Specific binding of ethanol to cholesterol in organic solvents

Vladimir A. Daragan, Alexei M. Voloshin, Svetlana V. Chochina, Teodor N. Khazanovich, W. Gibson Wood, Nicolai A. Avdulov, Kevin H Mayo

Research output: Contribution to journalArticlepeer-review

13 Scopus citations


Although ethanol has been reported to affect cholesterol homeostasis in biological membranes, the molecular mechanism of action is unknown. Here, nuclear magnetic resonance (NMR) spectroscopic techniques have been used to investigate possible direct interactions between ethanol and cholesterol in various low dielectric solvents (acetone, methanol, isopropanol, DMF, DMSO, chloroform, and CCl4). Measurement of 13C chemical shifts, spin-lattice and multiplet relaxation times, as well as self-diffusion coefficients, indicates that ethanol interacts weakly, yet specifically, with the HC-OH moiety and the two flanking methylenes in the cyclohexanol ring of cholesterol. This interaction is most strong in the least polar-solvent carbon tetrachloride where the ethanol-cholesterol equilibrium dissociation constant is estimated to be 2 x 10-3 M. 13C-NMR spin-lattice relaxation studies allow insight into the geometry of this complex, which is best modeled with the methyl group of ethanol sandwiched between the two methylenes in the cyclohexanol ring and the hydroxyl group of ethanol hydrogen bonded to the hydroxyl group of cholesterol.

Original languageEnglish (US)
Pages (from-to)406-415
Number of pages10
JournalBiophysical journal
Issue number1
StatePublished - Jul 2000

Bibliographical note

Funding Information:
This research was generously supported by grants from the National Institutes of Health (AA 10806) and from the North Atlantic Treaty Organization (GRG-970039). NMR experiments were performed at the University of Minnesota High Field-NMR Laboratory.


Dive into the research topics of 'Specific binding of ethanol to cholesterol in organic solvents'. Together they form a unique fingerprint.

Cite this