Related Experiment Video
Updated: Jul 14, 2026
14:44
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Methods for peak assignment in low-resolution multidimensional NMR cross-correlation relaxometry
N Marigheto1, L Venturi, D Hibberd
1Institute of Food Research, Norwich Research Park, Colney, Norwich, UK.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|June 26, 2007
Summary
New nuclear magnetic resonance (NMR) protocols simplify complex T1-T2 spectra assignment. These methods, including advanced cross-correlation techniques, offer broad applicability for analyzing molecular dynamics and structure.
Area of Science:
- Analytical Chemistry
- Biophysical Chemistry
- Spectroscopy
Background:
- Nuclear Magnetic Resonance (NMR) spectroscopy is crucial for characterizing molecular structure and dynamics.
- Assigning peaks in complex T1-T2 spectra can be challenging, limiting detailed analysis.
- Advanced NMR techniques are needed to overcome spectral complexity.
Purpose of the Study:
- To present novel NMR protocols for improved peak assignment in T1-T2 spectra.
- To explore the impact of varying spectrometer frequency and Carr-Purcell-Meiboom-Gill (CPMG) pulsing rates.
- To investigate the utility of 3D cross-correlation methods for spectral assignment.
Main Methods:
- Development and application of several NMR protocols for T1-T2 spectra.
- Systematic variation of spectrometer frequency and CPMG pulsing parameters.
- Implementation of chemical-shift, diffusion-weighted, and field-cycled T1-T2 cross-correlation methods.
Main Results:
- Demonstrated effective peak assignment in complex T1-T2 spectra using the developed protocols.
- Showcased the influence of spectrometer frequency and CPMG rate on spectral resolution and assignment.
- Validated the utility of 3D cross-correlation NMR for enhancing spectral assignment.
Conclusions:
- The presented NMR protocols provide powerful tools for assigning peaks in complex T1-T2 spectra.
- The methodology is applicable to various systems, exemplified by aqueous sucrose solutions.
- These techniques advance the capability for detailed molecular analysis using NMR.
More Related Videos
Related Concept Videos
01:182D NMR: Overview of Heteronuclear Correlation Techniques
Heteronuclear correlation spectroscopy is an analytical technique that investigates the coupling between different types of nuclei, often a proton and an X-nucleus, such as carbon-13 or nitrogen-15. This method is commonly used in nuclear magnetic resonance (NMR) spectroscopy to gain insights into complex chemical compounds' structural and compositional aspects. A typical heteronuclear correlation spectrum displays X-nucleus chemical shifts on one axis and a proton spectrum on the other axis.
01:162D NMR: Overview of Homonuclear Correlation Techniques
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
COSY90 is the standard two-dimensional (2D) COSY experiment that...
01:192D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
Heteronuclear single-quantum correlation spectroscopy (HSQC) is a 2D NMR technique that reveals one-bond correlations between hydrogen and a heteronucleus. The HSQC experiment is similar to the heteronuclear correlation experiment (HETCOR) but is more sensitive. In the HSQC spectrum, the proton chemical shift is plotted on the horizontal F2 axis, while the 13C chemical shift is plotted on the vertical F1 axis. The corresponding proton and 13C spectra are also shown. The HSQC contour plot does...
01:14NMR Spectrometers: Resolution and Error Correction
When magnetic nuclei in a sample achieve resonance and undergo relaxation, the signal detected in NMR is an approximately exponential free induction decay. Fourier transform of an exponential decay yields a Lorentzian peak in the frequency domain. Lorentzian peaks in an NMR spectrum are defined by their amplitude, full width at half maximum, and position, where the peak width is governed by the spin-spin relaxation time alone. In real experiments, however, the applied magnetic field is rendered...
01:062D NMR: Homonuclear Correlation Spectroscopy (COSY)
Homonuclear correlation spectroscopy, or COSY, is a 2-dimensional NMR technique that provides information about coupled protons. Typically, the geminal and vicinal coupling are observed. For example, consider the COSY spectrum of ethyl acetate, where its 1D proton NMR spectrum is plotted along the vertical and horizontal axes with their corresponding chemical shift scale. Three spots on the diagonal corresponding to the three peaks in the 1D proton spectrum are called diagonal peaks. The COSY...
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
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...
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...