Ion isolation and multigenerational collision-induced dissociation using the inverse Mathieu q scan

Area of Science:

• Analytical Chemistry
• Mass Spectrometry

Background:

• Developing mass spectrometers with AC frequency scanning for ion manipulation.
• Utilizing inverse Mathieu q scan functions for ion isolation, activation, and ejection.

Purpose of the Study:

• To demonstrate AC frequency scanning as a viable alternative to RF amplitude ramps in ion trap mass spectrometry.
• To enable mass-selective operations including ion isolation, activation, and ejection.

Main Methods:

• Ion isolation via frequency hopping during frequency sweeps.
• Multigenerational collision-induced dissociation by scanning excitation frequency (low to high).
• Optimized fragmentation using inverse Mathieu q scan for higher product ion abundance.

Main Results:

• Achieved >70% isolation efficiency for single and nonadjacent mass-to-charge (m/z) ions.
• Demonstrated fragmentation of caffeine and noroxycodone.
• Observed multiple generations of product ions from noroxycodone fragmentation.

Conclusions:

• AC frequency scanning can replace RF amplitude ramps for all mass-selective operations in ion trap mass spectrometers.
• This approach offers a novel method for controlling ion behavior within mass spectrometers.