Parallel detection in a single ICR cell: Spectral averaging and improved S/N without increased acquisition time

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Physical Chemistry

Background:

• Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) offers high resolving power and mass accuracy.
• Signal-to-noise ratio (S/N) is a critical performance metric in FTICR-MS.
• Conventional methods to improve S/N, like serial signal averaging, increase acquisition time and limit compatibility with techniques such as chromatography.

Purpose of the Study:

• To investigate parallel signal acquisition as a method to enhance S/N in FTICR-MS.
• To evaluate the impact of parallel detection on resolving power and sensitivity.
• To assess the practicality of parallel detection for improving FTICR-MS performance.

Main Methods:

• Utilized a single ICR cell equipped with 4 pairs of dipole detection electrodes, each connected to an independent pre-amplifier.
• Acquired 4 spectra in parallel using the multiple electrode pairs.
• Averaged the 4 parallel-acquired spectra to assess S/N improvement.

Main Results:

• Parallel signal acquisition with 4 detector pairs yielded a 1.76-fold higher S/N compared to a single detector pair.
• No observable loss in resolving power (maintained at 100,000) was detected with parallel detection.
• The parallel detection approach achieved improved S/N without requiring multiple ion accumulation or serial excitation/detection events.

Conclusions:

• Parallel detection with multiple electrode pairs and pre-amplifiers is a viable strategy for enhancing S/N and sensitivity in FTICR-MS.
• This parallel detection method offers a practical alternative to serial signal averaging, particularly in applications where extended acquisition times are not feasible.
• The findings suggest broad applicability for parallel detection in future FTICR-MS instrumentation design.