Abstract: An analytical method for the determination of phospholipids contents in bell pepper by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established. Samples were extracted with isopropanol-methanol-water and the extract was purified by liquid-liquid extraction, and then separated on a hydrophilic interaction liquid chromatography (HILIC) (2.1 mm × 100 mm, 1.7 μm) system before being analyzed by electrospray ionization tandem quadrupole mass spectrometry. Relative quantification was carried out with phosphatidylcholine (PC), lysophosphatidylamide ethanolamine (LPE), lysophosphatidylcholine (LPC), phosphatidylglycerol (PG), phosphatidyl amide glycerol (PA), and lysophosphatidyl amide serine (LPS) as reference materials, separately. The extraction solvent and the purification method were selected in the experiment. The pretreatment method that could extract the largest number and amount of phospholipids was used, and its applicability was tested. The results showed that good linearity was observed for the six phospholipids in the range of 10–1 000 ng/mL. The limits of detection (LODs) were 2–300 ng/mL, and the limits of quantitation (LOQs) were 10–1 000 ng/mL. At spiked levels of 125, 250, and 375 ng/mL, the recovery was 68.06%–84.17%, with relative standard deviations (RSDs) of 3.40%–9.60%. The method provides a reliable platform for the determination of phospholipids in bell pepper, and more broadly for research on cold injury based on membrane lipid metabolism.

Key words: bell pepper, phospholipid, ultra-high performance liquid chromatography-tandem mass spectrometry