Figure 2: Fluorescence titration spectra of CPT.

(A) Fluorescence titration spectra of CPT (2.5 μM) with incremental concentration of HSO₃⁻ (0–5 equiv.). Data are mean SE (bars) (n = 3); (B) Fluorescence spectra of probe CPT in the presence of various analytes (100 equiv.) in EtOH-H₂O solution (6:4 v/v, 10 mM PBS, pH 8.0).