ASCORBYL PALMITATE INTERACTION WITH PHOSPHOLIPID MONOLAYERS: ELECTROSTATIC AND RHEOLOGICAL PREPONDERANCY

MOTTOLA, MILAGRO; WILKE, N.; BENEDINI, LUCIANO; RAFAEL GUSTAVO OLIVEIRA; FANANI, M. L.

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2013 vol. 1828 p. 2496 - 2496

scorbyl palmitate (ASC16) is an anionic amphiphilic molecule of pharmacological interest due to its antioxidant properties. We found that ASC16 strongly interacted with model membranes. ASC16 penetrated phospholipid monolayers, with a cut off near the theoretical surface pressure limit. The presence of a lipid film at the interface favored ASC16 insertion compared with a bare air/water surface. The adsorption and penetration time curves showed a biphasic behavior: the first rapid peak evidenced a fast adsorption of charged ASC16 molecules to the interface that promoted a lowering of surface pH, thus partially neutralizing and compacting the film. The second rise represented an approach to the equilibrium between the ASC16 molecules in the subphase and the surface monolayer, whose kinetics depended on the ionization state of the film. Based on the Langmuir DMPC+ASC16 monolayer data, we estimated an ASC16 partition coefficient to DMPC monolayers of 1.5x10 rheological properties of the