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Updated: May 23, 2026
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Complex formation in aqueous trimethylamine-N-oxide (TMAO) solutions
Johannes Hunger1, Klaas-Jan Tielrooij, Richard Buchner
1FOM Institute AMOLF , Science Park 104, 1098 XG Amsterdam, The Netherlands.
The Journal of Physical Chemistry. B
|March 31, 2012
Summary
Trimethylamine-N-oxide (TMAO) slows water rotation near its hydrophobic parts and forms long-lived complexes with water at hydrophilic sites. These interactions significantly alter water
Area of Science:
- Physical Chemistry
- Biophysical Chemistry
- Solution Chemistry
Background:
- Trimethylamine-N-oxide (TMAO) is an osmolyte found in biological systems.
- Understanding TMAO's interaction with water is crucial for explaining its biological roles.
Purpose of the Study:
- To investigate the dynamics and interactions of water molecules in aqueous TMAO solutions.
- To elucidate the structural and dynamic effects of TMAO on water at a molecular level.
Main Methods:
- Broadband dielectric spectroscopy
- Femtosecond mid-infrared spectroscopy
- Isotopic dilution (HDO)
Main Results:
- Slower rotational dynamics of water near TMAO's hydrophobic groups.
- Formation of stable TMAO·nH2O complexes (n=2, 3) with lifetimes >50 ps.
- Enhanced dipole correlations and red-shifted O-D stretching vibrations due to strong water-TMAO interactions.
Conclusions:
- TMAO significantly alters water dynamics and structure through specific interactions.
- Long-lived water-TMAO complexes play a key role in these observed effects.
- Efficient vibrational energy transfer occurs between water and TMAO molecules.
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