A versatile method to separate complex lipid mixtures using 1-butanol as eluent in a reverse-phase UHPLC-ESI-MS system

• Published in: Chemistry and physics of lipids 2021-10, Vol.240, p.105125-105125, Article 105125
• Main Authors: de Kok, Niels A.W., Exterkate, Marten, Andringa, Ruben L.H., Minnaard, Adriaan J., Driessen, Arnold J.M.
• Format: Article
• Language: English
• Subjects: 1-Butanol - chemistry; Cardiolipin; Chromatography, High Pressure Liquid; Electrospray ionization mass spectrometry (ESI-MS); Lipidomics; Lipids - chemistry; Phospholipid; Reversed-phase liquid chromatography (RPLC); Spectrometry, Mass, Electrospray Ionization; Tetraether lipid
• ISSN: 0009-3084; 1873-2941
• DOI: 10.1016/j.chemphyslip.2021.105125

•1-butanol instead of 2-propanol as organic mobile phase in RPLC separations extends elution capabilities.•The 1-butanol based method allows for separation of a large range of lipids with different hydrophobicities.•Effective separation of complex biological lipid mixtures demonstrates the versatility of the method for lipidomic analyses.•A complex mixture of cardiolipins elutes in clusters dependent on the number of carbon atoms in the acyl chain.•Isobaric diester and cardiolipin lipid species separation allows for more detailed acyl chain analysis. Simple, robust and versatile LC–MS based methods add to the rapid assessment of the lipidome of biological cells. Here we present a versatile RP-UHPLC-MS method using 1-butanol as the eluent, specifically designed to separate different highly hydrophobic lipids. This method is capable of separating different lipid classes of glycerophospholipid standards, in addition to phospholipids of the same class with a different acyl chain composition. The versatility of this method was demonstrated through analysis of lipid extracts of the bacterium Escherichia coli and the archaeon Sulfolobus acidocaldarius. In contrast to 2-propanol-based methods, the 1-butanol-based mobile phase is capable of eluting highly hydrophobic analytes such as cardiolipins, tetraether lipids and mycolic acids during the gradient instead of the isocratic purge phase, resulting in an enhanced separation of cardiolipins and extending the analytical range for RPLC.