Innovative Plasmonic Platforms for Advanced Molecular Sensing

目前的研究提案试图将重点放在一个被称为等离子的纳米技术领域。等离子激元领域依赖于当某些纳米尺度的金属，如硬币金属，与入射电场，如光的电场分量相互作用时观察到的独特的光学和电子效应。这种相互作用产生所谓的表面等离子激元，这种等离子体既可以被限制在纳米金属的表面上，也可以沿着纳米金属的表面传播，这取决于它的大小和尺寸。这些表面等离子体具有显著的属性，最显著的是在纳米尺度上获取和操纵光的能力，导致高灵敏度的化学传感和近场光学显微镜和等离子体电路的前所未有的未来发展。这种先进材料具有广泛的可能和示范应用，从增强的太阳能转换到超级透镜和光学隐形。这里概述的研究计划围绕着与使用创新等离子体平台的先进分子传感相关的三个主要主题：(I)增强的灵敏度(Ii)改进的选择性和(Iii)未来的可持续性；这些领域概述如下。*(I)增强的灵敏度。虽然理论研究已经证明，等离子体纳米粒子的出色光操作应该允许进行单分子水平的检测，但缺乏此类检测极限的常规证据。解决这一问题的方法不仅在于能够制备尺寸和形状上具有极佳单分散性的纳米颗粒，而且在于能够以最低的成本在大的表面积上以所需的构型制造这种结构的组装。我们解决这些问题的方法将是探索几种策略，包括逐层沉积、生物支架和等离子体超分子阵列，以创建新的等离子体平台。*(二)增强了选择性。一个持续困扰等离子体传感进展的问题是非靶标分析物与传感器表面的非特异性相互作用。我们的方法将是扩大我们在目标分析物检测的aptasensors领域的探索性工作。此外，我们还将探索电化学表面增强拉曼光谱(SERS)在多大程度上可以用于提高选择性。*III)未来的可持续性。目前的等离子体金属，如金和银，存在成本高的缺点，特别是对金，以及有限的长期可获得性，特别是对银。作为该计划的一部分，我们计划探索将铜和铝纳米颗粒用于等离子体应用。与这种纳米结构的合成和稳定性有关的问题将通过离子液体稳定的纳米颗粒合成和电化学沉积等方法来规避。***********

The present research proposal seeks to focus on an area of nanotechnology termed plasmonics. The field of plasmonics relies on the unique optical and electronic effects observed when certain nanoscale metals, such as the coinage metals, interact with incident electric fields, such as the electric field component of light. Such interaction generates what are termed surface plasmons, which can be either confined to the surface or can propagate along the surface of a nanometal, depending on its size and dimensions. These surface plasmons have remarkable attributes, most notably the ability to harvest and manipulate light at the nanoscale, leading to highly sensitive chemical sensing and unprecedented future developments in near-field optical microscopy and plasmonic circuitry. Such advanced materials have an enormous range of possible and demonstrated applications, ranging from enhanced solar-energy conversion to superlenses and optical cloaking. The research program outlined herein revolves around three main themes related to advanced molecular sensing using innovative plasmonic platforms: (i) enhanced sensitivity (ii) improved selectivity and (iii) future sustainability; these areas are summarized below.***(i) Enhanced sensitivity. While theoretical studies have demonstrated that the excellent light-manipulation of plasmonic nanoparticles should allow for single molecule level detection; routine evidence of such detection limits is lacking. A solution to this problem lies in the ability to not only fabricate nanoparticles with excellent monodispersity in terms of size and shape, but also in the ability to fabricate assemblies of such structures in a desired configuration over large surface areas with minimal cost. Our approach to overcome these issues will be to explore several strategies including layer-by-layer deposition, bioscaffolding and plasmonic metamolecular arrays for creating novel plasmonic platforms. ******(ii) Enhanced selectivity. One problem that continually plagues advances in plasmonic sensing is the non-specific interaction of non-target analytes with the sensor surface. Our approach will be to expand on our exploratory work in the field of aptasensors for target analyte detection. In addition, we will explore the extent to which electrochemical surface enhanced Raman spectroscopy (SERS) can be used to enhance selectivity. ******iii) Future sustainability. Current plasmonic metals, such as Au and Ag, suffer from the disadvantage of high cost, especially for gold, as well as limited long term availability, especially for silver. As part of this program, we plan to explore the use of copper and aluminum nanoparticles for plasmonic applications. Issues associated with the synthesis and stability of such nanostructures will be circumvented using methods such as ionic liquid stabilized nanoparticle synthesis and electrochemical deposition. ***********