Improving zero-mode waveguide structure for enhancing signal-to-noise ratio of real-time single-molecule fluorescence imaging: a computational study.
We investigated the signal-to-noise ratio (S/N) of real-time single-molecule fluorescence imaging (SMFI) using zero-mode waveguides (ZMWs). The excitation light and the fluorescence propagating from a molecule in the ZMW were analyzed by computational optics simulation. The dependence of the S/N on the ZMW structure was investigated with the diameter and etching depth as the simulation parameters. We found that the SMFI using a conventional ZMW was near the critical level for detecting binding and dissociation events. We show that etching the glass surface of the ZMW by 60 nm enhances the S/N six times the conventional nonetched ZMWs. The enhanced S/N improves the temporal resolution of the SMFI at physiological concentrations.
Faculty of Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo 169-8555, Japan. tanii@waseda.jp
Takashi
T
Tanii
Rena
R
Akahori
Shun
S
Higano
Kotaro
K
Okubo
Hideaki
H
Yamamoto
Taro
T
Ueno
Takashi
T
Funatsu
D003198:Computer Simulation; D005453:Fluorescence; D008962:Models, Theoretical; D057054:Molecular Imaging / Q000379:methods*; D059629:Signal-To-Noise Ratio