(1)H-(13)C INEPT MAS NMR correlation experiments with (1)H-(1)H mediated magnetization exchange to probe organization in lipid biomembranes

J Magn Reson. 2006 Jun;180(2):210-21. doi: 10.1016/j.jmr.2006.02.013. Epub 2006 Mar 24.

Abstract

Two-dimensional (1)H-(13)C INEPT MAS NMR experiments utilizing a (1)H-(1)H magnetization exchange mixing period are presented for characterization of lipid systems. The introduction of the exchange period allows for structural information to be obtained via (1)H-(1)H dipolar couplings but with (13)C chemical shift resolution. It is shown that utilizing a RFDR recoupling sequence with short mixing times in place of the more standard NOE cross-relaxation for magnetization exchange during the mixing period allowed for the identification and separation of close (1)H-(1)H dipolar contacts versus longer-range inter-molecular (1)H-(1)H dipolar cross-relaxation. These 2D INEPT experiments were used to address both intra- and inter-molecular contacts in lipid and lipid/cholesterol mixtures.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Carbon Isotopes
  • Cholesterol / chemistry
  • Lipid Bilayers / chemistry*
  • Lipids / chemistry
  • Models, Theoretical
  • Nuclear Magnetic Resonance, Biomolecular / methods*

Substances

  • Carbon Isotopes
  • Lipid Bilayers
  • Lipids
  • Cholesterol