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Updated: Mar 10, 2026

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Published on: February 10, 2022
Vitamin E Circular Dichroism Studies: Insights into Conformational Changes Induced by the Solvent's Polarity
Drew Marquardt1,2,3, Brad J Van Oosten4, Mikel Ghelfi5
1Department of Physics, Brock University, St. Catharines, ON L2S 3A1, Canada. marquardtdt@ornl.gov.
Abstract:
We used circular dichroism (CD) to study differences in CD spectra between α-, δ-, and methylated-α-tocopherol in solvents with different polarities. CD spectra of the different tocopherol structures differ from each other in intensity and peak locations, which can be attributed to chromanol substitution and the ability to form hydrogen bonds. In addition, each structure was examined in different polarity solvents using the Reichardt index-a measure of the solvent's ionizing ability, and a direct measurement of solvent-solute interactions. Differences across solvents indicate that hydrogen bonding is a key contributor to CD spectra at 200 nm. These results are a first step in examining the hydrogen bonding abilities of vitamin E in a lipid bilayer.
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