Interaction of magnetic nanoparticles with phospholipid films adsorbed at a liquid/liquid interface.

C. I. CÁMARA; L. M. YUDI

Sierra de la Ventana - Buenos Aires

Congreso; Sociedad Argentina de Biofísica. XLIII Reunión Anual 2014; 2014

Sociedad Argentina de Biofísica

Magnetic nanoparticles (MNPs) are widely used in biomedicine due to their versatility. The most common applications are in biosensor platforms, in drug or radio isotopes delivery, as a magnetic spacers of labeled cells, in tissue engineering, as a contrast agents in magnetic resonance studies and in hyperthermia based- therapies among others. Most applications are related with the interactions between MNPs and membranes models and, for this reason, the investigation of these interactions using different methodologies has gained great importance in the last years. In the present work we evaluate the effect of Co MNPs on the interfacial structure and permeability of distearoyl phosphatidic acid (DSPA) and disteroyl phosphatidyl glycerol (DPSG) films adsorbed at a water / 1,2-dichloroethane interface. The study is carried out employing cyclic voltametry (CV), electrochemical impedance spectroscopy (EIS), capacity curves and interfacial pressure ? area isotherms. DSPA and DSPG adsorb at the interface forming homogenous films and producing a blocking effect on the transfer process of tetra ethyl ammonium (TEA+), used as probe cation. In presence of Co MNPs this effect is reversed and the reversible transfer process for TEA+ is reestablished, in greater or lesser extent depending on the structuration of the film. Co-DSPA hybrid films have a homogeneous structure while Co-DSPG films present different domains. Moreover, the presence of Co on DSPA film modifies the partition coefficient of the organic electrolyte into the hydrocarbon layer.