SGER: Single Nanoparticle Surface Plasmon Resonance Imaging

特拉华大学的卡尔·S·布克什教授在化学系分析和表面化学项目的支持下，开发了一种扫描、单粒子表面等离子体共振光谱技术，应用于纳米尺度非均质材料的无标记成像。将单个金或银纳米颗粒放置在近场扫描光学显微镜的光纤探头的尖端。通过调整纳米粒子探头的大小和形貌，等离子体激元的场将被整形和聚焦。被探头表面折射率的变化会影响固定在探头尖端的粒子的表面等离子体共振频率。这将使纳米级非均质材料的局部介电常数的高分辨率映射成为可能，而不需要染料或报告分子。目前还没有如此高分辨率的非侵入性成像方法。所提出的成像技术将有助于表征自组装膜、脂质双层和软聚合物等材料的表面，并将导致纳米科学和技术、表面化学和生物技术的创新。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Professor Karl S. Booksh of the University of Delaware is supported by the Analytical and Surface Chemistry Program in the Division of Chemistry to develop a scanning, single particle surface plasmon resonance spectroscopy technique to be applied for label-free imaging of nanoscale heterogeneous materials. A single gold or silver nanoparticle will be placed on the tip of an optical fiber probe of a near-field scanning optical microscope. The plasmon field will be shaped and focused by adjusting the size and morphology of the nanoparticle probe. Refractive index changes on the probed surface will affect the surface plasmon resonance frequency of the particle immobilized at the tip of the probe. This will enable the high-resolution mapping of local dielectric constants of nanoscale heterogeneous materials without the need for dyes or reporter molecules. Such a high resolution, non-invasive imaging method is currently not available. The proposed imaging technique will be useful for characterization of surfaces of materials such as SAMs, lipid bilayers, and soft polymers, and will lead to innovations in nanoscience and technology, surface chemistry, and biotechnology.