Simple and rapid determination of thiol compounds by HPLC and fluorescence detection with 1,3,5,7-tetramethyl-8-phenyl-(2-maleimide) difluoroboradiaza-s-indacene

A rapid and simple background-free high-performance liquid chromatographic (HPLC) approach has been developed for simultaneously determining free thiol compounds including coenzyme A (CoA), cysteine (Cys), glutathione (GSH) and N-acetyl-cysteine (NAC) in biological samples by using 1,3,5,7-tetramethyl-8-phenyl-(2-maleimide) difluoroboradiaza-s-indacene (TMPAB-o-M) as fluorogenic reagent. After derivatization under physiological conditions within 6 min, baseline separation was finished in just 6 min using isocratic elution with reversed-phase HPLC and fluorescence detection. Excellent linearity was observed for all analytes over their concentration ranges of 1–500 nM and detection limits ranging 0.13 nM for CoA to 0.25 nM for Cys (S/N = 3) were achieved. The utility of the proposed method has been validated by measuring thiol compounds mentioned above in tissue, fluid and cell samples. The results indicated that this approach was well suited for high-throughput quantitative determination of thiols and study of the physiological role of them.