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Enhancing the sensitivity of multidimensional NMR experiments by using triply-compensated ? pulses.

ABSTRACT: In multidimensional solution NMR experiments, ? pulses are used extensively for inversion and refocusing operations on 1H, 13C and 15N nuclei. Pulse miscalibration, off-resonance effects, and J-coupling evolution during ? pulse execution result in severe signal losses that are exacerbated at high magnetic fields. Here, we report the implementation of a triply-compensated ? pulse (G5) optimized for both inversion and refocusing in widely used 2- and 3-dimensional experiments. By replacing most of the hard ? pulses, adiabatic or composite pulses on the 1H, 13C and 15N channels with G5 pulses, we obtained signal enhancements ranging from 80 to 240%. We anticipate that triply-compensated pulses will be crucial for improving the performance of multidimensional and multinuclear pulse sequences at ultra-high fields.

SUBMITTER: Xia Y

PROVIDER: S-EPMC5738291 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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