Partitioning behavior of silica in the PEG/dextran/H2O aqueous biphasic system

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The partitioning behavior of silica particles was investigated in the polyethylene glycol (PEG)/dextran/water system. It was found that both surfactant/solid electrostatic interactions and polymer/solid hydrogen bonding interactions played important roles in determining the solids distribution. Silica partition was highly pH-dependent; the solids transferred from the top PEG-rich phase to the bottom dextran-rich phase with increase in pH, but the particles moved back to the top phase above pH 12. This behavior was interpreted in terms of the pH dependence of PEG/SiO2 hydrogen bonding interaction and the weak acidity of dextran. The addition of sodium dodecylsulfate resulted in the preferential distribution of the particles to the bottom phase above pH 2. In contrast, in the presence of dodecyltrimethylammonium bromide, the solids stayed in the top phase below pH 6; with an increase in pH, the particles transferred from the top phase to the interface, then to the bottom phase. These surfactant effects are attributable to the electrostatic interaction between the surfactants and the solid surface.

Original languageEnglish (US)
Pages (from-to)45-54
Number of pages10
JournalColloids and Surfaces A: Physicochemical and Engineering Aspects
Volume226
Issue number1-3
DOIs
StatePublished - Sep 30 2003

Fingerprint

dextrans
Dextran
Dextrans
Silicon Dioxide
Polyethylene glycols
glycols
polyethylenes
Silica
silicon dioxide
Surface-Active Agents
Surface active agents
Coulomb interactions
surfactants
Hydrogen bonds
interactions
electrostatics
Acidity
hydrogen
acidity
Polymers

All Science Journal Classification (ASJC) codes

  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry

Cite this

@article{7afb7f48fd3c4c919c9d343530d1e482,
title = "Partitioning behavior of silica in the PEG/dextran/H2O aqueous biphasic system",
abstract = "The partitioning behavior of silica particles was investigated in the polyethylene glycol (PEG)/dextran/water system. It was found that both surfactant/solid electrostatic interactions and polymer/solid hydrogen bonding interactions played important roles in determining the solids distribution. Silica partition was highly pH-dependent; the solids transferred from the top PEG-rich phase to the bottom dextran-rich phase with increase in pH, but the particles moved back to the top phase above pH 12. This behavior was interpreted in terms of the pH dependence of PEG/SiO2 hydrogen bonding interaction and the weak acidity of dextran. The addition of sodium dodecylsulfate resulted in the preferential distribution of the particles to the bottom phase above pH 2. In contrast, in the presence of dodecyltrimethylammonium bromide, the solids stayed in the top phase below pH 6; with an increase in pH, the particles transferred from the top phase to the interface, then to the bottom phase. These surfactant effects are attributable to the electrostatic interaction between the surfactants and the solid surface.",
author = "X. Zeng and K. Osseo-Asare",
year = "2003",
month = "9",
day = "30",
doi = "10.1016/S0927-7757(03)00354-6",
language = "English (US)",
volume = "226",
pages = "45--54",
journal = "Colloids and Surfaces A: Physicochemical and Engineering Aspects",
issn = "0927-7757",
publisher = "Elsevier",
number = "1-3",

}

Partitioning behavior of silica in the PEG/dextran/H2O aqueous biphasic system. / Zeng, X.; Osseo-Asare, K.

In: Colloids and Surfaces A: Physicochemical and Engineering Aspects, Vol. 226, No. 1-3, 30.09.2003, p. 45-54.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Partitioning behavior of silica in the PEG/dextran/H2O aqueous biphasic system

AU - Zeng, X.

AU - Osseo-Asare, K.

PY - 2003/9/30

Y1 - 2003/9/30

N2 - The partitioning behavior of silica particles was investigated in the polyethylene glycol (PEG)/dextran/water system. It was found that both surfactant/solid electrostatic interactions and polymer/solid hydrogen bonding interactions played important roles in determining the solids distribution. Silica partition was highly pH-dependent; the solids transferred from the top PEG-rich phase to the bottom dextran-rich phase with increase in pH, but the particles moved back to the top phase above pH 12. This behavior was interpreted in terms of the pH dependence of PEG/SiO2 hydrogen bonding interaction and the weak acidity of dextran. The addition of sodium dodecylsulfate resulted in the preferential distribution of the particles to the bottom phase above pH 2. In contrast, in the presence of dodecyltrimethylammonium bromide, the solids stayed in the top phase below pH 6; with an increase in pH, the particles transferred from the top phase to the interface, then to the bottom phase. These surfactant effects are attributable to the electrostatic interaction between the surfactants and the solid surface.

AB - The partitioning behavior of silica particles was investigated in the polyethylene glycol (PEG)/dextran/water system. It was found that both surfactant/solid electrostatic interactions and polymer/solid hydrogen bonding interactions played important roles in determining the solids distribution. Silica partition was highly pH-dependent; the solids transferred from the top PEG-rich phase to the bottom dextran-rich phase with increase in pH, but the particles moved back to the top phase above pH 12. This behavior was interpreted in terms of the pH dependence of PEG/SiO2 hydrogen bonding interaction and the weak acidity of dextran. The addition of sodium dodecylsulfate resulted in the preferential distribution of the particles to the bottom phase above pH 2. In contrast, in the presence of dodecyltrimethylammonium bromide, the solids stayed in the top phase below pH 6; with an increase in pH, the particles transferred from the top phase to the interface, then to the bottom phase. These surfactant effects are attributable to the electrostatic interaction between the surfactants and the solid surface.

UR - http://www.scopus.com/inward/record.url?scp=0141992167&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0141992167&partnerID=8YFLogxK

U2 - 10.1016/S0927-7757(03)00354-6

DO - 10.1016/S0927-7757(03)00354-6

M3 - Article

AN - SCOPUS:0141992167

VL - 226

SP - 45

EP - 54

JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects

JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects

SN - 0927-7757

IS - 1-3

ER -