Hydration studies on lipid membranes: Classification of water molecules near the bilayer in gel and liquid phase.

L.M. ALARCÓN; M.A. MORINI; M.B. SIERRA; V.I. PEDRONI; G.A. APPIGNANESI.; E.A. DISALVO

Santiago del Estero

Congreso; XLIV Reunión Anual SAB 2015; 2015

CITSE-UNSE

We studiedthe hydration of membranes composedof dipalmitoylphosphatidylcholine (DPPC) lipid molecules, revealing that the water molecules do not only moisturize the polar groups of the lipids, but alsopenetrate through alkane chains of such molecules. Tocharacterize these lipid systems and comparethem with other systems as hydrophobicand hydrophilic monolayers we studydifferent parameters, such as densityfluctuation, residence times and orientation of thewater molecules on the surface ofthe monolayer, inaddition to typical parameters in lipid membranes asarea per lipid and number ofwater molecules per lipid. Furthermore,we discriminate water molecules surrounding the lipid membrane, ranking themaccording to their distances (and residence times) on different atoms composingthe lipid bilayer. These studies were conducted both in liquid phase and gelphase.