Evaluating Novel Direct Injection Liquid Chromatography-Mass Spectrometry Method and Extraction-Based Workflows for...

Area of Science:

• Biochemistry
• Analytical Chemistry
• Molecular Biology

Background:

• Lipids within extracellular vesicles (EVs) are critical for biological functions and implicated in carcinogenesis.
• Current lipid extraction methods for EV lipidomics can be laborious and may introduce variability.

Purpose of the Study:

• To compare established lipid extraction techniques with a novel direct injection liquid chromatography-mass spectrometry (DI-LC-MS) workflow for EV lipidomics.
• To evaluate the efficiency, precision, and lipidome coverage of the DI-LC-MS method.

Main Methods:

• Comparison of liquid-liquid extraction, single-phase extraction, and solid-phase extraction against a DI-LC-MS workflow.
• The DI-LC-MS approach involves direct disruption and analysis of EV lipids within the chromatographic system.
• Profiling of lipids in mammalian and bacterial EVs using the developed DI-LC-MS method.

Main Results:

• The DI-LC-MS workflow demonstrated high precision (CV < 20%) and good lipidome coverage for EV samples.
• Significant differences in lipid profiles were identified between EV samples using the DI-LC-MS method.
• The DI-LC-MS method showed column stability suitable for comparative lipidomic studies.

Conclusions:

• DI-LC-MS is a sustainable and efficient alternative for EV lipidomics, eliminating the need for sample preparation.
• This method reduces analysis time, solvent consumption, and chemical noise, requiring minimal sample volume (< 1 μL).
• The DI-LC-MS workflow provides a robust platform for comparative lipidomic analyses of extracellular vesicles.