Coupling corona discharge for ambient extractive ionization mass spectrometry

Area of Science:

• Analytical Chemistry
• Mass Spectrometry
• Chemical Sensing

Background:

• Traditional extractive electrospray ionization (EESI) requires specific conditions for analyte ionization.
• Analyzing complex matrices often necessitates extensive sample pretreatment.
• Simultaneous detection of polar and non-polar compounds remains a challenge.

Purpose of the Study:

• To develop a novel extractive ionization technique using corona discharge.
• To enable direct analysis of raw samples without pretreatment.
• To achieve sensitive detection of both polar and non-polar analytes in complex matrices.

Main Methods:

• Utilized corona discharge to generate highly charged microdroplets from a neutral solvent spray.
• Employed ambient condition ionization for direct impact on a neutral sample plume.
• Operated in positive ion mode for detection of molecular radical cations (non-polar) and protonated molecular ions (polar).

Main Results:

• Successfully generated molecular radical cations for non-polar compounds (e.g., benzene) and protonated molecular ions for polar compounds (e.g., acetonitrile).
• Demonstrated tolerance for complex matrices by dispensing the matrix in a large space.
• Achieved higher compound detection in lily fragrances compared to EESI and acceptable RSD (8.9%) for explosives detection (10 ppb) in wastewater.

Conclusions:

• The corona discharge-based method provides a sensitive and rapid approach for analyzing diverse analytes in complex samples.
• This technique eliminates the need for sample pretreatment, simplifying the analytical workflow.
• The method shows significant promise for the broad application in rapid detection across various fields.