Plasmonic core-shell luminescent nanoparticles: A self-supporting sensing platform

等离激元核壳发光纳米粒子：自支撑传感平台

• 批准号: RGPIN-2015-06468
• 负责人: Boudreau, Denis
• 金额: $ 2.55万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=645930
• 关键词: Plasmonic; core; shell; luminescent; nanoparticles

The confinement of electromagnetic fields within metallic nanoparticles is at the origin of the optical phenomenon known as localized surface plasmon resonance (LSPR). This confinement is associated with large enhancements in local field intensity, which lead in turn to significant increases in the quantum yield and radiative rates of fluorescent species placed close to the metal surface. Furthermore, one can take advantage of the LSPR frequency's dependence on the composition, geometry, size and dielectric environment of metallic nanoparticles to design optimal nanostructures able to enhance the emission intensity of fluorophores across the spectrum from UV to the near infrared (NIR). ***A significant reduction of self-quenching (i.e. signal losses occurring between neighboring fluorophores) and an  enhancement of detection sensitivity and photostability can be obtained with core-shell nanoparticles composed of a nanometer-size silver core coated by multiple layers of silica. By careful control of the spacing between the core and fluorophores arranged in concentric layers, these nanostructures can be used to enhance Förster resonant energy transfer (FRET) efficiency and range between donor-acceptor pairs localized on these multilayer composite NPs. We recently demonstrated the use of these nanoprobes as plasmonic enhancers for weakly fluorescent analytes, for the quantitative detection of specific genes at the trace level and for photostable imaging of physiological ions near cellular membranes.****These multilayer core-shell nanoparticles present many of the features required of an ideal self-supported sensing platform: they offer high optical detection sensitivity, excellent chemical and photophysical stability, high dispersability in water, and facile surface functionalization. Furthermore, their mobility is an asset for probing the contents of extended sample volumes in biosensing applications or for functional cell imaging work. In this research program, we will design novel multilayer core-shell fluorescent nanoarchitectures that maximize plasmonic enhancement of luminescence and FRET, investigate their photophysical characteristics, and develop them into molecular sensing nanostructures for the sensitive detection of trace amounts of genes, biomarkers, toxins, pathogens, tumor cells, etc. and other applications in the fields of analytical chemistry, materials science, plasmonics, photonics and biotechnology.**

金属纳米粒子内电磁场的限制是被称为局域表面等离子体共振（LSPR）的光学现象的根源，这种限制与局部场强度的大幅增强相关，从而导致量子产率和量子产率的显着增加。此外，人们可以利用局域表面等离子体共振频率对金属纳米粒子的成分、几何形状、尺寸和介电环境的依赖性来设计最佳的辐射率。纳米结构能够增强从紫外到近红外 (NIR) 光谱范围内荧光团的发射强度​*** 显着减少自猝灭（即相邻荧光团之间发生的信号损失）并提高检测灵敏度和光稳定性。通过仔细控制核与银之间的间距，可以得到由多层二氧化硅包覆的纳米级银核组成的核-壳纳米粒子。荧光团排列在同心层中，这些纳米结构可用于增强福斯特共振能量转移 (FRET) 效率和这些多层复合纳米粒子上供体-受体对之间的范围，我们最近演示了这些纳米探针作为弱荧光分析物的等离子体增强剂的用途。 ，用于痕量水平上特定基因的定量检测以及细胞膜附近生理离子的光稳定性成像。****这些多层核-壳纳米粒子呈现理想的自支撑传感平台所需的许多功能：它们具有高光学检测灵敏度、优异的化学和光物理稳定性、在水中的高分散性以及易于表面功能化。此外，它们的流动性是探测扩展内容的资产在本研究项目中，我们将设计新型多层核壳荧光纳米结构，最大限度地提高发光和 FRET 的等离激元增强，研究其光物理特性，并将其开发为分子。传感纳米结构，用于灵敏检测痕量基因、生物标记物、毒素、病原体、肿瘤细胞等，以及分析化学、材料科学、等离子学、光子学和生物技术领域的其他应用。**