2.6. Measurement of the Thiol Group with ThioGlo 1

Thiol groups were detected with the help of the fluorescent probe ThioGlo 1 [36, 37]. The fluorescence spectra of the ThioGlo 1 adduct with glutathione were recorded on a RF-5301 PC spectrofluorimeter (Shimadzu, Japan). The excitation and emission of the adduct were 379 and 506 nm, respectively. The stock solution of ThioGlo 1 in anhydrous DMSO (2 mM) was stored in the dark at -20°С. Prior to assay, 5 μl of a ThioGlo 1 solution in DMSO was added to a 5 μl of a mixture containing GSH or DNIC with glutathione and incubated for 3 min at ambient temperature. Fluorescence spectra were measured after the addition of 490 μl of 10 mM Na,K-phosphate buffer (pH 7.4) to the test solution.