PL-classes were separated using a 7-step gradient-solvent sequence with a previous acid plate preconditioning, using Automated Multiple Development. Band zones of the plate corresponding to PL classes were selected to ensure their direct transfer to ion-trap MS equipment through an elution-based interface.
Under the studied conditions, ESI+-MS spectra of PC and CL mostly showed sodium adducts ([M?+?Na]+) and [M-2H?+?3Na]+, respectively, when recorded from the plate. The respective sodium adducts were fragmented in the ion-trap, and sodium remained as the charge of the fragment ions, thus being useful for their structural identification through MS/MS. ESI--MS and MS/MS spectra of CL were also obtained as [M-2H]2?, as well as those of PE and PG species as [M-H]- and [M]?, respectively.
In this way, relative composition profiles of each studied PL-class by ESI-MS, and further identification of individual PL and the molecular species belonging to each of them by MS/MS were obtained. 相似文献