Distinctive interactions of oleic acid covered magnetic nanoparticles with saturated and unsaturated phospholipids in Langmuir monolayers

THABO J. MATSHAYA; ANABEL E. LANTERNA; ALEJANDRO M. GRANADOS; RUI W. M. KRAUSE; BRUNO MAGGIO; RAQUEL V. VICO

LANGMUIR

AMER CHEMICAL SOC

Lugar: Washington; Año: 2014 vol. 30 p. 5888 - 5896

0743-7463

The growing number of innovations in nanomedicine and nanobiotechnology are posing new challenges in understanding the full spectrum of interactions between nanomateriales and biomolecules at nanobiointerfaces. Although considerable achievements have been accomplished by in vivo applications many issues regarding the molecular nature of these interactions are far from being wellunderstood. In this work we evaluate the interaction of hydrophobic magnetic nanoparticles covered with a single layer of oleic acid with saturated and unsaturated phospholipids found in biomembranes through the use of Langmuir monolayers. We find distinctive interactions among the nanoparticles with saturated and unsaturated phospholipids that are reflected by both the compression isotherms and the surface topography of the films. The interaction of the magnetic nanoparticles with saturated lipids cause a noticeable reduction in the mean molecular area in the interfacial plane while the interaction with unsaturated lipids promote area expansion compared to the ideally mixed films. Besides, when liquidexpanded and liquidcondensed phases of the phospholipid/s coexist, the nanoparticles preferably partition to the liquid expanded phase thus impeding the coalescence of the condensed domains with increasing surface pressure. These findings show the existence of a sensitive compositiondependent surface regulation of the phospholipidnanoparticle interactions which enhance the biophysical relevance of understanding nanoparticle surface functionalization in relation to its interactions in biointerfaces constituted by defined types of biomolecules.