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

Mass Spectrometry of Amines01:15

Mass Spectrometry of Amines

5.3K
In mass spectroscopy, amines undergo fragmentation to give parent ions with odd molecule weights. This observed mass spectrum follows the nitrogen rule; a molecule with an odd number of nitrogen atoms produces a molecular ion with an odd molecular weight. Amines undergo fragmentation through α cleavage, producing nitrogen-containing cations—iminium ions—and alkyl radicals. Mass spectra of aromatic and cyclic aliphatic amines exhibit strong molecular ion peaks, but acyclic...
5.3K
NMR Spectroscopy Of Amines01:19

NMR Spectroscopy Of Amines

10.8K
In proton NMR spectroscopy, primary amines and secondary amines showcase their N–H protons as a broad signal in the chemical shift range between δ 0.5 and 5 ppm. The exact position in this range depends on several factors, including sample concentration, hydrogen bonding, and the type of solvent used. Since amine protons undergo fast proton exchange in solution, the protons are labile and therefore do not participate in any splitting with adjacent protons. Thus, the observed peak is...
10.8K
Basicity of Aliphatic Amines01:21

Basicity of Aliphatic Amines

6.7K
Amines can behave as Brønsted–Lowry bases by accepting a proton from the acid to form corresponding conjugate acids. Due to a lone pair of nonbonding electrons, aliphatic amines can also act as Lewis bases by forming a covalent bond with an electrophile.
To measure the basicity of amines, two conventions are generally used. The first defines Kb as the basicity constant for the deprotonation reaction of water by the amine, as presented in Figure 1. Conventionally, lower Kb indicates higher...
6.7K
Amino acids03:42

Amino acids

103.8K
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
103.8K
Mass Spectrometry: Amine Fragmentation00:55

Mass Spectrometry: Amine Fragmentation

2.2K
Amines can be identified using mass spectroscopy based on their characteristic fragmentation patterns. The molecular ions of amines undergo fragmentation via ⍺-cleavage. The ⍺-cleavage of the carbon-carbon bonds in amines generates an alkyl radical and resonance-stabilized nitrogen-containing cation.
In amines, the number of nitrogen atoms affects the mass of the molecular ion, which is described by the nitrogen rule of mass spectrometry. This rule states that a compound containing a single...
2.2K
NMR and Mass Spectroscopy of Carboxylic Acids01:30

NMR and Mass Spectroscopy of Carboxylic Acids

5.2K
In ¹H NMR spectroscopy, acidic protons (–COOH) of carboxylic acids are highly deshielded and absorb far downfield, at around 9–12 ppm. The chemical shift value depends on the concentration and solvent used.
While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
Carboxylic acids are easily identified by dissolving them in deuterium oxide, which results in a rapid exchange of the acidic protons with deuterium. This leads to the...
5.2K

You might also read

Related Articles

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

Sort by
Same author

Simulating closed- and open-quantum photoinduced electron dynamics for time-resolved NEXAFS.

The Journal of chemical physics·2026
Same author

A computational approach for the calculation of two-dimensional infrared spectra: Application to the amide I band.

The Journal of chemical physics·2026
Same author

Quantitative assessment of flow between cerebrospinal and interstitial fluid compartments in humans.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

<i>In-operando</i> dipole orientation for bipolar injection from air-stable electrodes into organic semiconductors.

Materials horizons·2026
Same author

Time-Dependent Open-Quantum Approach to Two-Dimensional Electronic Spectroscopy within a GW/BSE Active Space.

Journal of chemical theory and computation·2026
Same author

Mechanism of polypeptide translocation through gold nanopores in view of sequencing applications.

Nanoscale·2026

Related Experiment Video

Updated: Jan 12, 2026

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

6.0K

Role of Ions in Solvated Amino Acids Raman Spectra.

Giulia Dall'Osto1, Ornella Vaccarelli2, Dmitry Malyshev3

  • 1Department of Pharmaceutical and Chemical Sciences, University of Trieste, via L. Giorgieri 1, Trieste 34127, Italy.

The Journal of Physical Chemistry. B
|November 8, 2025
PubMed
Summary

Metal ions significantly alter Raman spectra of amino acids and peptide models. This study provides crucial data for interpreting the Raman spectra of proteins and biological materials in ionic solutions.

More Related Videos

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
10:03

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Published on: June 27, 2014

18.3K
Workflow Based on the Combination of Isotopic Tracer Experiments to Investigate Microbial Metabolism of Multiple Nutrient Sources
12:47

Workflow Based on the Combination of Isotopic Tracer Experiments to Investigate Microbial Metabolism of Multiple Nutrient Sources

Published on: January 22, 2018

9.9K

Related Experiment Videos

Last Updated: Jan 12, 2026

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

6.0K
Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
10:03

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy

Published on: June 27, 2014

18.3K
Workflow Based on the Combination of Isotopic Tracer Experiments to Investigate Microbial Metabolism of Multiple Nutrient Sources
12:47

Workflow Based on the Combination of Isotopic Tracer Experiments to Investigate Microbial Metabolism of Multiple Nutrient Sources

Published on: January 22, 2018

9.9K

Area of Science:

  • * Molecular Spectroscopy
  • * Computational Chemistry
  • * Biochemistry

Background:

  • * Raman spectroscopy analyzes molecular chemical bonds, particularly in peptides.
  • * Proteins and peptides are typically studied in solutions containing ions for stability.
  • * The effect of ions on amino acid and peptide Raman spectra is not well understood.

Purpose of the Study:

  • * To investigate the impact of various metal ions on the Raman spectra of key amino acids and a peptide model.
  • * To analyze spectral shifts and intensity variations caused by different cations.
  • * To provide a reference for interpreting protein and biological material spectra in ionic environments.

Main Methods:

  • * Density functional theory (DFT) simulations were employed.
  • * Raman spectroscopy was used for experimental validation.
  • * The study focused on four amino acids (glutamate, tyrosine, cysteine, serine) and N-methylacetamide.

Main Results:

  • * Metal ions were observed to associate with oxygen atoms in the amino acids.
  • * Copper(II) ions (Cu2+) were found to promote Raman resonance.
  • * Characteristic Raman peaks of amino acids showed distinct shifts in the presence of different metal ions.

Conclusions:

  • * Metal ions influence the Raman spectra of amino acids and peptide models.
  • * The findings offer valuable insights into spectral interpretation for biological molecules in ionic solutions.
  • * This research establishes a foundation for understanding ion-protein interactions via Raman spectroscopy.