Tawa Keiko, Izumi Shota, Sasakawa Chisato, Hosokawa Chie, Toma Mana
Opt Express. 2017 May 1;25(9):10622-10631. doi: 10.1364/OE.25.010622.
A Bull's eye-plasmonic chip composed of concentric circles was applied to enhanced fluorescence microscopy. Among one dimensional (1-D), 2-D, and Bull's eye periodic structures, the Bull's eye-plasmonic chip provided the most enhanced fluorescence intensity under the epi-fluorescence microscope, because incident light through the objective lens with all azimuthal angles can be effectively applied to the surface plasmon resonance- field (excitation field) and the plasmon-enhanced emission was also effectively collected. In the fluorescence observation of a single nanoparticle, the enhanced fluorescence images for a microsphere with ϕ 2 μm and a nanosphere with ϕ 200 nm were observed. For the nanospheres with ϕ 40 and 20 nm, the fluorescence image, which was undetectable on a glass slide, was observed in a spatial resolution of roughly diffraction limit on the Bull's eye-plasmonic chip. Furthermore, the use of an appropriate pinhole at the aperture stop in the incident optical system improved the fluorescence enhancement. The applicability of a Bull's eye-plasmonic chip to fluorescence imaging was demonstrated.
一种由同心圆组成的靶心等离子体芯片被应用于增强荧光显微镜。在一维（1-D）、二维和靶心周期性结构中，靶心等离子体芯片在落射荧光显微镜下提供了最强的荧光强度，因为通过物镜以所有方位角入射的光都可以有效地应用于表面等离子体共振场（激发场），并且等离子体增强发射也能被有效地收集。在单个纳米颗粒的荧光观察中，观察到了直径为2μm的微球和直径为200nm的纳米球的增强荧光图像。对于直径为40nm和20nm的纳米球，在玻璃载玻片上无法检测到的荧光图像，在靶心等离子体芯片上以大致衍射极限的空间分辨率被观察到。此外，在入射光学系统的孔径光阑处使用合适的针孔提高了荧光增强效果。证明了靶心等离子体芯片在荧光成像中的适用性。
