title: Influence of Alcohols on the Lateral Diffusion in Phospholipid Membranes.
abstract: The effects of hexanol and octanol on the lateral mobility of 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) bilayer are investigated by means of pulsed-gradient stimulated-echo NMR spectroscopy. Three distinct diffusions are identified for the DMPC/alcohol systems. They are ascribed to the water, the alcohol, and the lipid. We find that the presence of alcohols promotes the lipid diffusion process both in the liquid and in the interdigitated phases. Furthermore, using the Arrhenius approach, the activation energies are calculated. An explanation in terms of a free volume model, that takes into account also the observed increase of the activation energy in both phases, is proposed. The results obtained here are compared with those presented in our previous work on 1,2-palmitoyl-sn-glycero-3-phosphocholine (DPPC) in order to examine the dependence of the lipid translational diffusion process upon the membrane acyl chain length. A peculiar influence of alcohols on different membranes is found.
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Rifici
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: D'Angelo
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Crupi
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Branca
authors.affiliation: Institute for Physical Chemistry II, Ruhr-University Bochum , 44801 Bochum, Germany.
authors.forename: Valeria
authors.initials: V
authors.lastname: Conti Nibali
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Corsaro
authors.affiliation: Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina , 98166 Messina, Italy.
authors.forename: Ulderico
authors.initials: U
authors.lastname: Wanderlingh
mesh_terms: D004058:Diffusion; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry / Q000378:metabolism; D000441:Hexanols / Q000378:metabolism*; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism*; D008560:Membrane Fluidity; D000442:Octanols / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000441:Hexanols; D008051:Lipid Bilayers; D000442:Octanols; D010713:Phosphatidylcholines; D004134:Dimyristoylphosphatidylcholine