Analytical Sciences

Abstract − Analytical Sciences, 21(3), 253 (2005).

Chiral Speciation and Determination of DL-Selenomethionine Enantiomers on a Novel Chiral Ligand-Exchange Stationary Phase
Xiaojia HUANG,* Junde WANG,** Qiuquan WANG,* and Benli HUANG*
*Department of Chemistry & The MOE Key Laboratory of Analytical Sciences, Xiamen University, Xiamen 361005, China
**Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 161 Zhongshan Road, Dalian 116012, China
A new type of chiral ligand-exchange stationary phase (CLES) was successfully synthesized by treating silica gel with β-(3,4-epoxycyclohexyl)ethyltrimethoxy silane and opening the epoxy ring by L-isoleucine. The chiral speciation of DL-selenomethionine (DL-SeMet) by high-performance liquid chromatography (HPLC) with UV absorbance on the CLES column was studied. The influences of the contents of copper ion and methanol as well as the pH value in the mobile phase and temperature of the column on the efficiency of resolution of DL-SeMet were investigated in detail. DL-SeMet could be completely resolved within 40 min under the optimal operating conditions of 0.1 mmol/L Cu2+ at 0.05 mol/L KH2PO4 buffer (pH = 5.5) and 35°C temperature of the column. The limits of detection of D- and L-SeMet were 255 ppb and 286 ppb, respectively. This method was applied to determine the D- and L-enantiomers of DL-SeMet in real samples, such as selenized yeast powder and garlic.