Two-dimensional mass spectrometry in a linear ion trap, an in silico model

Area of Science:

• Analytical Chemistry
• Mass Spectrometry

Background:

• Two-dimensional mass spectrometry (2D MS) correlates precursor and product ions without isolation.
• Previously, 2D MS was limited to Fourier transform ion cyclotron resonance mass spectrometers.
• Linear ion traps (LITs) offer potential for 2D MS compatible with chromatography.

Purpose of the Study:

• To explore the feasibility of implementing 2D MS in linear ion traps (LITs).
• To develop a method for data-independent tandem mass spectrometry on a chromatographic timescale.

Main Methods:

• Utilized SIMION ion trajectory calculations to model 2D MS in a LIT.
• Applied stored waveform inverse Fourier transform techniques for radial ion excitation.
• Simulated laser-based fragmentation to analyze product ion abundances.

Main Results:

• Ion cloud sizes were modulated by resonant frequencies in the LIT.
• Product ion abundances correlated with precursor resonant frequencies after fragmentation.
• A simulated 2D mass spectrum was successfully obtained.

Conclusions:

• An in silico model confirms the feasibility of 2D MS in LITs.
• 2D MS in LITs allows for tandem mass spectrometry without ion isolation.
• This technique is compatible with liquid chromatography and gas chromatography timescales.