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Updated: Jul 26, 2026
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Nuclear Magnetic Resonance Spectroscopy for the Identification of Multiple Phosphorylations of Intrinsically Disordered Proteins
Published on: December 27, 2016
Insights into the cITP process using on-line NMR spectroscopy.
Andrew M Wolters1, Dimuthu A Jayawickrama, Cynthia K Larive
1Department of Chemistry and the Beckman Institute, University of Illinois, Urbana 61801, USA.
Analytical Chemistry
|August 30, 2002
Summary
This study demonstrates how nuclear magnetic resonance (NMR) can noninvasively monitor capillary isotachophoresis (cITP) processes. NMR provides real-time diagnostic information, including pD and temperature, during cITP analysis.
Area of Science:
- Analytical Chemistry
- Separation Science
- Spectroscopy
Background:
- Capillary isotachophoresis (cITP) is coupled with nuclear magnetic resonance (NMR) for analyzing dilute charged analytes.
- Microcoil NMR probes offer enhanced mass sensitivity for optimal detection in cITP/NMR.
- Previous studies utilized deuterated buffers, limiting real-time monitoring.
Purpose of the Study:
- To investigate the noninvasive diagnostic capabilities of NMR for examining the cITP process.
- To utilize a 1H NMR observable leading electrolyte for tracking cITP progression.
- To establish on-line monitoring of cITP parameters like pD and temperature.
Main Methods:
- Coupling of capillary isotachophoresis (cITP) with 1H NMR spectroscopy.
- Employing tetramethylammonium acetate as a 1H NMR observable leading electrolyte.
- Using tert-butyl alcohol as an internal reference for chemical shift and line width measurements.
Main Results:
- The 1H chemical shift of acetate methyl resonance was used for on-line pD determination.
- Intracapillary temperature was measured via the HOD chemical shift.
- NMR simultaneously provided quantitative concentrations of leading ion, sample, and counterion.
Conclusions:
- NMR offers unique, noninvasive diagnostic capabilities for real-time monitoring of cITP.
- The developed cITP/NMR method allows for simultaneous quantitative analysis and process monitoring.
- This approach enhances the understanding and application of capillary isotachophoresis.
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