Osmolytic co-solute perturbing the surface enhancement of halide ions

Xiaohu Li, George C Schatz

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We have investigated the variation in the surface binding free energy with the choice of halide ion, F-, Cl-, Br-, and I-, in water-glycerol binary mixtures with varying glycerol concentrations using umbrella sampling with a polarizable force field. We have found that halide surface adsorption is significantly perturbed by glycerol. At no or low glycerol concentration, the surface preference follows the Hofmeister series (I- > Br- > Cl- > F -). However, at the highest concentration, Br- is preferentially stabilized. Decomposition of the free energy indicates that the halide surface adsorption is dominated by enthalpy and, specifically, by the solvent-solvent polarization interaction. The differences in this interaction between the chaotropic halides are reduced by glycerol addition, which is in line with a recent measurement of the solvent excess enthalpy for the same systems studied here. Moreover, our calculations indicate that the effect of an osmolyte (glycerol) on surface ion concentrations parallels the known effect of osmolytes on protein folding.

Original languageEnglish
Pages (from-to)2885-2889
Number of pages5
JournalJournal of Physical Chemistry Letters
Volume4
Issue number17
DOIs
Publication statusPublished - Sep 5 2013

Fingerprint

glycerols
Glycerol
halides
solutes
Ions
augmentation
ions
Free energy
Enthalpy
enthalpy
free energy
Protein folding
Adsorption
adsorption
ion concentration
Binary mixtures
folding
field theory (physics)
binary mixtures
sampling

Keywords

  • glycerol
  • Hofmeister series
  • interface
  • PMF
  • polarization

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Osmolytic co-solute perturbing the surface enhancement of halide ions. / Li, Xiaohu; Schatz, George C.

In: Journal of Physical Chemistry Letters, Vol. 4, No. 17, 05.09.2013, p. 2885-2889.

Research output: Contribution to journalArticle

@article{061047807d7b43b29a67084e929ebf8f,
title = "Osmolytic co-solute perturbing the surface enhancement of halide ions",
abstract = "We have investigated the variation in the surface binding free energy with the choice of halide ion, F-, Cl-, Br-, and I-, in water-glycerol binary mixtures with varying glycerol concentrations using umbrella sampling with a polarizable force field. We have found that halide surface adsorption is significantly perturbed by glycerol. At no or low glycerol concentration, the surface preference follows the Hofmeister series (I- > Br- > Cl- > F -). However, at the highest concentration, Br- is preferentially stabilized. Decomposition of the free energy indicates that the halide surface adsorption is dominated by enthalpy and, specifically, by the solvent-solvent polarization interaction. The differences in this interaction between the chaotropic halides are reduced by glycerol addition, which is in line with a recent measurement of the solvent excess enthalpy for the same systems studied here. Moreover, our calculations indicate that the effect of an osmolyte (glycerol) on surface ion concentrations parallels the known effect of osmolytes on protein folding.",
keywords = "glycerol, Hofmeister series, interface, PMF, polarization",
author = "Xiaohu Li and Schatz, {George C}",
year = "2013",
month = "9",
day = "5",
doi = "10.1021/jz4014695",
language = "English",
volume = "4",
pages = "2885--2889",
journal = "Journal of Physical Chemistry Letters",
issn = "1948-7185",
publisher = "American Chemical Society",
number = "17",

}

TY - JOUR

T1 - Osmolytic co-solute perturbing the surface enhancement of halide ions

AU - Li, Xiaohu

AU - Schatz, George C

PY - 2013/9/5

Y1 - 2013/9/5

N2 - We have investigated the variation in the surface binding free energy with the choice of halide ion, F-, Cl-, Br-, and I-, in water-glycerol binary mixtures with varying glycerol concentrations using umbrella sampling with a polarizable force field. We have found that halide surface adsorption is significantly perturbed by glycerol. At no or low glycerol concentration, the surface preference follows the Hofmeister series (I- > Br- > Cl- > F -). However, at the highest concentration, Br- is preferentially stabilized. Decomposition of the free energy indicates that the halide surface adsorption is dominated by enthalpy and, specifically, by the solvent-solvent polarization interaction. The differences in this interaction between the chaotropic halides are reduced by glycerol addition, which is in line with a recent measurement of the solvent excess enthalpy for the same systems studied here. Moreover, our calculations indicate that the effect of an osmolyte (glycerol) on surface ion concentrations parallels the known effect of osmolytes on protein folding.

AB - We have investigated the variation in the surface binding free energy with the choice of halide ion, F-, Cl-, Br-, and I-, in water-glycerol binary mixtures with varying glycerol concentrations using umbrella sampling with a polarizable force field. We have found that halide surface adsorption is significantly perturbed by glycerol. At no or low glycerol concentration, the surface preference follows the Hofmeister series (I- > Br- > Cl- > F -). However, at the highest concentration, Br- is preferentially stabilized. Decomposition of the free energy indicates that the halide surface adsorption is dominated by enthalpy and, specifically, by the solvent-solvent polarization interaction. The differences in this interaction between the chaotropic halides are reduced by glycerol addition, which is in line with a recent measurement of the solvent excess enthalpy for the same systems studied here. Moreover, our calculations indicate that the effect of an osmolyte (glycerol) on surface ion concentrations parallels the known effect of osmolytes on protein folding.

KW - glycerol

KW - Hofmeister series

KW - interface

KW - PMF

KW - polarization

UR - http://www.scopus.com/inward/record.url?scp=84883776406&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84883776406&partnerID=8YFLogxK

U2 - 10.1021/jz4014695

DO - 10.1021/jz4014695

M3 - Article

VL - 4

SP - 2885

EP - 2889

JO - Journal of Physical Chemistry Letters

JF - Journal of Physical Chemistry Letters

SN - 1948-7185

IS - 17

ER -