependent localized surface plasmon resonance of single Ag nanoparticles
Screening sensitive nanosensors via the investigation of shape-dependent localized surface plasmon resonance of single Ag nanoparticles
复制标题
通过研究单个银纳米粒子的形状依赖性局域表面等离子体共振来筛选敏感的纳米传感器
DOI：
10.1039/c3nr01952g
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发表时间：
2013-01-01
期刊：
影响因子：
6.7
通讯作者：
Huang, Cheng Zhi
中科院分区：
文献类型：
--
作者：
Liu, Yue;Huang, Cheng Zhi
了解不同形状等离子体纳米颗粒的局域表面等离子体共振（LSPR）有利于筛选和设计高灵敏度的单纳米颗粒传感器。在此，在本工作中，我们系统地研究了形状依赖的散射光的颜色和折射率（RI）的灵敏度的银纳米粒子（AgNPs）在单个纳米粒子的水平，使用传统的暗场光散射显微镜和光谱。合成了不同形状和散射色光的AgNPs，并通过暗场显微镜（DFM）和扫描电子显微镜（SEM）对相同纳米粒子的共定位来确定形状对散射光颜色的影响。结果表明，散射蓝色，青色，黄色和红色光的银纳米粒子分别是球形，立方体，三角双锥，和棒，这使我们能够直接识别银纳米粒子的形状通过暗场显微镜，而不是电子显微镜。进一步研究了单个AgNPs对周围溶剂的散射光谱响应，发现不同形状的AgNPs的RI灵敏度大小顺序为棒状>立方体>三角双锥>球状。在通常研究的AgNP中，Ag纳米棒具有最高的RI灵敏度，其随着纵横比的增加而增加。然后，各种形状的AgNPs被用作单个纳米颗粒传感器，用于探测小分子的吸附。
Understanding the localized surface plasmon resonance (LSPR) of differently shaped plasmonic nanoparticles benefits screening and designing highly sensitive single nanoparticle sensors. Herein, in the present work, we systematically investigated the shape-dependent scattering light colours and refractive index (RI) sensitivity of Ag nanoparticles (AgNPs) at the single nanoparticle level using conventional dark-field light scattering microscopy and spectroscopy. AgNPs in various shapes and scattering colourful light were synthesized, and the shape effect on the scattering light colour was determined by the colocalization of the same nanoparticles with dark-field microscopy (DFM) and scanning electron microscopy (SEM). The results showed that the AgNPs that scattered blue, cyan, yellow, and red light are spheres, cubes, triangular bipyramids, and rods, respectively, which enable us to directly recognize the shape of AgNPs through dark-field microscopy instead of electron microscopy. Further studies on investigation of the scattering spectral responses of single AgNPs to their surrounding solvents show that the RI sensitivity of AgNPs of different shapes followed the order of rods > cubes > triangular bipyramids > spheres. Among the commonly studied AgNPs, Ag nanorods have the highest RI sensitivity, which increases as the aspect ratio increases. Then, AgNPs of various shapes were used as single nanoparticle sensors for probing the adsorption of small molecules.