Chiral speciation and determination of selenomethionine enantiomers in selenized yeast by HPLC-ICP-MS using a teicoplanin-based chiral stationary phase

Abstract

Chiral separation of underivatized selenoaminoacids enantiomers by high performance liquid chromatography (HPLC) on a glycopeptide antibiotic teicoplanin-based chiral stationary phase (Chirobiotic T) was investigated. The effect of methanol content, pH and ionic strength of the mobile phase on retention and resolution of the enantiomers was examined to optimize the chromatographic conditions. Underivatized DL-selenomethionine and DL-selenoethionine enantiomers were completely resolved within 8 min using a 2% (v/v) methanol–water (unbuffered) mobile phase delivered at 1 mL min−1. Very good selectivity and excellent detection limits of 1.9 µg L−1 (0.8 µg L−1 as Se) for each DL-selenomethionine enantiomer were obtaining by on-line coupling the chiral HPLC separation with selenium-specific detection by inductively coupled plasma quadrupole mass spectrometry (ICP-MS). The HPLC-ICP-MS method was successfully applied to the chiral speciation and determination of D- and L- selenomethionine enantiomers in real samples of selenized yeast.