Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure

Article English OPEN
Yui, Y. ; Miyazaki, S. ; Ma, Y. ; Ohira, M. ; Fiehn, O. ; Ikegami, T. ; McCalley, D. V. ; Tanaka, N. (2016)

Separation of diastereomers of DL--tocopherol was studied by reversed-phase liquid chromatography using three types of stationary phases, polymeric ODS,polymeric C30, and monomeric ODS. Polymeric ODS stationary phase (Inertsil ODS-P, 3 mmID, 20 cm) was effective for the separation of the isomers created by the presence of three chiral centers on the alkyl chain of synthetic DL -tocopherol. Considerable improvement of the separation of isomers was observed on ODS-P phase at high pressure and at low temperature. Complete separation of four pairs of diastereomers was achieved at 12.0 oC, 536 bar, while three peaks were observed when the separation was carried out either at 12.0 oC at low pressure or at 20 oC at 488 bar. Higher temperature (30.0 oC) with the ODS-P phase resulted in only partial separation of the diastereomers even at high pressure. Only slight resolution was observed for the mixture of diastereomers with the C30 stationary phase (Inertsil C30) at 12.0 oC and 441 bar, although the stationary phase afforded greater resolution for - and -tocopherol than ODS-P. A monomeric C18 stationary phase did not show any separation at 12.0 oC and 463 bar. The results suggest that the binding site of the polymeric ODS-P phase is selective for flexible alkyl chains that provided the longest retention for the natural form, (R,R,R) form, and the enantiomer, (S,S,S) form, of DL--tocopherol.
  • References (21)
    21 references, page 1 of 3

    [2] F.J Rupérez, D Martı́n, E Herrera, C Barbas, Chromatographic analysis of α-tocopherol and related compounds in various matrices, J. Chromatogr. A 935 (2001) 45-69.

    [3] A. Kamal-Eldin, R. Andersson, A multivariate study of the correlation between tocopherol content and fatty acid composition in vegetable oils, J. Am. Oil Chem. Soc. 74 (1997) 375-380.

    [4] S. L. Abidi, T.L. Mounts, Normal phase high-performance liquid chromatography of tocopherols on polar phases, J. Liq. Chromatogr. Rel. Technol. 19 (1996) 509-520.

    [5] S. Strohschein, M. Pursch, D. Lubda, K. Albert, Shape Selectivity of C30 phases for RP-HPLC Separation of tocopherol isomers and correlation with MAS NMR data from suspended stationary phases, Anal. Chem. 70 (1998) 13-18.

    [6] A. A. Franke, C. M. Morrison, L. J. Custer, X. Li, J. F. Lai, Simultaneous analysis of circulating 25-hydroxy-vitamin D3, 25-hydroxy-vitamin D2, retinol, tocopherols, carotenoids, and oxidized and reduced coenzyme Q10 by high performance liquid chromatography with photo diode-array detection using C18 and C30 columns alone or in combination, J. Chromatogr. A 1301 (2013) 1-9.

    [7] N. Grebenstein, J. Frank, Rapid baseline-separation of all eight tocopherols and tocotrienols by reversed-phase liquid-chromatography with a solid-core pentafluorophenyl column and their sensitive quantification in plasma and liver, J. Chromatogr. A 1243 (2012) 39-46.

    [8] K. Okusa, Y. Iwasaki, I. Kuroda, S. Miwa, M. Ohira, T. Nagai, H. Mizobe, N. Gotoh, T. Ikegami, D. V. McCalley, N. Tanaka, Effect of pressure on the selectivity of polymeric C18 and C30 stationary phases in reversed-phase liquid chromatography. Increased separation of isomeric fatty acid methyl esters, triacylglycerols, and tocopherols at high pressure, J. Chromatogr. A 1339 (2014) 86-95.

    [9] O. Núñez, T. Ikegami, K. Miyamoto, N. Tanaka, Study of a monolithic silica capillary column coated with poly(octadecyl methacrylate) for the reversed-phase liquid chromatographic separation of some polar and non-polar compounds, J. Chromatogr. A 1175 (2007) 7-15.

    [10] Q. Duan, C. Liu, Z. Liu, Z. Zhou, W. Chen, Q. Wang, J. Crommen, Z. Jiang, Preparation and evaluation of a novel monolithic column containing double octadecyl chains for reverse-phase micro high performance liquid chromatography, J. Chromatogr. A 1345 (2014) 174-181.

    [11] K. A. Lippa, L. C. Sander, R. D. Mountain, Molecular dynamics simulations of alkylsilane stationary-phase order and disorder. 2. Effects of temperature and chain length, Anal. Chem., 77 (2005) 7862-7871.

  • Metrics
    No metrics available
Share - Bookmark