Supercritical fluid chromatography-tandem mass spectrometry for the analysis of lipid A
Although supercritical fluid chromatography (SFC) is often useful for the analysis of nonpolar lipids, this study demonstrates for the first time an analytical SFC method with detection by ion trap mass spectrometry (MS/MS) for large and polar lipids, such as lipid A, using a simple, fast, economical, and environmentally-friendly approach. Chemical derivatization of the lipid A was not needed, and the SFC-MS/MS analysis only took 2 min per injection. The method was evaluated by analyzing lipid A spiked into two representative food matrices, lettuce and ground beef. For sample preparation, a simple shaking procedure with 3/1 (v/v) chloroform–methanol was used. %Recoveries in spiked samples were 74 ± 10 at 10–30 μg g−1 in lettuce and 110 ± 5 in meat at 30 μg g−1.