Analytical separations for lipids in complex, nonpolar lipidomes using differential mobility spectrometry

Area of Science:

• Lipidomics
• Analytical Chemistry
• Biochemistry

Background:

• Meibum, eyelid secretions, contains complex nonpolar lipids with long acyl chains.
• Analyzing the meibum lipidome is challenging due to poor chromatographic resolution of neutral lipid classes.

Purpose of the Study:

• To apply differential mobility spectrometry coupled with mass spectrometry (DMS-MS) for analyzing the human meibum lipidome.
• To achieve high-resolution separation of nonpolar lipid classes within meibum.

Main Methods:

• Utilized differential mobility spectrometry-mass spectrometry (DMS-MS) to analyze human meibum.
• Exploited ion mobility behavior to resolve and characterize wax esters and cholesteryl esters based on acyl chain length and unsaturation.

Main Results:

• Achieved near-baseline resolution of wax esters and cholesteryl esters in meibum.
• Demonstrated structure-mobility relationships correlating ion mobility with acyl chain length and unsaturation.
• Extended meibum lipidome coverage by profiling molecular speciation within lipid classes.

Conclusions:

• Differential ion mobility is a powerful orthogonal separation technique for neutral lipids in complex matrices like meibum.
• DMS-MS can predict lipid physicochemical properties, potentially aiding in understanding their biological functions.