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Chemical exchange induced Hahn echo modulation in pulsed electron paramagnetic resonance experiment.

ABSTRACT: Triarylmethyl (TAM) radicals are probes well suited to study microenvironment parameters using pulse electron paramagnetic resonance (EPR) due to their long relaxation times. Here, we are reporting the study of relaxation properties of monophosphonated TAM radicals in the presence of chemical exchange processes. The dependence of Hahn and inversion recovery echo on the solution pH and the chemical exchange rate are discussed. The modulation of Hahn echo intensity in solutions due to chemical exchange is observed in pulse EPR experiments. An analysis of the Hahn echo intensity decay allows for the quantitative determination of the chemical exchange rate and solution pH value.

SUBMITTER: Bobko AA

PROVIDER: S-EPMC7282351 | biostudies-literature |

REPOSITORIES: biostudies-literature

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