Related Experiment Video
Updated: Jun 1, 2026
16:11
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Molecular dynamics simulation study of ion interactions with zwitterions
Qing Shao1, Yi He, Shaoyi Jiang
1Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States.
The Journal of Physical Chemistry. B
|June 2, 2011
Summary
Molecular dynamics simulations reveal distinct cation preferences for carboxybetaine (CB) and sulfobetaine (SB) zwitterions. While both associate more strongly with Li(+) and Na(+), sulfobetaine preferentially binds K(+) and Cs(+).
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Zwitterions like carboxybetaine (CB) and sulfobetaine (SB) are crucial in various chemical and biological applications.
- Understanding their interactions with cations is essential for optimizing their performance in solution.
Purpose of the Study:
- To investigate the association patterns between CB and SB with alkali metal cations (Li+, Na+, K+, Cs+) in aqueous solutions.
- To elucidate the influence of cation type and anion identity on zwitterion-cation complexation.
Main Methods:
- Molecular dynamics (MD) simulations were employed to study zwitterion-cation associations.
- Analysis included the number and lifetime of associations under varying conditions, including competitive binding scenarios.
Main Results:
- Both zwitterions exhibited the same cation association order: Li+ > Na+ > K+ > Cs+.
- Significant differences in association variation were observed between CB and SB as a function of cation type.
- Anion type (Cl-, Br-, F-) had a notable effect on the observed association trends.
- Competitive simulations confirmed that CB associates more strongly with Li+ and Na+, while SB shows preferential binding to K+ and Cs+.
Conclusions:
- Zwitterion-cation association strength is highly dependent on the specific cation and zwitterion involved.
- The findings provide critical insights into the selective binding capabilities of zwitterions, relevant for designing advanced materials and chemical processes.
More Related Videos
08:54Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
Published on: January 25, 2020
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
Related Concept Videos
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
01:28Ionic Association
The ionic association is the association of oppositely charged ions in an electrolyte solution to form ion pairs. Bjerrum defined ion pairs as two oppositely charged ions whose electrostatic attraction exceeds the thermal energy of the system, typically expressed as 2kT. Electrostatic attraction depends on ionic charge, separation distance, and the dielectric constant of the medium. Thermal energy, represented by kT, reflects the tendency of ions to move independently due to molecular motion.
01:23Theory of Strong Electrolytes
The interionic forces of the strong electrolytes depend on the solvent's dielectric constant, which is the ability of a solvent to store electrical energy, based on its polarizability. and the solution's concentration. In high-dielectric solvents and in dilute solutions, weak electrostatic forces keep ions apart. However, in low-dielectric solvents or concentrated solutions, stronger interionic forces may cause ions to pair up as ionic doublets despite being fully ionized. The theory of strong...
01:24Van der Waals Interactions
Atoms and molecules interact with each other through intermolecular forces. These electrostatic forces arise from attractive or repulsive interactions between particles with permanent, partial, or temporary charges. The intermolecular forces between neutral atoms and molecules are ion–dipole, dipole–dipole, and dispersion forces, collectively known as van der Waals forces.Polar molecules have a partial positive charge on one end and a partial negative charge on the other end of the molecule,...
03:45Formation of Complex Ions
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
01:17Ion Exchange
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or basic...