Hybridation of different chiral separation techniques with ICP‐MS detection for the separation and determination of selenomethionine enantiomers: chiral speciation of selenized yeast

Abstract

Enantioseparation and determination of selenomethionine enantiomers in selenized yeast was investigated using chiral separation techniques based on different principles, coupled on-line to inductively coupled plasma mass spectrometry (ICP-MS) for selenium-specific detection. High performance liquid chromatography (HPLC) on a beta-cyclodestrin (beta-CD) column, cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC), gas chromatography (GC) on a Chirasil-L-Val column, and HPLC on a Chirobiotic T column have been investigated as the chiral separation techniques. For HPLC separation on the beta-CD column, and also for CD-MEKC, selenomethionine enantiomers were derivatized with NDA/CN(-). For chiral separation by GC, selenomethionine enantiomers were converted into their N-trifluoroacetyl (TFA)-O-alkyl esters. The developed hybridation methodologies are compared with respect to enantioselectivity, sensitivity and analysis time. The usefulness of the best-suited method [HPLC (Chirobiotic T)-ICP-MS] was demonstrated by its application to the successful chiral speciation of selenium and D-and L-selenomethionine content determination in selenized yeast.

Recent advances in amino acid analysis by capillary electrophoresis

“…Mendez et al [99] reported on the use of CD-modified MEKC for the separation of selenomethionine enantiomers when derivatized with naphthalene-2,3-dicarboxal-dehyde (NDA). A new analytical method was developed for enantioselective separation of DL-amino acids labeled with N-fluorenylmethoxycarbonyl-L-alanyl-N-carboxyanhydride (FMOC-L-Ala-NCA).…”

Determination of amino acids by micellar EKC: Recent advances in method development and novel applications to different matrices

“…This was the first report in which the use of a mixture of b-CD and sodium taurodeoxycholate as chiral selectors in combination was described for the optical resolution of selenomethionine and its derivatives by MEKC. The same authors also improved this method by coupling on-line CD-MEKC to inductively coupled plasma MS (ICP-MS) [116]. The latter approach was successfully applied to the chiral separation of selenium and D-and L-selenomethionine content determination in selenized yeast.…”

“…In a couple of reports Méndez et al [115,116] have described the optimal experimental conditions (10 mM 35 mM sodium borate pH 9.5 1 150 mM SDS Pharmaceutical products (2-Naphthoxy) acetyl chloride amino acids [119] borate, 30 mM phosphate buffer, pH 7.0, 30 mM b-CD, 50 mM taurodeoxycholate, and 50 mM SDS) to obtain the optical separation of racemic CBI-selenomethionine [115], the most active component in the formulation of nutritional supplements commercially available for human consumption. Since selenomethionine is chiral in nature and individual enantiomers usually play different roles in living organisms, optical resolution of selenomethionine into its D-and Lenantiomers is of great interest for nutritional purposes.…”

Derivatization trends in capillary electrophoresis: An update

“…Table 1 summarizes the recent developments in precapillary derivatization procedures. From Table 1 it becomes obvious that most procedures for derivatization of the amino function aim to increase the sensitivity of the assay of these compounds in various biological matrices and for various purposes, such as chiral separations [12][13][14][15][16][17][18]. Sometimes, the samples have been obtained by microdialysis [19,20].…”