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Surface deposition and phase behavior of oppositely charged polyion-surfactant ion complexes. Delivery of silicone oil emulsions to hydrophobic and hydrophilic surfaces.

Clauzel M, Johnson ES, Nylander T, Panandiker RK, Sivik MR, Piculell L - ACS Appl Mater Interfaces (2011)

Bottom Line: The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl.The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers.For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

View Article: PubMed Central - PubMed

Affiliation: Physical Chemistry, Kemicentrum, Lund University, Box 124, SE-221 00, Lund, Sweden. maryline.clauzel@gmail.com

ABSTRACT
The adsorption from mixed polyelectrolyte-surfactant solutions at hydrophobized silica surfaces was investigated by in situ -ellipsometry, and compared to similar measurements for hydrophilic silica surfaces. Three synthetic cationic copolymers of varying hydrophobicity and one cationic hydroxyethyl cellulose were compared in mixtures with the anionic surfactant sodium dodecylsulfate (SDS) in the absence or presence of a dilute silicone oil emulsion. The adsorption behavior was mapped while stepwise increasing the concentration of SDS to a polyelectrolyte solution of constant concentration. The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl. An adsorbed layer remained after complete exchange of the polyelectrolyte/surfactant solution for aqueous NaCl. In most cases, there was a codeposition of silicone oil droplets, if such droplets were present in the formulation before dilution. The overall features of the deposition were similar at hydrophobic and hydrophilic surfaces, but there were also notable differences. SDS molecules adsorbed selectively at the hydrophobized silica surface, but not at the hydrophilic silica, which influenced the coadsorption of the cationic polymers. The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers. For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

No MeSH data available.


Related in: MedlinePlus

Effect of diluting a formulation of 100 ppm cat-HEC, 20 mM SDS and 1 mM NaCl, without (filled circles) and with (open circles) 400 ppm silicone emulsion on the adsorption at a) hydrophilic and b) hydrophobized silica. Time zero corresponds to the beginning of dilution with 1 mM NaCl at a rate of 5 mL/min, for a cuvette volume of 5 mL and a stirring rate of 300 rpm.
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fig6: Effect of diluting a formulation of 100 ppm cat-HEC, 20 mM SDS and 1 mM NaCl, without (filled circles) and with (open circles) 400 ppm silicone emulsion on the adsorption at a) hydrophilic and b) hydrophobized silica. Time zero corresponds to the beginning of dilution with 1 mM NaCl at a rate of 5 mL/min, for a cuvette volume of 5 mL and a stirring rate of 300 rpm.

Mentions: Figure 6 shows the results for cat-HEC with SDS when the solution was diluted from a surfactant concentration of 20 mM, far above crediss. Here, there was no initial adsorption to hydrophilic silica, but a thin adsorbed layer developed immediately on hydrophobized silica. Diluting the bulk solution led to a net increase in deposition after a transient maximum that was quite weak except for the mixture including emulsion at hydrophobized silica. As in Figure 5, the net increase in adsorbed amount upon further dilution, from the mixture including emulsion was significant on hydrophilic silica, but insignificant on hydrophobized silica.


Surface deposition and phase behavior of oppositely charged polyion-surfactant ion complexes. Delivery of silicone oil emulsions to hydrophobic and hydrophilic surfaces.

Clauzel M, Johnson ES, Nylander T, Panandiker RK, Sivik MR, Piculell L - ACS Appl Mater Interfaces (2011)

Effect of diluting a formulation of 100 ppm cat-HEC, 20 mM SDS and 1 mM NaCl, without (filled circles) and with (open circles) 400 ppm silicone emulsion on the adsorption at a) hydrophilic and b) hydrophobized silica. Time zero corresponds to the beginning of dilution with 1 mM NaCl at a rate of 5 mL/min, for a cuvette volume of 5 mL and a stirring rate of 300 rpm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211372&req=5

fig6: Effect of diluting a formulation of 100 ppm cat-HEC, 20 mM SDS and 1 mM NaCl, without (filled circles) and with (open circles) 400 ppm silicone emulsion on the adsorption at a) hydrophilic and b) hydrophobized silica. Time zero corresponds to the beginning of dilution with 1 mM NaCl at a rate of 5 mL/min, for a cuvette volume of 5 mL and a stirring rate of 300 rpm.
Mentions: Figure 6 shows the results for cat-HEC with SDS when the solution was diluted from a surfactant concentration of 20 mM, far above crediss. Here, there was no initial adsorption to hydrophilic silica, but a thin adsorbed layer developed immediately on hydrophobized silica. Diluting the bulk solution led to a net increase in deposition after a transient maximum that was quite weak except for the mixture including emulsion at hydrophobized silica. As in Figure 5, the net increase in adsorbed amount upon further dilution, from the mixture including emulsion was significant on hydrophilic silica, but insignificant on hydrophobized silica.

Bottom Line: The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl.The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers.For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

View Article: PubMed Central - PubMed

Affiliation: Physical Chemistry, Kemicentrum, Lund University, Box 124, SE-221 00, Lund, Sweden. maryline.clauzel@gmail.com

ABSTRACT
The adsorption from mixed polyelectrolyte-surfactant solutions at hydrophobized silica surfaces was investigated by in situ -ellipsometry, and compared to similar measurements for hydrophilic silica surfaces. Three synthetic cationic copolymers of varying hydrophobicity and one cationic hydroxyethyl cellulose were compared in mixtures with the anionic surfactant sodium dodecylsulfate (SDS) in the absence or presence of a dilute silicone oil emulsion. The adsorption behavior was mapped while stepwise increasing the concentration of SDS to a polyelectrolyte solution of constant concentration. The effect on the deposition of dilution of the bulk solution in contact with the surface was also investigated by gradual replacement of the bulk solution with 1 mM aqueous NaCl. An adsorbed layer remained after complete exchange of the polyelectrolyte/surfactant solution for aqueous NaCl. In most cases, there was a codeposition of silicone oil droplets, if such droplets were present in the formulation before dilution. The overall features of the deposition were similar at hydrophobic and hydrophilic surfaces, but there were also notable differences. SDS molecules adsorbed selectively at the hydrophobized silica surface, but not at the hydrophilic silica, which influenced the coadsorption of the cationic polymers. The largest amount of deposited material after dilution was found for hydrophilic silica and for the least-hydrophobic cationic polymers. For the least-hydrophobic polyions, no significant codeposition of silicone oil was detected at hydrophobized silica after dilution if the initial SDS concentration was high.

No MeSH data available.


Related in: MedlinePlus