Rheological properties of a two phase lipid monolayer at the air/water interface. Effect of the composition of the mixture

N. WILKE , F. VEGA MERCADO Y B. MAGGIO

AMER CHEMICAL SOC

Lugar: USA; Año: 2010 vol. 26 p. 11050 - 11050

any biologically relevant monolayers show coexistence of discrete domains of a long-range ordered condensedphase dispersed in a continuous, disordered, liquid-expanded phase. In this work, we determined the viscous and elasticcomponents of the compressibility modulus and the shear viscosity of monolayers exhibiting phase coexistence with theaim at elucidating the contribution of each phase to the observed monolayer mechanical properties. To this purpose,mixed monolayers with different proportions of distearoylphosphatidylcholine (DSPC) and dimyristoylphosphatidylcholine(DMPC) were prepared and their rheological properties were analyzed. The relationship between the phasediagram of the mixture at 10 mN m-1 and the rheological properties was studied. We found that the monolayer shearviscosity is highly dependent on the presence of domains and on the domain density. In turn, the monolayercompressibility is only influenced by the presence of