A simple liquid extraction protocol for overcoming the ion suppression of triacylglycerols by phospholipids in liquid chromatography mass spectrometry studies

• A liquid–liquid extraction protocol for regiospecific analysis of triacylglycerol by LC–MS/MS without suspicion of ion suppression by phospholipids is proposed.
• The rationale of the protocol is demonstrated by means of HPTLC and LC–MS/MS.
• The ability of the proposed liquid–liquid extraction protocol to separate phospholipids from triacylglycerols is demonstrated by using biological samples.

It is well-known that triacylglycerol (TAG) ions are suppressed by phospholipid (PL) ions in regiospecific analysis of TAG by mass spectrometry (MS). Hence, it is essential to remove the PL during sample preparation prior to MS analysis. The present article proposes a cost-effective liquid–liquid extraction (LLE) method to remove PL from TAG in different kinds of biological samples by using methanol, hexane and water. High performance thin layer chromatography confirmed the lack of PL in krill oil and salmon liver samples, submitted to the proposed LLE protocol, and liquid chromatography tandem MS confirmed that the identified TAG ions were highly enhanced after implementing the LLE procedure.

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