Related Experiment Video
Updated: Jun 12, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Narrowing of protein NMR spectral lines broadened by chemical exchange
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
Abstract:
Broadening of spectral lines is a signature of chemical exchange phenomena on microsecond to millisecond time scales but has deleterious effects on spectral resolution and sensitivity. A multipulse method based on chemical shift scaling that reduces chemical exchange broadening during frequency-encoding periods of liquid-state multidimensional NMR experiments is described. The proposed scheme utilizes low-power radiofrequency pulses, which offer the advantages of short cycle times and minimal sample heating. The method is suitable for biological macromolecules, as relaxation not resulting from chemical exchange is reduced by placing the magnetization along the z axis for part of the evolution trajectory. The resolution and sensitivity enhancement for resonances broadened by chemical exchange is demonstrated on the protein ribonuclease A. The work demonstrates the feasibility of applying coherent averaging techniques, which were originally developed in solid-state NMR spectroscopy, to biological NMR spectroscopy in the liquid state for resolution enhancement and facilitates the detection of resonances that are severely broadened by chemical exchange processes.
Related Concept Videos
¹H NMR: Interpreting Distorted and Overlapping Signals
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
NMR Spectrometers: Resolution and Error Correction
NMR Spectroscopy Of Amines
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
NMR Spectroscopy: Chemical Shift Overview
For instance, the proton...
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
