Sensitive ferrocene reagents for derivatization of thiol compounds in high-performance liquid chromatography with...

Three N-substituted maleimides possessing ferrocene as an electrophore were prepared and evaluated for pre-column derivatization of thiol compounds in high-performance liquid chromatography with dual-electrode coulometric detection. The utility of these reagents was investigated by employing N-acetyl-L-cysteine as a model compound. Among the three, N-(ferrocenyl) maleimide was the most favourable reagent with respect to reactivity, stability and electrochemical properties. The dual-electrode coulometric detection of the adduct showed high selectivity and sensitivity with a detection limit of 0.06 pmol. The proposed method is applicable to the determination of glutathione in biological specimens.