Resolution of Isomeric Mixtures in Ion Mobility Using a Combined Demultiplexing and Peak Deconvolution Technique

Area of Science:

• Analytical Chemistry
• Spectrometry
• Biochemistry

Background:

• Ion mobility measurements are crucial for separating and identifying isomers.
• Improving sensitivity and resolution in ion mobility-mass spectrometry (IM-MS) remains a challenge.
• Existing methods may not fully resolve complex isomeric mixtures.

Purpose of the Study:

• To develop and validate a combined data acquisition and processing strategy for enhanced ion mobility measurements.
• To improve the sensitivity and resolution of drift tube IM-MS.
• To demonstrate the capability of resolving challenging isomeric mixtures.

Main Methods:

• Implementation of an ion multiplexing strategy for signal gain (up to 8-fold).
• Application of a novel postacquisition data reconstruction technique: high resolution demultiplexing (HRdm).
• Investigation of biologically relevant isomeric mixtures, including lipids and carbohydrates.

Main Results:

• HRdm successfully resolved complex isomeric mixtures, including monosaccharide regioisomers with 0.8% drift time difference.
• Five out of six components were resolved in a complex trisaccharide isomer mixture.
• Effective resolving power (Rp) of 180-250 was achieved with HRdm.
• Analysis time and measurement precision remained unaffected, allowing direct determination of collision cross section values.

Conclusions:

• The combined strategy significantly improves resolution in the ion mobility dimension.
• HRdm is effective for resolving challenging isomers in biologically relevant samples.
• This approach enhances IM-MS capabilities without compromising analytical efficiency.