Fig. 5. Changes in the fluorescence intensity of G6/nucleotide (green: ADP; red: ATP) upon addition of increasing concentrations of (a) NaCl and (b) CaCl2 in DMSO–water (1 : 9 v/v); conditions: [G6] = 6.0 μM, [nucleotide] = 20 μM, [HEPES] = 10 mM (pH 7.4), 25 °C; λ ex = 388 nm; λ em = 514 nm. (c) Fluorescence titration result of G6 upon addition of increasing concentrations of AMP (blue), ADP (green) and ATP (red) with a fixed concentration of CaCl2 (1.0 mM); conditions: [G6] = 6.0 μM; [HEPES] = 10 mM (pH 7.4); 25 °C; λ ex = 388 nm; λ em = 514 nm.
