119th General Meeting of the KCS

Type Oral Presentation
Area Oral Presentation of Young Analytical Chemists Ⅰ
Room No. 303호
Time THU 09:46-:
Code ANAL1.O-16
Subject Enhanced quantification of phospholipids using isotope-labeled methylation using nUPLC-ESI-MS/MS
Authors 이종철, 변슬기, 문명희*
연세대학교 화학과, Korea
Abstract Phospholipid (PL) is one of the most important type among various lipid classes in biological cells. Quantitative analysis of PLs is crucial as they regulate several important functions such as formation of cell membrane, intercellular signaling, and energy storage. Conventionally, lipid quantitation using LC-MS is often carried out with the addition of internal standards to compensate the ionization fluctuation. However, the use of internal standards is limited by several reasons; lipid standards of various molecular structures are limited and accurate determination of lipid amount is difficult. In this study, a quantitative analysis of PLs was accomplished, based on an isotope-labeled methylation (ILM) method using (trimethylsilyl)diazomethane as a methylation reagent to methylate the phosphate or carboxyl group. MeOH and HCl were utilized for light isotope-labeled methylation, while MeOD and DCl containing deuterium were used for counterpart methylation. ILM method was validated concerning efficiency of methylation, optimization of modifiers, and peak area linear relationship of H- and D- labeled methylated lipids. This method consequently applied to DU145 cell line with and without D-allose treatment. In the end, a total of 112 PLs including LPG, PG, LPS, PS, LPA, PA, and CL were identified. Among these lipids, 8 and 25 more PAs and CLs, respectively, were detected from ILM method, when they were not detected in intact lipid extracts.
E-mail jchul@yonsei.ac.kr