New article in Optical Materials Express
We propose a method of measuring low concentrations of fluorescent molecules located in a small volume of a liquid solvent (about 5 μl) based on the Ebbesen effect of the extraordinary transmission (EOT) of light through a state-of-the-art plasmonic crystal formed by a nanohole array perforated in the ultra-high-quality Ag film. In the method, the EOT effect is realized at the fluorescence wavelength of the detected molecules with a low transmission of light at the absorption wavelength. This approach enables the realization of high level sensor sensitivity approaching a sensitivity level of single molecules counting sensors, owing to the suppression of the sensor substrate’s inevitable parasitic luminescence. The proposed method was successfully demonstrated by detection an ultra-low concentration of Cy-5 fluorescent markers in a dimethyl sulfoxide solution corresponding to less than 1000 molecules in the sensor detection volume.
Aleksandr S. Baburin, Anton S. Gritchenko, Nikolay A. Orlikovsky, Alina A. Dobronosova, Ilya A. Rodionov, Victor I. Balykin and Pavel N. Melentiev
Optical Materials Express 9, 3, 1173-1179, 2019 (ImF 2,566)