Direct measurements of surface forces between bilayers of double-chained quaternary ammonium acetate and bromide surfactants

Pashley, Richard M.; McGuiggan, Patricia; Ninham, Barry W.; Brady, James E.; Evans, D. F.

doi:10.1021/j100399a037

Cited by 172 publications

(146 citation statements)

References 4 publications

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“…On the other hand, for bromide and other halide anions the force measurements require for fitting the postulation of an extra, chemical, ion binding. The differences between the two kinds of measured forces are an order of magnitude [41].…”

Section: Ion Binding and Bilayer Forcesmentioning

confidence: 97%

Two sides of the coin. Part 1. Lipid and surfactant self-assembly revisited

Ninham

Larsson

Nostro

2017

Colloids and Surfaces B: Biointerfaces

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a b s t r a c tHofmeister, specific ion effects, hydration and van der Waals forces at and between interfaces are factors that determine curvature and microstructure in self assembled aggregates of surfactants and lipids; and in microemulsions. Lipid and surfactant head group interactions and between aggregates vary enormously and are highly specific. They act on the hydrophilic side of a bilayer, micelle or other self assembled aggregate. It is only over the last three decades that the origin of Hofmeister effects has become generally understood. Knowledge of their systematics now provides much flexibility in designing nanostructured fluids.The other side of the coin involves equally specific forces. These (opposing) forces work on the hydrophobic side of amphiphilic interfaces. They are due to the interaction of hydrocarbons and other "oils" with hydrophobic tails of surfactants and lipids. The specificity of oleophilic solutes in microemulsions and lipid membranes provides a counterpoint to Hofmeister effects and hydration. Together with global packing constraints these effects determine microstructure.Another factor that has hardly been recognised is the role of dissolved gas. This introduces further, qualitative changes in forces that prescribe microstructure.The systematics of these effects and their interplay are elucidated. Awareness of these competing factors facilitates formulation of self assembled nanostructured fluids. New and predictable geometries that emerge naturally provide insights into a variety of biological phenomena like anaesthetic and pheromone action and transmission of the nervous impulse (see Part 2).

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Section: Ion Binding and Bilayer Forcesmentioning

confidence: 97%

Two sides of the coin. Part 1. Lipid and surfactant self-assembly revisited

Ninham

Larsson

Nostro

2017

Colloids and Surfaces B: Biointerfaces

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“…Distances out of this scope will probably result in disagreement due to hydration forces [166]; (2) multivalent electrolytes with high concentration may result in the failure of DLVO. This is possibly caused by the reduction of electrostatic force and the prevalence of dispersion forces [167,168]; and (3) there are other short range non-DLVO interactions [169,170].…”

Section: Dlvomentioning

confidence: 99%

Heteroaggregation of nanoparticles with biocolloids and geocolloids

Wang

Adeleye

Huang

et al. 2015

Advances in Colloid and Interface Science

170

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The application of nanoparticles has raised concern over the safety of these materials to human health and the ecosystem. After release into an aquatic environment, nanoparticles are likely to experience heteroaggregation with biocolloids, geocolloids, natural organic matter (NOM) and other types of nanoparticles. Heteroaggregation is of vital importance for determining the fate and transport of nanoparticles in aqueous phase and sediments. In this article, we review the typical cases of heteroaggregation between nanoparticles and biocolloids and/or geocolloids, mechanisms, modeling, and important indicators used to determine heteroaggregation in aqueous phase. The major mechanisms of heteroaggregation include electric force, bridging, hydrogen bonding, and chemical bonding. The modeling of heteroaggregation typically considers DLVO, X-DLVO, and fractal dimension. The major indicators for studying heteroaggregation of nanoparticles include surface charge measurements, size measurements, observation of morphology of particles and aggregates, and heteroaggregation rate determination. In the end, we summarize the research challenges and perspective for the heteroaggregation of nanoparticles, such as the determination of α hetero values and heteroaggregation rates; more accurate analytical methods instead of DLS for heteroaggregation measurements; sensitive analytical techniques to measure low concentrations of nanoparticles in heteroaggregation systems; appropriate characterization of NOM at the molecular level to understand the structures and fractionation of NOM; effects of different types, concentrations, and fractions of NOM on the heteroaggregation of nanoparticles; the quantitative adsorption and desorption of NOM onto the surface of nanoparticles and heteroaggregates; and a better understanding of the fundamental mechanisms and modeling of heteroaggregation in natural water which is a complex system containing NOM, nanoparticles, biocolloids and geocolloids.

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“…Experiments demonstrate that the potential in the double layer decays with distance perpendicular to the bilayer as predicted from Gouy-Chapman theory (e.g. Looseley-Millman, Rand & Parsegian, 1979;Marra, 1986;Pashley, McGuiggan, Ninham, Brady & Evans 1986;Winiski, Eisenberg & McLaughlin, 1987); the decay is approximately exponential with a space constant equal to the Debye length, which is less than 1 nm when the salt concentration is greater than 041 M. Thus, our results are consistent with the hypothesis that the binding site is less than 1 nm from the surface of the plasmalemma (or granule) membrane.…”

Section: Discussionmentioning

confidence: 73%

Cations that alter surface potentials of lipid bilayers increase the calcium requirement for exocytosis in sea urchin eggs.

McLaughlin

Whitaker

1988

The Journal of Physiology

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SUMMARY1. We examined the effects of cations that bind to phospholipid bilayers on the calcium requirement for exocytosis in vitro.2. Tetracaine and trifluoperazine, two monovalent cations that bind hydrophobically to lipid bilayers, decreased the c-potential of lipid vesicles with a phospholipid composition similar to sea urchin plasma membranes; the decrease in the magnitude of the negative c-potential was consistent with the GouyChapman-Stern theory.3. Trifluoperazine and tetracaine also increased the concentration of calcium required to produce half-maximal exocytosis (Ca50) in isolated fragments of plasma membranes from sea urchin eggs. 4. The effects of trifluoperazine and tetracaine on the Ca50 of egg fragments can be explained quantitatively from the c-potential data obtained with phospholipid vesicles if we assume the calcium binding sites responsible for triggering exocytosis lie within a Debye length (< 1 nm) of the surface of the plasma membranes, such that the concentration of calcium at the sites is affected by the surface potential of the membrane.5. The divalent cation magnesium, which binds specifically to the phosphate group of lipids, affected Ca50 in a manner that can also be explained quantitatively from its effects on the a-potential of phospholipid vesicles.6. The polyvalent cation neomycin, which adsorbs to the lipid phosphatidylinositol 4,5-bisphosphate with high affinity, also binds co-operatively to phosphatidylinositol; its effect on Ca50 can be explained quantitatively from its effects on the c-potential of vesicles containing the latter lipid.7. A decrease in the ionic strength increases the magnitude of the surface potential of membranes; the effect of ionic strength on Ca50 can be explained qualitatively from its effect on the a-potential of phospholipid vesicles.8. All our results are consistent with the hypothesis that calcium binding sites lie within a Debye length of the plasma membrane; they also indicate that drugs with specific, high-affinity sites may affect exocytosis by a non-specific mechanism.

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Direct measurements of surface forces between bilayers of double-chained quaternary ammonium acetate and bromide surfactants

Cited by 172 publications

References 4 publications

Two sides of the coin. Part 1. Lipid and surfactant self-assembly revisited

Two sides of the coin. Part 1. Lipid and surfactant self-assembly revisited

Heteroaggregation of nanoparticles with biocolloids and geocolloids

Cations that alter surface potentials of lipid bilayers increase the calcium requirement for exocytosis in sea urchin eggs.

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