Fig. 6. (a) Fluorescence emission spectra of the sensing system in the presence of different amounts of S2−, (b) ratio of the fluorescence emission intensity at 610 nm to 490 nm (excitation, 400 nm) as a function of log S2− concentration, (c) fluorescence emission spectra of the sensing system in the presence of 10 μM of amino acid and S2− and (d) selectivity of the sensor for S2− over common amino acids (GSH was also used).
