Ion confinement and separation using asymmetric electrodynamic fields in structures for lossless ion manipulations.

Area of Science:

• Analytical Chemistry
• Separation Science

Background:

• Traveling Wave-Sim (TW-SLIM) ion mobility separations offer high resolution using mirrored electrode surfaces for symmetric electric fields.
• Previous research suggests symmetric fields may not be essential for planar ion optics.

Purpose of the Study:

• To investigate the feasibility of achieving ion mobility separations using asymmetric electric fields in a TW-SLIM instrument.
• To explore the impact of asymmetric fields on ion transmission, separation quality, and instrument design.

Main Methods:

• Simulated an asymmetric field configuration in SIMION by applying a uniform DC potential to the top PCB electrodes of a TW-SLIM.
• Modified a benchtop TW-SLIM instrument to implement the asymmetric field configuration.
• Assessed ion transmission, separation, and cycling capabilities with the modified instrument.

Main Results:

• Simulations confirmed full ion transmission across various m/z ratios and DC biases.
• The modified benchtop instrument successfully transmitted, separated, and cycled ions with minimal loss.
• Explored the effect of 'pusher' strength on separation and compared performance with standard TW-SLIM for neurotensin ion charge states.

Conclusions:

• A functional TW-SLIM instrument utilizing asymmetric confining fields was developed.
• Asymmetric field modifications offer a pathway to enhanced functionality with minimal disruption.
• A dedicated TW-SLIM PCB 'pusher' board could simplify manufacturing, assembly, and electronics while improving field consistency.