Fig. 2. The titration fluorescence spectra of HMN (10 μM) upon addition of (A) Cys (0–100 equiv.), (B) Hcy (0–100 equiv.), (C) GSH (0–100 equiv.), (D) H2S(LC) (0–50 equiv.), and (E) H2S(LC) (50–500 equiv.) in PBS (25 mM, pH 7.4, containing 20% acetonitrile). Excitation at 410 nm for the first column, 470 nm for the second column, and 550 nm for the third column. H2S(LC) and H2S(HC) denote H2S at low and high concentration, respectively.
