skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effect of calcium ions on the interactions between surfaces end-grafted with weak polyelectrolytes

Journal Article · · Journal of Chemical Physics
DOI:https://doi.org/10.1063/1.5029377· OSTI ID:1566650

We study the interactions between two planar surfaces end-tethered with poly(acrylic acid) polymers in electrolyte solutions containing calcium ions, using a molecular theory. We found that by adding divalent calcium ions to an aqueous solution of monovalent ions leads to a dramatic reduction in the size and range of effective interactions between the two polymer layers. This is caused by the formation of favorable calcium bridges, i.e., complexes of one calcium ion and two carboxylic acid monomers, that reduce the effective charge of the polymer layers and, at sufficient calcium ion concentrations, can cause the polymer layers to collapse. For calcium ion concentrations above approximately 1 mM, the repulsions between the opposing end-grafted surfaces disappear and attractions occur. These attractions are correlated with the occurrence of interlayer divalent calcium bridges and do not occur for poly(acrylic acid) layers in contact with reservoir solutions containing only monovalent ions. This result indicates the suitability of divalent calcium ions to control and change the interaction range and strength, which is a useful property that is desirable in the design of stimuli-responsive nanomaterials.

Research Organization:
Energy Frontier Research Centers (EFRC) (United States). Center for Bio-Inspired Energy Science (CBES); Northwestern Univ., Evanston, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
SC0000989
OSTI ID:
1566650
Alternate ID(s):
OSTI ID: 1460128
Journal Information:
Journal of Chemical Physics, Vol. 149, Issue 16; ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 16 works
Citation information provided by
Web of Science

References (54)

Self-Assembled Monolayers and Polymer Brushes in Biotechnology:  Current Applications and Future Perspectives journal September 2005
Behavior of Surface-Anchored Poly(acrylic acid) Brushes with Grafting Density Gradients on Solid Substrates: 1. Experiment journal November 2007
Effect of counterions on the swelling of spherical polyelectrolyte brushes journal February 2005
Born energy, acid-base equilibrium, structure and interactions of end-grafted weak polyelectrolyte layers journal January 2014
On the stability of nanoparticles coated with polyelectrolytes in high salinity solutions journal October 2014
Contraction and Coagulation of Spherical Polyelectrolyte Brushes in the Presence of Ag + , Mg 2+ , and Ca 2+ Cations journal September 2016
Spherical polyelectrolyte brushes in the presence of multivalent counterions: The effect of fluctuations and correlations as determined by molecular dynamics simulations journal March 2008
Interaction between grafted polymeric brushes: A molecular-dynamics study journal September 1989
Self-organization of multivalent counterions in polyelectrolyte brushes journal August 2008
Bioinspired Artificial Single Ion Pump journal July 2013
Spherical polyelectrolyte brushes journal October 2007
Competitive calcium ion binding to end-tethered weak polyelectrolytes journal January 2018
Lessons from nature: stimuli-responsive polymers and their biomedical applications journal July 2002
Reversible Adhesion with Polyelectrolyte Brushes Tailored via the Uptake and Release of Trivalent Lanthanum Ions journal April 2015
A Molecular Dynamics Study of Two Apposing Polyelectrolyte Brushes with Mono- and Multivalent Counterions journal October 2009
Stimuli responsive polymers for biomedical applications journal January 2005
Interaction of Poly(methacrylic acid) Brushes with Metal Ions:  Swelling Properties journal May 2005
Lubrication by charged polymers journal September 2003
Multivalent ions induce lateral structural inhomogeneities in polyelectrolyte brushes journal December 2017
Brushes of strong polyelectrolytes in mixed mono- and tri-valent ionic media at fixed total ionic strengths journal January 2013
Analysis of Complexation Equilibria of Polyacrylic Acid by a Donnan-Based Concept journal March 1997
Weak polyelectrolytes tethered to surfaces: Effect of geometry, acid–base equilibrium and electrical permittivity journal January 2006
Coil-Collapse and Coil-Aggregation due to the Interaction of Cu 2+ and Ca 2+ Ions with Anionic Polyacylate Chains in Dilute Solution journal March 2010
Optical tweezers to measure the interaction between poly(acrylic acid) brushes journal October 2008
Ligand−Receptor Interactions between Surfaces: The Role of Binary Polymer Spacers journal September 2008
Isothermal Titration Calorimetry of the Polyelectrolyte/Water Interaction and Binding of Ca 2+ :  Effects Determining the Quality of Polymeric Scale Inhibitors journal May 2004
The effect of multivalent counterions to the structure of highly dense polystyrene sulfonate brushes journal August 2016
Behavior of Surface-Anchored Poly(acrylic acid) Brushes with Grafting Density Gradients on Solid Substrates  2. Theory journal November 2007
Shearing and compression behavior of end-grafted polyelectrolyte brushes with mono- and trivalent counterions: a molecular dynamics simulation journal August 2010
Charged Polymeric Brushes: Structure and Scaling Relations journal June 1994
Calcium-Mediated Adhesion of Nanomaterials in Reservoir Fluids journal September 2017
Stability behavior of anionic spherical polyelectrolyte brushes in the presence of La(III) counterions journal July 2010
Emergent Properties of Dense DNA Phases toward Artificial Biosystems on a Surface journal May 2014
Interactions between Charged Surfaces and Functionalized Grafted Polymer Layers journal August 2006
Polyacrylic Acid Brushes:  Surface Pressure and Salt-Induced Swelling journal October 2000
Collapse of sodium polyacrylate chains in calcium salt solutions journal May 2001
Structure and Interactions of Aggrecans: Statistical Thermodynamic Approach journal November 2008
Comparing Solvophobic and Multivalent Induced Collapse in Polyelectrolyte Brushes journal January 2017
Structure and interaction of weakly charged polyelectrolyte brushes: Self-consistent field theory journal October 1997
On the Theory of Grafted Weak Polyacids journal May 1994
Collapse of Spherical Polyelectrolyte Brushes in the Presence of Multivalent Counterions journal October 2006
Bridging contributions to polyelectrolyte brush collapse in multivalent salt solutions journal November 2015
Ionic Effects in Collapse of Polyelectrolyte Brushes journal July 2008
Heterogeneous Morphology and Dynamics of Polyelectrolyte Brush Condensates in Trivalent Counterion Solution journal February 2017
Lateral Structure Formation in Polyelectrolyte Brushes Induced by Multivalent Ions journal January 2017
Poisson–Boltzmann Theory of pH-Sensitive (Annealing) Polyelectrolyte Brush journal September 2011
Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications journal June 2005
How and Why Nanoparticle’s Curvature Regulates the Apparent p K a of the Coating Ligands journal February 2011
Calcium Binding and Ionic Conduction in Single Conical Nanopores with Polyacid Chains: Model and Experiments journal September 2012
The interplay of nanointerface curvature and calcium binding in weak polyelectrolyte-coated nanoparticles journal January 2018
The binding of free calcium ions in aqueous solution using chelating agents, phosphates and poly(acrylic acid) journal March 1983
Interaction of calcium ions and polyelectrolytes journal January 1996
Responsive Polymers End-Tethered in Solid-State Nanochannels: When Nanoconfinement Really Matters journal September 2010
Stimuli Responsive Polymers for Biomedical Applications journal June 2005

Cited By (3)