A linear ion trap mass spectrometer with versatile control and data acquisition for ion/ion reactions

Area of Science:

• Analytical Chemistry
• Mass Spectrometry
• Biochemistry

Background:

• Top-down protein analysis requires sophisticated mass spectrometry techniques.
• Ion/ion reactions are crucial for characterizing intact proteins and their modifications.
• Existing instrumentation can be complex and costly, limiting accessibility.

Purpose of the Study:

• To construct a simplified and accessible linear ion trap (LIT) for top-down proteomics.
• To integrate electrospray ionization (ESI) and atmospheric sampling glow discharge ionization (ASGDI) for versatile ion generation.
• To enable a broad range of gas-phase ion/ion reaction studies on intact proteins.

Main Methods:

• Construction of a linear ion trap (LIT) with simplified electronics.
• Coupling of electrospray ionization (ESI) for protein delivery and ASGDI for reagent ion generation.
• Utilizing mass-selective axial ejection for mass spectrometry and ion manipulation.

Main Results:

• Achieved high trapping efficiencies for protein ions, ranging from 70% to 90%.
• Demonstrated the capability to perform proton transfer reactions on intact protein ions.
• Successfully executed various ion/ion reaction modes, including dual polarity storage, transmission, and ion parking.

Conclusions:

• The developed LIT-ESI-ASGDI system is a versatile platform for top-down protein analysis.
• The instrument's simplified design promotes wider dissemination and accessibility for ion/ion reaction studies.
• The system effectively facilitates gas-phase ion chemistry on intact proteins, advancing proteomic research.