Nanoscale Plasmonic V-Groove Waveguides for the Interrogation of Single Fluorescent Bacterial Cells

作者：Lotan Oren; Bar David Jonathan; Smith Cameron L C; Yagur Kroll Sharon; Belkin Shimshon; Kristensen Anders; Levy Uriel^*

来源：Nano Letters, 2017, 17(9): 5481-5488.

DOI：10.1021/acs.nanolett.7b02132

• Aluminum plasmonics
• bio-plasmonic chips
• fluorescent bacterial cells
• bacterial biosensors
• nanoscale plasmonic V-groove waveguides
• single-bacterium excitation

We experimentally demonstrate the interrogation of an individual Escherichia coli cell using a nanoscale plasmonic V-groove waveguide. Several different configurations were studied. The first involved the excitation of the cell in a liquid environment because it flows on top of the waveguide nanocoupler, while the obtained fluorescence is coupled into the waveguide and collected at the other nanocoupler. The other two configurations involved the positioning of the bacterium within the nanoscale waveguide and its excitation in a dry environment either directly from the top or through waveguide modes. This is achieved by taking advantage of the waveguide properties not only for light guiding but also as a mechanical tool for trapping the bacteria within the V-grooves. The obtained results are supported by a set of numerical simulations, shedding more light on the mechanism of excitation. This demonstration paves the way for the construction of an efficient bioplasmonic chip for diverse cell based sensing applications.

• 出版日期2017-9