Phospholipid composition analysis of krill oil through HPLC with ELSD: Development, validation, and comparison with 31P NMR spectroscopy

A method wherein a high-performance liquid chromatography (HPLC) system is combined with an evaporative light scattering detector (ELSD) was developed and validated as an alternative to the official phosphorous-31 nuclear magnetic resonance (31P NMR) technique to analyze phospholipids in krill oil. A quadratic calibration curve with a good correlation coefficient (>0.999) in the 100–1000 μg mL−1 range was obtained for each phospholipid. The limit of detection (2–7.5 μg mL−1) of the designed assay for the phospholipids in krill oil was good, and the accuracy (99.6–101.0 %) was excellent. The relative standard deviations for repeatability (<1%) and intermediate precision (2.3 %–6.9 %) were acceptable. The results of the developed HPLC-ELSD method applied to krill oil samples were in agreement with those of 31P NMR spectroscopy. Moreover, statistical comparison indicated no significant difference between two methods. Thus, the HPLC-ELSD method can be applied for analyzing the phospholipid composition of krill oil.