Real Time Lipidomic Profiling Using Desorption Ionization with Ion Mobility MS

Importance of the Topic

Lipids play critical roles in food quality, nutrition, and cellular physiology. Variations in lipid composition affect caloric content, texture, taste, and are linked to diseases in plants and humans. Rapid and spatially resolved lipid profiling can improve diagnostics, food analysis, and personalized medicine.

Objectives and Study Overview

This study introduces a rapid, real-time method combining desorption ionization with ion mobility spectrometry–mass spectrometry to profile lipids directly from samples without chromatography. Representative samples include edible oils and human sebum from skin.

Experimental Methodology and Instrumentation

• Sample Preparation: Simple swiping of samples on glass capillaries; no extraction or derivatization.
• Ionization: Direct Analysis in Real Time source in both positive and negative modes.
• Mass Spectrometry: Waters SYNAPT G2 HDMS with T-Wave ion mobility cell.
• Operating Conditions: DART temperature 50–450 °C, cone voltage 20 V, acquisition range 50–1200 m/z, acquisition time 5–10 s.
• Data Processing: HDMS Compare Software for overlaying driftograms and targeted ion monitoring.

Main Results and Discussion

DART-IMS-TOF analysis delivered full lipid profiles in seconds. Characteristic drift times separated lipids by size, shape, and unsaturation level, resolving isobaric species without chromatography. Three-dimensional molecular maps of drift time, exact mass, and intensity enabled discrimination of key fatty acids such as EPA and DHA, as well as ceramides. Comparative studies of fish oil versus olive oil and sebum from different individuals revealed distinct lipid signatures.

Benefits and Practical Applications

• Eliminates laborious sample preparation and chromatographic steps.
• Enables rapid phenotypic fingerprinting and comparative lipidomics.
• Applicable to food quality control, clinical diagnostics, personalized medicine, and analysis of traditional medicines.

Future Trends and Applications

Emerging developments may include integration with other ambient ionization methods, automation for high-throughput screening, expansion to additional biomolecule classes, and coupling with machine learning to enhance data interpretation and predictive diagnostics.

Conclusion

The combination of desorption ionization and ion mobility-TOF mass spectrometry provides a fast, solvent-free, high-resolution platform for lipidomic profiling with wide-ranging applications across food science, clinical research, and industrial analytics.

References

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