[14a-3A-1~8] English session: Asian Joint Symposium on Nanobiotechnology

▲ [14a-3A-6] Sensitive single-particle fluorescence imaging with a plasmonic chip

〇Keiko Tawa^1,2, Chisato Sasakawa^1,2, Chie Hosokawa^2,1 (1.Kwansei Gakuin Univ., 2.AIST)

Keywords:Plasmon,Fluorescence imaging,Single particle

A plasmonic chip which is a metal-coated substrate with a wavelength-scale grating can provide the enhanced fluorescence. Therefore, it has been applied to in situ sensitive fluorescence imaging of cells. Neuronal cells were successfully cultured for more than 3 weeks on the plasmonic chip and bright fluorescence images of dendrites were observed with a conventional fluorescence microscope. In this study, the spatial resolution and the fluorescence enhancement in a single-nanoparticle fluorescence imaging were examined. Fluorescently labeled-nanoparticles with 3 kinds of diameters of 40 nm, 200 nm, and 1 micro m were used and they were observed under the epi-fluorescence microscope. The fluorescence intensities in the single-particle fluorescence images were compared between on the glass slide and on the plasmonic chip. In the observation of 40 nm-particles with 100 x objective, the diameter of a particle was evaluated as 450 nm, i.e., a value of diffraction limit. The enhancement factors of fluorescence intensities were several times to 20 times.