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Hydrogen-exchange kinetics studied through analysis of self-decoupling of nuclear magnetic resonance.

ABSTRACT: Hydrogen exchange between solute and water molecules occurs across a wide range of timescales. Rapid hydrogen-exchange processes can effectively diminish ¹H-¹⁵N scalar couplings. We demonstrate that the self-decoupling of ¹⁵N nuclear magnetic resonance can allow quantitative investigations of hydrogen exchange on a micro- to millisecond timescale, which is relatively difficult to analyze with other methods. Using a Liouvillian matrix incorporating hydrogen exchange as a mechanism for scalar relaxation, the hydrogen exchange rate can be determined from ¹⁵N NMR line shapes recorded with and without ¹H decoupling. Self-decoupling offers a simple approach to analyze the kinetics of hydrogen exchange in a wide range of timescale.

SUBMITTER: Nepravishta R

PROVIDER: S-EPMC7067644 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Hydrogen-exchange kinetics studied through analysis of self-decoupling of nuclear magnetic resonance.

Nepravishta Ridvan R Yu Binhan B Iwahara Junji J

Journal of magnetic resonance (San Diego, Calif. : 1997) 20200116

Hydrogen exchange between solute and water molecules occurs across a wide range of timescales. Rapid hydrogen-exchange processes can effectively diminish 1H-15N scalar couplings. We demonstrate that the self-decoupling of 15N nuclear magnetic resonance can allow quantitative investigations of hydrogen exchange on a micro- to millisecond timescale, which is relatively difficult to analyze with other methods. Using a Liouvillian matrix incorporating hydrogen exchan ...[more]

PMID: 31982802

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Hydrogen-exchange kinetics studied through analysis of self-decoupling of nuclear magnetic resonance.

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Hydrogen-exchange kinetics studied through analysis of self-decoupling of nuclear magnetic resonance.

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