Deuterated phospholipids as nonperturbing components for Raman studies of biomembranes.

The deuterated phospholipid, 1,2-dipalmitoyl-d62-phosphatidylcholine is shown by Raman spectroscopic measurements to be useful for obtaining information concerning phospholipid conformation in complex phospholipid and lipidprotein mixtures. The Raman bands of the deuterated phospholipid are assigned, and the sensitivity of these vibrational modes to conformational changes in the bilayer is demonstrated. Deuteration of the alkyl chains reveals the CH vibrations of the head group. A change in these bands is observed at the melting temperature and is assigned to alteration of the glycerol backbone conformation upon melting.