Phase behavior of ascorbyl palmitate in DMPC monolayers and its projection to a possible drug delivery system of amiodarone

BENEDINI, L. ; ANTOLLINI, S.S.; FANANI, M.L.; PALMA, S.; MESSINA, P.; SCHULZ, P.

San Javier - Tucumán

Congreso; XLI Reunión Anual de la Sociedad Argentina de Biofísica; 2012

Sociedad Biofísica Argentina

Amiodarone (AMI) is a class III antiarrhythmic drug that shows adverse effects, some of them depending on its pharmaceutical injectable formulation and others by itself (1). The use of antioxidants is a theoretic form to repair or minimize the effects produced by AMI (1-2), and a liposomal formulation could avoid the effects produced by its cosolvents. Ascorbil palmitate (Asc16) could be used to reduce or avoid AMI side effects. The aim of this work is to develop liposomes formed by phospholipids and Asc16 for extrapolation of monolayers adsorption studies. The biophysical properties of both phospholipids-Asc16 liposomes system and phospholipids-Asc16-AMI liposomes systems have been studied by polarization generalized (GP). Monolayer experiments indicated that the phospholipid environment allows incorporation of Asc16 maintaining the properties of a fluid membrane. Addition of AMI to antioxidant liposomes (DMPC + Asc16) induced different effects depending on the Tt of the bilayer system: at temperatures below Tt all GP values were very similar; above Tt, GP values increased as a function of the AMI concentration, indicating a structuring effect in the liquid crystalline phase of the system. As long as we know, such systems were not reported previously in literature. Thus, we propose that binary liposomes composed of phospholipid and Asc16 can be considered as a system suitable for drug delivery function.