INVESTIGADORES
DISALVO Edgardo anibal
artículos
Título:
?Effect of Dipole Potential Variations On The Surface Charge Potential Of Lipid Membranes?
Autor/es:
LAIRION, F; DISALVO, E. A.
Revista:
JOURNAL OF PHYSICAL CHEMISTRY A
Editorial:
ACS publications
Referencias:
Año: 2009 vol. 113 p. 1438 - 1446
ISSN:
1089-5639
Resumen:
When the dipole potential of dimyristoylphosphatidylcholine (DMPC) monolayers was decreased, either by
the insertion of phloretin or by the elimination of carbonyl groups at the interphase, the surface charge potential
was displaced to lower negative values. At low ionic strength, the decrease of the negative charge density
can be ascribed to a different exposure of the phosphate to water, as there is a good correlation to an increase
in the area per lipid. At high ionic strength, the magnitude of the changes in the zeta potential produced by
the effects on the dipole potential was found to be dependent on the type of anions present in the subphase.
Differences between Cl- and ClO4- and ClO4
- were ascribed to the adsorption of anions according to their different
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.
were ascribed to the adsorption of anions according to their different
hydrations and polarizabilities. The influence of a low dipole potential on the anion adsorption can be ascribed
to a less positive image charge at the membrane interior, resulting from an increase in the hydrocarbon core
permittivity. This is congruent with the neutralization of interfacial dipoles and the area increase, as well as
with the decrease in packing of the hydrocarbon groups. Phloretin did not cause changes in the dipole potential
of dimyristoylphosphatidylethanolamine (DMPE), and in consequence, no effects on the zeta potential were
measured. It is concluded that changes in the inner water/hydrocarbon plane affect the electrostatic potential
measured in the outer plane of the polar headgroup region.