Charge Detection Mass Spectrometry with Almost Perfect Charge Accuracy.

Area of Science:

• Analytical Chemistry
• Mass Spectrometry

Background:

• Charge detection mass spectrometry (CDMS) is a single-particle technique for determining ion masses.
• CDMS offers advantages like no upper mass limit and analysis of complex mixtures.
• Previous limitations in CDMS were due to poor charge measurement accuracy, hindering mass resolution.

Purpose of the Study:

• To improve the accuracy of charge measurement in CDMS.
• To enhance the mass resolution achievable with CDMS.
• To enable precise assignment of ions to their correct charge states.

Main Methods:

• Reduced pressure to extend ion trapping time.
• Implemented a novel analysis method to improve signal-to-noise ratio.
• Developed a method to compensate for charge measurement imperfections.

Main Results:

• Achieved unprecedented charge measurement uncertainty of less than 0.20 e root-mean-square deviation.
• Resolved distinct peaks for different charge states in the charge spectrum.
• Reduced the fraction of ions assigned to the wrong charge state to 6.4 × 10(-5).

Conclusions:

• The enhanced charge measurement precision in CDMS significantly improves mass resolution.
• Mass uncertainty is now primarily limited by the mass-to-charge ratio measurement.
• CDMS is now capable of highly accurate single-particle mass determination.