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

IR Frequency Region: Fingerprint Region01:03

IR Frequency Region: Fingerprint Region

1.0K
IR spectra are divided into two main regions: the diagnostic region and the fingerprint region. The diagnostic region of the spectrum lies above 1500 cm−1. The absorptions resulting from single-bond vibrations of the N–H, C–H, and O–H stretch at higher wavenumbers and appear on the left side of the spectrum. The stretching absorptions of the C≡C and C≡N occur between 2100–2300 cm−1. In contrast, those arising from stretching absorptions of the...
1.0K
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)01:19

2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)

851
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...
851
NMR Spectroscopy of Aromatic Compounds01:14

NMR Spectroscopy of Aromatic Compounds

4.9K
Aromatic compounds can be identified or analyzed using proton NMR and carbon‐13 NMR. Typically, aromatic hydrogens or hydrogens directly bonded to the aromatic rings are strongly deshielded by the aromatic ring current. Therefore, they absorb in the range of 6.5–8.0 ppm in proton NMR spectra. For instance, aromatic hydrogens directly bonded to the benzene ring absorb at 7.3 ppm. However, aromatic hydrogens of larger rings absorb farther upfield or downfield than the ideal range.
4.9K
Spectroscopy of Carboxylic Acid Derivatives01:26

Spectroscopy of Carboxylic Acid Derivatives

2.5K
Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and...
2.5K
¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

1.1K
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...
1.1K
NMR Spectroscopy: Chemical Shift Overview01:15

NMR Spectroscopy: Chemical Shift Overview

1.6K
The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...
1.6K

You might also read

Related Articles

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

Sort by
Same author

Graphical exploration of 600- and 60-MHz proton NMR spectral datasets from ground roast coffee extracts.

Magnetic resonance in chemistry : MRC·2023
Same author

3,4-Methylenedioxymethamphetamine quantification via benchtop <sup>1</sup>H qNMR spectroscopy: Method validation and its application to ecstasy tablets collected at music festivals.

Journal of pharmaceutical and biomedical analysis·2022
Same author

Comparative study of the analysis of seized samples by GC-MS, <sup>1</sup>H NMR and FT-IR spectroscopy within a Night-Time Economy (NTE) setting.

Journal of pharmaceutical and biomedical analysis·2022
Same author

Mitigating instrument effects in 60 MHz <sup>1</sup>H NMR spectroscopy for authenticity screening of edible oils.

Food chemistry·2021
Same author

Detection, discrimination and quantification of amphetamine, cathinone and nor-ephedrine regioisomers using benchtop <sup>1</sup> H and <sup>19</sup> F nuclear magnetic resonance spectroscopy.

Magnetic resonance in chemistry : MRC·2021
Same author

High-throughput screening of argan oil composition and authenticity using benchtop <sup>1</sup> H NMR.

Magnetic resonance in chemistry : MRC·2020

Related Experiment Video

Updated: Aug 24, 2025

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics
13:16

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics

Published on: July 31, 2021

2.0K

Authentication of saffron using 60 MHz 1H NMR spectroscopy.

Yvonne Gunning1, Kate S Davies1, E Kate Kemsley1

  • 1Core Science Resources Group, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK.

Food Chemistry
|October 26, 2022
PubMed
Summary

Nuclear Magnetic Resonance (NMR) spectroscopy identified adulterated saffron spice. Analysis of online saffron samples revealed 7 out of 33 contained undisclosed foreign matter, impacting spice authenticity.

Keywords:
AdulterationAnomalyAuthenticityBenchtopNMROutlierSaffronSpectroscopy

More Related Videos

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.5K
Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional &#960;-conjugate Systems
09:57

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems

Published on: February 10, 2020

7.2K

Related Experiment Videos

Last Updated: Aug 24, 2025

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics
13:16

Pure Shift Nuclear Magnetic Resonance: a New Tool for Plant Metabolomics

Published on: July 31, 2021

2.0K
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.5K
Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional &#960;-conjugate Systems
09:57

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems

Published on: February 10, 2020

7.2K

Area of Science:

  • Analytical Chemistry
  • Food Science
  • Spectroscopy

Background:

  • Saffron spice authenticity is crucial for culinary and medicinal applications.
  • Adulteration of saffron with foreign matter is a significant economic and quality concern.
  • Nuclear Magnetic Resonance (NMR) spectroscopy offers a powerful tool for chemical profiling and authentication.

Purpose of the Study:

  • To develop and apply NMR-based methods for detecting adulterants in saffron spice.
  • To assess the authenticity of saffron samples sourced from online marketplaces.
  • To identify characteristic metabolites and potential adulterants in saffron extracts.

Main Methods:

  • Proton NMR spectroscopy (60 MHz) was used to analyze saffron extracts and potential adulterants.
  • One-class classification models (SIMCA, nearest neighbor, isolation forest) were trained using spectra from trusted saffron samples.
  • Machine learning models were applied to analyze spectra of saffron samples from online vendors.
  • Confirmatory spectral analysis was performed using 600 MHz NMR.

Main Results:

  • High-quality NMR spectra were obtained, revealing characteristic saffron metabolites (picrocrocin, crocins, kaempferol) and fatty acids.
  • Analysis of 33 online saffron samples identified 7 as highly anomalous based on spectral data.
  • Comparison with known mixtures and advanced NMR analysis suggested the presence of significant undisclosed foreign matter in anomalous samples.

Conclusions:

  • NMR spectroscopy, coupled with chemometrics, is effective for detecting adulteration in saffron spice.
  • A notable proportion of saffron samples from online markets may be adulterated with foreign substances.
  • This study highlights the need for robust analytical methods to ensure saffron quality and authenticity.