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

Electrospray Ionization (ESI) Mass Spectrometry01:12

Electrospray Ionization (ESI) Mass Spectrometry

2.4K
Higher molecular weight biomolecules are nonvolatile compounds that may decompose before ionizing or vaporizing during mass analysis with conventional electron impact ionization methods. Accordingly, electrospray ionization (ESI) is the favored method for vaporizing and ionizing biomolecules as it circumvents rapid fragmentation and enables the recording of mass signals for the entire biomolecule.
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
2.4K
Ionization Energy03:12

Ionization Energy

43.5K
The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy (IE1). The first ionization energy for an element, X, is the energy required to form a cation with 1+ charge:
43.5K
Gas Chromatography: Types of Columns and Stationary Phases01:17

Gas Chromatography: Types of Columns and Stationary Phases

2.4K
Gas chromatography (GC) relies on stationary phases to separate and analyze components in a sample. There are two main types of stationary phases: liquid and solid. Liquid stationary phases are non-volatile, thermally stable, and chemically inert liquids coated onto the column. Solid stationary phases are particles of adsorbent material, such as silica gel or molecular sieves.
For an analyte to remain on the column for a sufficient amount of time, it must exhibit some level of compatibility (or...
2.4K
Energy Basics02:27

Energy Basics

47.8K
Chemical reactions, such as those that occur when you light a match, involve changes in energy as well as matter.
47.8K
Phase Diagrams02:39

Phase Diagrams

50.3K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
50.3K
Phase Transitions02:31

Phase Transitions

23.3K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
23.3K

You might also read

Related Articles

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

Sort by
Same author

hexABC seeking the physical code of DNA.

Nature communications·2026
Same author

Decoding Cancer-Associated Mutations in DNA Polymerase η through Atomistic Simulations.

Journal of chemical theory and computation·2026
Same author

Structural and functional role of the magnesium ion in the human oxytocin receptor.

Journal of inorganic biochemistry·2026
Same author

pH-dependent structural dynamics of neuropeptide Y in aqueous solution.

PloS one·2026
Same author

Protonation-dependent substrate release in a bacterial homolog of vesicular glutamate.

Biophysical journal·2026
Same author

MiMiCPy-FM: A User-Friendly Force Matching Tool for Extending the Time Scale of QM/MM MD MiMiC Simulations.

Journal of chemical information and modeling·2026

Related Experiment Video

Updated: Feb 9, 2026

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
05:47

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry

Published on: February 19, 2020

10.0K

A computational model for protein ionization by electrospray based on gas-phase basicity.

Roberto Marchese1, Rita Grandori, Paolo Carloni

  • 1SISSA and INFM-DEMOCRITOS Center, Trieste, Italy.

Journal of the American Society for Mass Spectrometry
|September 21, 2012
PubMed
Summary

Apparent gas-phase basicity explains protein charge in electrospray ionization mass spectrometry. This finding unifies principles for folded and unfolded proteins, aiding data interpretation.

More Related Videos

Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
09:18

Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics

Published on: April 17, 2017

10.3K
Determination of the Gas-phase Acidities of Oligopeptides
11:00

Determination of the Gas-phase Acidities of Oligopeptides

Published on: June 24, 2013

11.6K

Related Experiment Videos

Last Updated: Feb 9, 2026

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
05:47

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry

Published on: February 19, 2020

10.0K
Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
09:18

Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics

Published on: April 17, 2017

10.3K
Determination of the Gas-phase Acidities of Oligopeptides
11:00

Determination of the Gas-phase Acidities of Oligopeptides

Published on: June 24, 2013

11.6K

Area of Science:

  • Biochemistry
  • Analytical Chemistry
  • Computational Chemistry

Background:

  • Interpreting electrospray ionization mass spectrometry (ESI-MS) data requires understanding protein charge.
  • Existing hypotheses for protein charge in ESI-MS differ for folded and unfolded proteins.

Purpose of the Study:

  • To identify the key factor governing protein charge in ESI-MS.
  • To develop a unified model for protein ionization applicable to both folded and unfolded proteins.

Main Methods:

  • Investigated gas-phase structure and energetics of proteins using hybrid Monte Carlo/molecular dynamics.
  • Explored conformer and protomer space, including zwitterionic states.
  • Developed a parameter-free model for protein potential energy functions.

Main Results:

  • Apparent gas-phase basicity of desolvated protein ions is the unifying factor for electrospray ionization.
  • The developed model accurately predicts experimental charge for folded proteins.
  • The model confirms the correlation between protein charge and the square root of protein mass.

Conclusions:

  • Gas-phase basicity is the critical determinant of protein charge in ESI-MS.
  • A single, general model can explain protein ionization across different protein types.
  • This work provides a foundation for more accurate ESI-MS data interpretation.