Correcting for magnetic field drift in magic-angle spinning NMR datasets

Eszter E Najbauer; Loren B Andreas

doi:10.1016/j.jmr.2019.05.005

Correcting for magnetic field drift in magic-angle spinning NMR datasets

J Magn Reson. 2019 Aug:305:1-4. doi: 10.1016/j.jmr.2019.05.005. Epub 2019 May 16.

Authors

Eszter E Najbauer¹, Loren B Andreas²

Affiliations

¹ Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, D-37077 Göttingen, Germany.
² Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, D-37077 Göttingen, Germany. Electronic address: land@nmr.mpibpc.mpg.de.

PMID: 31158790
DOI: 10.1016/j.jmr.2019.05.005

Abstract

Magnetic field drift during magic angle spinning (MAS) NMR measurements is detrimental to the spectra, causing broadening of lines and distortion of lineshapes, especially in high-quality samples with linewidths of less than 0.1 ppm. We report that a simple linear correction for magnet drift can be used to improve the quality of proton detected MAS NMR measurements. Despite the fact that the magnetic field of superconducting magnets changes in a non-linear fashion, we find that when data acquisition is sufficiently short, a linear correction is a good approximation to the actual field drift. We used a script written in the C programming language for linear drift correction of multidimensional datasets (2D, 3D, 4D), which can be executed directly from Bruker Topspin. A second script allows datasets to be subdivided into arbitrarily short measurements, individually corrected, and concatenated before processing.

Keywords: Magic-angle spinning; Magnetic field drift; Membrane protein; Proton detection.