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Updated: Sep 30, 2026

Using Solution NMR to Characterize Biomolecular Condensates Under Biphasic Conditions
Published on: April 17, 2026
[Effect of common ions in water on water association by 17O-NMR]
Ruihua Li1, Zhanpeng Jiang, Shaoqi Shi
1Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
Abstract:
There are various kinds of trace ions in water supply, such as Na+, K+, Ca2+, Mg2+ and Cl-, SO(4)2-, CO(3)2- etc. 17O-NMR chemical shift and line-width of water were measured under different temperature and different concentrations of various salts in aqueous solutions containing those ions. The relationship of 17O-NMR chemical shift and line-width of water to water association and the effect of ions on water association were analyzed. Cations promoted water association and anions destroyed water association. Generally, the more the ionic charge and the larger the ionic radius, the larger was the effect of those ions on water association. Besides, the effect of ionic charge on water association was more significant than that of ionic radius.
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