Separation of Galactosyl and Glucosylceramide Isomers Using the SELECT SERIES™ Cyclic™ IMS

Importance of the Topic

Galactosylceramide and glucosylceramide are epimeric lipids with crucial roles in physiology and pathology. Their structural similarity makes them challenging to distinguish using conventional lipid analysis. High confidence separation of these isomers is vital for understanding lipid function and disease mechanisms.

Study Objectives and Overview

This study aims to evaluate the capacity of the SELECT SERIES Cyclic IMS to resolve GalCer and GlcCer isomers by exploiting its multi-pass ion mobility capability. An equimolar mixture of standard lipids is used to assess resolution at different numbers of mobility passes.

Methodology

Sample preparation involved standard GalCer and GlcCer dissolved in chloroform methanol water and infused at five microliters per minute into an electrospray source. The deprotonated ion at m/z 726.54 was isolated in the quadrupole and introduced into the cyclic mobility cell. The number of passes was varied from one to twenty to scale ion mobility resolution. Operating parameters included negative ion mode, capillary voltage two kilovolts, cone voltage thirty volts and traveling wave settings optimized for ion mobility separation.

Instrumentation

• SELECT SERIES Cyclic IMS for high resolution ion mobility separation
• MassLynx 4.2 software for data acquisition and analysis

Key Results and Discussion

Arrival time distributions showed no separation at one pass resolution approx sixty five marginal separation at five passes resolution approx one hundred forty five and about fifteen percent valley at ten passes resolution approx two hundred five. Complete baseline resolution was achieved at twenty passes with resolution near two hundred ninety demonstrating the multi-pass capability can scale to meet challenging isomer separations. Minor signals in individual analyses indicated trace stereoisomer impurities in the standards.

Benefits and Practical Applications

• Unambiguous separation of structurally similar lipid isomers
• Rapid analysis with millisecond ion mobility timescale
• Potential for impurity profiling in lipid standards

Future Trends and Potential Applications

Integration of cyclic IMS into lipidomics workflows promises enhanced structural characterization of complex lipid mixtures. Advances in automation and coupling with chromatography could extend applications to biological samples, disease biomarker discovery and quality control in pharmaceutical and food industries.

Conclusion

The SELECT SERIES Cyclic IMS with multi-pass ion mobility provides adjustable resolution up to baseline separation of GalCer and GlcCer epimers. This capability addresses a critical challenge in lipidomics and opens opportunities for detailed isomeric analysis in research and applied settings.

References

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3. Reza S Ugorski M and Suchanski J Glucosylceramide and Galactosylceramide Small Glycosphingolipids with Significant Impact on Health and Disease Glycobiology 2021 31 1416 1434