Effect of simple electrolytes on the hydrodynamic radius of polystyrene latex

Sasaki, Shinya

doi:10.1007/bf01410260

Cited by 19 publications

(14 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…31−33 Moreover, even after converting from intensity-weighted to surface-area-weighted hydrodynamic ⟨a⟩, the bare radius, corresponding to that for adsorption, is a few nanometers smaller than this hydrodynamic ⟨a⟩ since the hydrodynamic radius effectively includes a thin shell of water and screening counterions which move together with the droplets as they diffuse. 34 Taken together, corrections both for weighting and for hydrodynamic aspects would combine to reduce ⟨a⟩, leading to a more accurate determination of a larger measured total surface area for adsorption compared to what we have measured and reported using intensity-weighted hydrodynamic ⟨a⟩. Thus, for fixed ϕ, this lower value of ⟨a⟩ would increase the total surface area in the nanoemulsion compared to what we have used, and this would simply reduce all values of measured C s,f in the isotherm by a constant factor.…”

Section: ■ Discussionmentioning

confidence: 99%

Surfactant Partitioning in Nanoemulsions

Pagenkopp

Mason

2018

Langmuir

View full text Add to dashboard Cite

Using a fractionated silicone oil-in-water nanoemulsion (NEM), which has a high ratio of surface area-to-volume, we investigate surfactant partitioning between the bulk continuous phase and the adsorbed interfacial phase. By adjusting the droplet volume fraction of this fractionated NEM and by using gravimetric and electrical conductivity methods, we measure the bulk and the surface concentrations of an ionic surfactant (sodium dodecyl sulfate, SDS), thereby obtaining a raw adsorption isotherm of SDS on the interfaces of the nanodroplets. To overcome significant uncertainties in the total surface area of this nanoemulsion, we have also measured the macroscopic interfacial tension (IFT) of silicone oil in contact with aqueous SDS solutions using the du Noüy ring method. We then scale the surface concentration of this raw isotherm using an appropriate Gibbs derivative based on the IFT measurement, yielding an adjusted isotherm. We show that this adjusted isotherm can be described using a simple Langmuir equation. In addition, we show that a significant and non-negligible percentage of surfactant typically partitions to nanodroplet interfaces after high-flow-rate emulsification (HFRE) has transformed a microscale premix emulsion into a NEM. We develop a model for predicting the final bulk surfactant concentration after HFRE given the initial bulk surfactant concentration before HFRE. We show that this model can be used to predict trends for surfactant partitioning in polydisperse nanoemulsions after HFRE.

show abstract

Section: ■ Discussionmentioning

confidence: 99%

Surfactant Partitioning in Nanoemulsions

Pagenkopp

Mason

2018

Langmuir

View full text Add to dashboard Cite

show abstract

“…Our previously reported experimental results [2] showed no increase in the friction coefficient when exchanging hydrogen ions for the bulky counterions, such as quaternary ammonium ions. These data indicate that an electroviscous effect due to the friction of counterions, dragged by the ionized latex particle, cannot explain the observed phenomena.…”

Section: Introductionmentioning

confidence: 94%

“…Because of inadequate theoretical description of the friction properties of the particles mentioned above, the interpretation of the previous results [1][2][3] has been only qualitative. It is desirable to derive a substitute formula for the Stokes law in order to describe the friction coefficient of particles having the hairy surface or the more rigid than ordinary structure of the solvent at the surface.…”

Section: Introductionmentioning

confidence: 95%

“…Latex particles charged by sulfonic acid groups also showed an increase in the friction coefficient at low inonic strength, but no rough surface was detected. Water clusters having more rigid structure than the ordinary ones have been suggested to surround the latex particle [2]. The finding [2] that the friction coefficient decreases as the hydrogen ions are exchanged for the larger Na + or quarternary ammonium counterions indicates that the sticky structure in the water clusters at the surface is destroyed by an interference effect of bulky counterions on the cooperative hydrogen bonding among water molecules surrounding nonpolar polymer segments.…”

Section: Introductionmentioning

confidence: 97%

“…Recent dynamic light scattering studies of polymer latices have thrown light upon the fact that diffusion coefficients of latex particles decrease with raising the electrostatic surface potential, i. e., increasing the surface charge number of the particle or decreasing the ionic strength of solution [1,2]. Since this has been found for sufficiently low volume fractions of latices at which the inter-particle interactions could be neglected, the decrease in diffusion coefficient, D, should be attributed to an increase in dynamical friction coefficient of the particle as given by the Einstein relation,…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Friction coefficients of spheres having sticky or hairy surfaces

Sasaki

1985

Colloid & Polymer Sci

Self Cite

View full text Add to dashboard Cite

Abstract:The theoretical equations for friction coefficients of spheres having sticky or hairy surfaces are presented. In the present treatment, the sticky surface is represented by a higher viscosity of fluid in the surface layer and the hairy surface is assumed to have a porous structure. The friction coefficients are given as functions of the thickness of the surface layer, the fluid viscosity in the surface layer and the segmental density of hairy chains.

show abstract

Measuring particle concentration of multimodal synthetic reference materials and extracellular vesicles with orthogonal techniques: Who is up to the challenge?

Vogel

Savage

Muzard³

et al. 2021

J of Extracellular Vesicle

View full text Add to dashboard Cite

The measurement of physicochemical properties of polydisperse complex biological samples, for example, extracellular vesicles, is critical to assess their quality, for example, resulting from their production and isolation methods. The community is gradually becoming aware of the need to combine multiple orthogonal techniques to perform a robust characterization of complex biological samples. Three pillars of critical quality attribute characterization of EVs are sizing, concentration measurement and phenotyping. The repeatable measurement of vesicle concentration is one of the keychallenges that requires further efforts, in order to obtain comparable results by using different techniques and assure reproducibility. In this study, the performance of measuring the concentration of particles in the size range of 50-300 nm with complementary techniques is thoroughly investigated in a step-by step approach of incremental complexity. The six applied techniques include multi-angle dynamic light scattering (MADLS), asymmetric flow field flow fractionation coupled with multi-angle light scattering (AF4-MALS), centrifugal liquid sedimentation (CLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), and high-sensitivity nano flow cytometry (nFCM). To achieve comparability, monomodal samples and complex polystyrene mixtures were used as particles of metrological interest, in order to check the suitability of each technique in the size and concentration range of interest, and to develop reliable post-processing data protocols for the analysis. Subsequent complexity was introduced by testing liposomes as validation of the developed approaches with a known sample of physicochemical properties closer to EVs. Finally, the vesicles in EV containing plasma samples were analysed with all the tested techniques. The results presented here aim to shed some light into the requirements for the complex characterization of biological samples, as this is a critical need for quality assurance by the EV and regulatory community. Such efforts go with the view to contribute to both, setup reproducible and reliable characterization protocols, and comply with the Minimal Information for Studies of Extracellular Vesicles (MISEV) requirements.

show abstract

Effect of simple electrolytes on the hydrodynamic radius of polystyrene latex

Cited by 19 publications

References 7 publications

Surfactant Partitioning in Nanoemulsions

Surfactant Partitioning in Nanoemulsions

Friction coefficients of spheres having sticky or hairy surfaces

Measuring particle concentration of multimodal synthetic reference materials and extracellular vesicles with orthogonal techniques: Who is up to the challenge?

Contact Info

Product

Resources

About