Liquid-liquid phase coexistence in lipid membranes observed by natural abundance H-C solid-state NMR.

We demonstrate that 1H-13C solid-state MAS NMR is suitable to detect liquid disordered/liquid ordered phase coexistence in a DOPC/DPPC/cholesterol mixture with natural abundance of isotopes as an alternative to 2H NMR. Such methodology is potentially applicable to study lipid phase coexistence phenomena in biological matter with high lipid content, e.g. lung surfactant or myelin, for which isotopic labeling is not possible.