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

2.6K
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...
2.6K
Chemical Ionization (CI) Mass Spectrometry01:21

Chemical Ionization (CI) Mass Spectrometry

1.6K
The molecular ion peak of a molecule in the mass spectrum provides vital information for molecular identification. However, conventional electron impact ionization can lead to the rapid dissociation of some molecular ions before they reach the detector. A milder ionization method is required to increase the lifetime of such ionized analyte molecules. Chemical ionization (CI) is a gas-phase protonation reaction useful for mass-analyzing analyte molecules that are easily protonated to yield the...
1.6K
Ion-Exchange Chromatography01:09

Ion-Exchange Chromatography

2.5K
Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
2.5K
Capillary Electrophoresis: Instrumentation01:20

Capillary Electrophoresis: Instrumentation

1.4K
Capillary electrophoresis instrumentation typically consists of several key components. A high-voltage power supply generates the electric field necessary for the separation by connecting to an anode (the positively charged electrode) and a cathode (the negatively charged electrode) located in buffer reservoirs at each end of the capillary tube. The system includes a sample vial, a fused silica capillary tube coated with polyimide for mechanical strength through which the sample components...
1.4K
Capillary Electrophoresis: Applications01:30

Capillary Electrophoresis: Applications

1.6K
Capillary electrophoretic separations offer various modes, each with unique applications. These modes include capillary zone electrophoresis, capillary gel electrophoresis, capillary array electrophoresis, capillary isoelectric focusing, capillary isotachophoresis, micellar electrokinetic chromatography, and capillary electrochromatography.
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...
1.6K
Electrophoresis: Overview01:20

Electrophoresis: Overview

4.5K
Electrophoresis is a powerful analytical separation technique that relies on the differential migration of charged species when subjected to an electric field. The core strength of electrophoresis lies in its ability to separate high-molecular-weight species in complex mixtures. It has found widespread use in biochemistry, molecular biology, and analytical chemistry, allowing the separation of compounds like amino acids, nucleotides, carbohydrates, and proteins with excellent resolution.
There...
4.5K

You might also read

Related Articles

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

Sort by
Same author

Valorization of birch tops and branches containing mechanically inseparable wood and bark.

Green chemistry : an international journal and green chemistry resource : GC·2026
Same author

In-Depth Analysis of the Data from an Interlaboratory Study of Quantitative Non-Target Screening-How Do the Instrumental Methods Compare?

Molecules (Basel, Switzerland)·2026
Same author

Molecular networking, conformal predictions and revised fingerprint-based models for discovering endocrine disruptors in mixtures.

Analytical and bioanalytical chemistry·2026
Same author

Ionization efficiency prediction of electrospray ionization mass spectrometry analytes based on molecular fingerprints and cumulative neutral losses.

Journal of cheminformatics·2025
Same author

Do experimental projection methods outcompete retention time prediction models in non-target screening? A case study on LC/HRMS interlaboratory comparison data.

The Analyst·2025
Same author

Active Learning Improves Ionization Efficiency Predictions and Quantification in Nontargeted LC/HRMS.

Analytical chemistry·2025

Related Experiment Video

Updated: Mar 10, 2026

Characterizing Bacterial Volatiles using Secondary Electrospray Ionization Mass Spectrometry SESI-MS
08:54

Characterizing Bacterial Volatiles using Secondary Electrospray Ionization Mass Spectrometry SESI-MS

Published on: June 8, 2011

18.6K

pH Effects on Electrospray Ionization Efficiency.

Jaanus Liigand1, Asko Laaniste2, Anneli Kruve2

  • 1Institute of Chemistry, Faculty of Science and Technology, University of Tartu, Ravila 14A, 50411, Tartu, Estonia. jaanus.liigand@ut.ee.

Journal of the American Society for Mass Spectrometry
|December 15, 2016
PubMed
Summary
This summary is machine-generated.

Mobile phase pH significantly impacts electrospray ionization efficiency. Analyte properties, not just pKa, determine pH dependence, enabling better prediction of ionization behavior for mass spectrometry.

Keywords:
ESIElectrosprayIonization degreeIonization efficiencySolvent effectspH

More Related Videos

Absolute Quantitation of Inositol Pyrophosphates by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry
09:22

Absolute Quantitation of Inositol Pyrophosphates by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry

Published on: August 13, 2021

2.8K
Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
05:47

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry

Published on: February 19, 2020

10.1K

Related Experiment Videos

Last Updated: Mar 10, 2026

Characterizing Bacterial Volatiles using Secondary Electrospray Ionization Mass Spectrometry SESI-MS
08:54

Characterizing Bacterial Volatiles using Secondary Electrospray Ionization Mass Spectrometry SESI-MS

Published on: June 8, 2011

18.6K
Absolute Quantitation of Inositol Pyrophosphates by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry
09:22

Absolute Quantitation of Inositol Pyrophosphates by Capillary Electrophoresis Electrospray Ionization Mass Spectrometry

Published on: August 13, 2021

2.8K
Sample Preparation for Probe Electrospray Ionization Mass Spectrometry
05:47

Sample Preparation for Probe Electrospray Ionization Mass Spectrometry

Published on: February 19, 2020

10.1K

Area of Science:

  • Analytical Chemistry
  • Mass Spectrometry
  • Separation Science

Background:

  • Electrospray ionization (ESI) is a crucial technique in mass spectrometry.
  • Mobile phase composition, particularly pH, is known to influence ESI efficiency.
  • A systematic understanding of pH effects on analyte ionization is needed.

Purpose of the Study:

  • To investigate the dependence of analyte ionization efficiency on mobile phase pH.
  • To identify key physicochemical properties governing pH effects in ESI.
  • To develop predictive models for analyte ionization behavior.

Main Methods:

  • Studied the effect of aqueous phase pH on ESI efficiency for 28 diverse compounds.
  • Utilized linear discriminant analysis to correlate analyte behavior with physicochemical properties.
  • Evaluated parameters including pKa, ionization degree, charge centers, hydrogen bonding capacity, and polarity.

Main Results:

  • Neither pKa nor solution phase ionization degree alone sufficiently explained pH effects on ESI efficiency.
  • Distinguished pH-dependent and independent compounds using specific physicochemical parameters.
  • Observed that decreasing pH can enhance ionization efficiency by over two orders of magnitude.

Conclusions:

  • Analyte ionization efficiency in ESI is complexly related to mobile phase pH and intrinsic physicochemical properties.
  • Predictive models based on charge centers, hydrogen bonding capacity, polarity, and pKa can differentiate analyte responses.
  • Understanding these relationships is vital for optimizing ESI-MS methods for diverse analytes.