Targeted Lipidomics Using the ionKey/MS System

Significance of the Topic

Lipidomics enables comprehensive profiling of hundreds of lipid species that play critical roles in physiological regulation and disease pathways.

Objectives and Study Overview

This study evaluates the ionKey/MS System for fast, sensitive lipidomic analysis with reduced solvent use and improved robustness.

Methodology and Instrumentation

The system integrates a Waters ACQUITY UPLC M-Class, ionKey Source, Xevo TQ-S MS, and an iKey CSH C18 microfluidic separation device (150 µm × 100 mm, 1.7 µm particles) operating at 2 µL/min and 55 °C.
Key LC conditions:

• Mobile phase A: ACN/H2O (60/40) with 10 mM ammonium formate and 0.1% formic acid
• Mobile phase B: IPA/ACN (90/10) with same additives
• Gradient from 55% A to 1% A over 16 min, total run 18 min

MS was operated in positive ESI MRM mode to monitor 215 lipid species across nine classes.

Main Results and Discussion

The microfluidic setup achieved chromatographic performance comparable to standard 2.1 mm columns while reducing solvent consumption by up to 200× and increasing sensitivity up to 10×.
Targeted MRM assays spanned five orders of dynamic range, effectively separating lipids by acyl chain length and degree of unsaturation.

Benefits and Practical Applications

• High-throughput profiling of complex lipidomes with low sample volumes (0.2–0.5 µL)
• Enhanced detection of low-abundance lipids in biofluids and tissues
• Reduced solvent costs and environmental impact

Future Trends and Opportunities

Integration of microfluidic LC-MS platforms will advance high-resolution lipidomics workflows and enable multi-omics analyses.
Ongoing developments may include wider lipid class coverage, higher multiplexing, and automation for clinical and industrial applications.

Conclusion

The ionKey/MS System demonstrates robust, sensitive, and efficient targeted lipidomics, offering significant advantages in solvent reduction and analytical performance for large-scale studies and low-abundance lipid detection.

References

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