Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

NMR Spectrometers: Resolution and Error Correction01:14

NMR 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...
Two-Dimensional (2D) NMR: Overview01:12

Two-Dimensional (2D) NMR: Overview

The 1D NMR spectrum of large and complex molecules like natural products has complicated splitting patterns and overlapping signals, which can be easily interpreted using 2-dimensional (2D) NMR. Unlike 1D NMR, 2D NMR has two frequency axes that provide the coupling information between the nucleus A and nucleus B in a molecule. The process from which 2D spectra are obtained has four steps.
The first step is the preparation period, during which nucleus A is excited with a radiofrequency pulse.
Double Resonance Techniques: Overview01:12

Double Resonance Techniques: Overview

Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
2D NMR: Overview of Homonuclear Correlation Techniques01:16

2D 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...
2D NMR: Overview of Heteronuclear Correlation Techniques01:18

2D 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.
¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H 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...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Preparing future dentists for artificial intelligence: a cross-sectional study of perceptions and educational needs in China.

Frontiers in public health·2026
Same author

Risk factors and preliminary prediction models for trauma-induced coagulopathy and 28-day mortality in severely injured patients: a retrospective observational cohort study.

Frontiers in medicine·2026
Same author

Procedural Rigor and Reproducibility in NMR Metabolomics: Community Practices and Challenges.

Critical reviews in analytical chemistry·2026
Same author

Nanoscale Dielectric Gene Dual-Regulations in High-Entropy Materials for Enhanced Electromagnetic Wave Absorption Over Low-Mid Frequency.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

Three-Dimensional High-Efficiency Superlithiophilic Interface Toward Air-Stable Garnet-Based All-Solid-State Lithium Metal Batteries.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

Decoherence Principles and Algorithms for One-Dimensional Nonuniform Sampling Schedules for Multidimensional NMR.

Analytical chemistry·2025

Related Experiment Video

Updated: May 31, 2026

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins
09:25

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins

Published on: November 1, 2024

Sensitivity enhancement for maximally resolved two-dimensional NMR by nonuniform sampling.

David Rovnyak1, Mark Sarcone, Ze Jiang

  • 1Department of Chemistry, Bucknell University, Lewisburg, PA 17837, USA. drovnyak@bucknell.edu.

Magnetic Resonance in Chemistry : MRC
|July 14, 2011
PubMed
Summary

Non-uniform sampling (NUS) enhances signal-to-noise ratio (SNR) in Nuclear Magnetic Resonance (NMR) experiments. This method allows for high-resolution spectra acquisition in shorter times, particularly beneficial for dilute samples like bile salts.

Keywords:
HMQCNMRbile acidmaximum entropy reconstructionnonuniform sampling

More Related Videos

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements
08:54

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements

Published on: May 1, 2017

Related Experiment Videos

Last Updated: May 31, 2026

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins
09:25

NMR 15N Relaxation Experiments for the Investigation of Picosecond to Nanoseconds Structural Dynamics of Proteins

Published on: November 1, 2024

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements
08:54

NMR Spectroscopy as a Robust Tool for the Rapid Evaluation of the Lipid Profile of Fish Oil Supplements

Published on: May 1, 2017

Area of Science:

  • Nuclear Magnetic Resonance (NMR) spectroscopy
  • Analytical Chemistry
  • Biophysical Chemistry

Background:

  • Achieving high resolution in NMR requires long acquisition times to capture the free induction decay (FID) up to tmax = πT2.
  • Acquiring data beyond approximately 1.26 T2 adds more noise than signal, necessitating a trade-off between resolution and signal-to-noise ratio (SNR).

Purpose of the Study:

  • To develop and validate an analytic theory for signal-to-noise ratio (SNR) enhancement using non-uniform sampling (NUS).
  • To demonstrate the practical application of NUS for acquiring high-resolution NMR spectra of challenging samples.

Main Methods:

  • Derivation of analytic theory for intrinsic SNR enhancement in NUS compared to uniform sampling for equivalent experimental times.
  • Validation of the theory using simulations across various tmax and exponential weighting schemes.
  • Application of NUS for acquiring Heteronuclear Multiple Quantum Coherence (HMQC) spectra.

Main Results:

  • Analytic theory predicts and simulations confirm SNR enhancements in the time domain, often twofold, for NUS when tmax is around πT2.
  • These SNR enhancements are directly reflected in the reconstructed spectra, particularly with maximum entropy methods.
  • NUS enabled the acquisition of high-resolution HMQC spectra for dilute bile salt samples, crucial for resolving signals in the indirect carbon dimension.

Conclusions:

  • Non-uniform sampling (NUS) offers a significant SNR enhancement in NMR spectroscopy compared to traditional uniform sampling.
  • NUS allows for the acquisition of high-resolution spectra within shorter experimental times, overcoming limitations imposed by transverse relaxation (T2).
  • This technique is particularly valuable for analyzing dilute or complex biological molecules where spectral resolution and sensitivity are critical.