Shape selectivity of C30 phases for RP-HPLC separation of tocopherol isomers and correlation with MAS NMR data from suspended stationary phases

Analytical Chemistry
S StrohscheinKlaus Albert

Abstract

Vitamin E (tocopherol) acts in various organisms as the main free radical scavenger. This capacity, which is enhanced by the synergetic effect of vitamin C and carotenes, points to a possible application as anti-tumor agent in chemotherapy. There are several isomeric forms, namely alpha-, beta-, gamma-, and delta-tocopherol, having different antioxidative abilities, with alpha-tocopherol being the most biologically active. Using methanol as eluent and a C30 stationary phase, we achieved complete separation of alpha-, beta-, gamma-, and delta-tocopherol and alpha-tocopherol acetate by RP-HPLC within 14 min. Detection was performed by UV and 1H NMR spectroscopy. The advantage of NMR is the possibility of structural identification of chromatographic peaks. Also, coeluting peaks are easily recognized. The enhanced shape recognition of the C30 phase has been attributed to the high order of the alkyl chains of the stationary phase. This has, so far, been proven by solid-state NMR spectroscopy. We now introduce the technique of 13C MAS NMR spectroscopy of suspended stationary phases. The resulting NMR spectra reveal that, in the presence of weak eluents, like methanol, the overall high order of the C30 chains is slightly altered, wher...Continue Reading

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Citations

Dec 4, 2004·Analytical and Bioanalytical Chemistry·Catherine A RimmerStephen A Wise
Apr 14, 2005·Analytical and Bioanalytical Chemistry·Lane C SanderStephen A Wise
Sep 25, 2004·Journal of Chromatography. a·Olivia Maria Cholewa
Jul 13, 2000·Journal of Chromatography. a·L C SanderM Pursch
Jan 5, 2002·Journal of Chromatography. a·F J RupérezC Barbas
Oct 20, 1999·Journal of Chromatography. a·K Albert
Feb 26, 2003·Journal of Colloid and Interface Science·Mukundan ChakrapaniP A Rikvold
Jun 13, 2012·Journal of Agricultural and Food Chemistry·Catherine A RimmerJames H Yen
Aug 5, 2005·Chemical & Pharmaceutical Bulletin·Wataru SakaneCarmenza Duque
Aug 18, 2010·Journal of Separation Science·Abul K MallikHirotaka Ihara
Oct 18, 2019·Critical Reviews in Food Science and Nutrition·Supradip SahaKaushik Banerjee
Jun 13, 2020·Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences·Lysiane BouletVéronique Ducros
Oct 16, 2004·Journal of Chromatography. a·Anna Gliszczyńska-Swigło, Ewa Sikorska
Aug 7, 2018·Analytical Chemistry·F H M van ZelstA P M Kentgens
Jun 29, 1999·Analytical Chemistry·R K Gilpin, L A Pachla
Feb 3, 2005·Journal of Agricultural and Food Chemistry·Karsten PutzbachGregory G Dolnikowski

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