Multistage Linear Frequency Scanning Mass Analysis Processed by Fractional Fourier Transform.

Area of Science:

• Analytical Chemistry
• Spectrometry

Background:

• Linear ion trap mass spectrometry commonly uses resonance excitation for mass analysis.
• Signal smoothing in electronic systems limits mass resolution by broadening ejection signals.
• Scan rates and sample types differentially affect peak width and mass resolution.

Purpose of the Study:

• To improve mass resolution and extend the mass range in linear ion trap mass spectrometry.
• To mitigate ghost peaks caused by scattered ion ejection.
• To address limitations imposed by bandwidth-limited electronic systems.

Main Methods:

• Experiments conducted on a miniature linear ion trap mass spectrometer at varying scan rates.
• Implementation of a multistage linear frequency scanning mode.
• Application of fractional Fourier transform for processing ion ejection signals.

Main Results:

• Achieved a peak width of 0.84 Da at m/z 242 with a scan rate of 8000 Da/s.
• Demonstrated improved mass resolution compared to conventional methods.
• Successfully mitigated the impact of ghost peaks.

Conclusions:

• The proposed signal processing method enhances mass resolution and extends the mass range.
• Fractional Fourier transform effectively processes ejection signals for improved analytical performance.
• This technique offers a viable solution for overcoming bandwidth limitations in ion trap mass spectrometry.