Determination of D-penicillamine and tiopronin in human urine and serum by HPLC-FLD and CE-LIF with 1,3,5,7-tetramethyl-8-bromomethyl-difluoroboradiaza-s-indacene

Two rapid and sensitive analytical methods are developed for the determination of D-penicillamine (D-PEN) and tiopronin (TP) through high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). A boron-dipyrrolemethene (BODIPY) fluorescence labeling reagent, 1,3,5,7-tetramethyl-8-bromomethyl-difluoroboradiaza-s-indacene (TMMB-Br) was successfully applied to derivatize these two thiol drugs. Fluorescein was used as the internal standard (IS) for the quantification of D-PEN and TP in CE-LIF. The derivatization and separation conditions were optimized carefully. Under the optimum conditions, the HPLC and CE separation of D-PEN and TP could be achieved within 12 min. The limits of detection were as low as 2.0 nmol/L for HPLC-FLD and 0.47 nmol/L for CE-LIF. The drugs in human urine and serum samples were determined successfully, and the recoveries were 95.0–06.7% and 95.2–104.3%, respectively.