Timed relay contact closure controlled system for parallel second dimensions in multi-dimensional liquid...

Area of Science:

• Analytical Chemistry
• Chromatography
• Lipidomics

Background:

• Conventional two-dimensional liquid chromatography (2D-LC) struggles to resolve short-chain triacylglycerols (TAGs) in biological samples.
• Existing methods using C18 columns or silver ion chromatography as the second dimension lack sufficient separation power for these complex lipid mixtures.

Purpose of the Study:

• To develop and implement a novel three-dimensional liquid chromatography (3D-LC) system for enhanced separation of short-chain TAGs.
• To overcome the limitations of existing 2D-LC techniques in resolving complex lipid profiles.

Main Methods:

• Development of hardware and software for a three-dimensional separation system.
• Utilized two contact closure (CC) activated 4-port, 2-position valves (4P2PVs) for ultra-high performance liquid chromatography (UHPLC).
• Implemented a timed contact closure circuit (TCCC) to control valve switching for comprehensive 2D-LC coupled to four mass spectrometers (LC3MS4 configuration).

Main Results:

• Successfully established a 3D-LC system enabling enhanced resolution of TAGs.
• The first dimension utilized non-aqueous reversed-phase HPLC for TAG separation.
• The second dimension employed silver-ion chromatography for unsaturated TAGs, while a CC-controlled UHPLC served as the second second-dimension for short-chain saturated TAGs.

Conclusions:

• The developed 3D-LC system provides superior resolution for short-chain TAGs compared to conventional 2D-LC methods.
• This advancement offers a powerful tool for detailed lipidomic analysis of biological samples.
• The innovative use of TCCC-controlled UHPLC valves expands the capabilities of 2D-LC systems.