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Atmospheric pressure neutral reionization mass spectrometry for structural analysis
Pengyuan Liu1, Pengyi Zhao1, R Graham Cooks2
1Center for Intelligent Chemical Instrumentation , Department of Chemistry and Biochemistry , Edison Biotechnology Institute , Ohio University , Athens , OH , USA 45701 .
Chemical Science
|October 10, 2017
Summary
Atmospheric pressure neutral reionization mass spectrometry (APNR) detects neutral fragments lost in traditional methods. This technique enhances structural analysis of biomolecules like peptides and saccharides by providing complementary data to existing methods.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Mass Spectrometry
Background:
- Tandem mass spectrometry (MS) typically detects only charged fragments, losing neutral fragments during ion dissociation.
- This limitation hinders comprehensive structural analysis of biomolecules.
Purpose of the Study:
- To develop a novel mass spectrometry technique, atmospheric pressure neutral reionization mass spectrometry (APNR), to detect neutral fragments.
- To demonstrate the utility of APNR for structural elucidation of diverse biomolecules and unimolecular dissociation mechanisms.
Main Methods:
- Analyte ions undergo atmospheric pressure thermal dissociation (APTD) followed by soft reionization using electrosonic spray ionization (ESSI).
- The APNR technique was applied to peptides, saccharides, nucleotides, and synthetic drugs.
Main Results:
- APNR successfully detected neutral fragments, including phosphorylated riboses and indoles, confirming proposed dissociation mechanisms.
- Extensive fragment ions, such as y ions in peptides and cross-ring cleavages in saccharides, were observed, aiding sequencing and linkage site identification.
- Direct disulfide bond cleavage in peptides during APTD facilitated sequencing and mapping.
Conclusions:
- APNR is a powerful tool for the structural analysis of biomolecules, offering complementary information to collision-induced dissociation (CID).
- The technique aids in differentiating isomers and elucidating complex dissociation pathways.
- APNR, coupled with APTD, holds significant value for biomolecular structure determination.
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