Online UV-induced ozone reactions coupled with ESI-MS for C=C bond determination in unsaturated lipids

摘要

The C=C bond in unsaturated phospholipids and fatty acids is an important structural component and has a profound impact on biological function. Ozone reaction with C=C bond has been demonstrated as an effective means for the determination of C=C location in unsaturated lipids either in solution or in gas-phase. Herein we describe an alternative electrospray ionization (ESI) MS method based on online ozone reaction with unsaturated lipids initiated by UV irradiation of the ESI solution. Under optimized conditions 90% product conversion was observed for ～1.5 seconds UV exposure of the solution phase, making this a simple and efficient method of inducing ozone reactions with unsaturated lipids for C=C identification.