Proposed Sessions
Day 2, June 11（Thu.） 10:00-10:15 Room D (5F 511+512)
- 2D-P1-1000
Visualization of Phospholipid sn-Positional Isomers in the Brain Using Cyclic Ion mobility Mass Spectrometry Imaging
(1TUMSAT, 2Nihon Waters, 3Fukushima Univ., 4Chubu Univ., 5UOsaka)
oSeiya Tanaka1, Emi Sasaki1, Taiji Kawase2, Thanai Paxton2, Kenji Hirose2, Aya Kiriake3, Kazuaki Yoshinaga3, Yugo Iwasaki4, Naohiro Gotoh1, Katsuyoshi Masuda5
Docosahexaenoic acid (DHA, 22:6)-containing phospholipids are vital for brain function, yet the localization of their sn-positional isomers remains poorly understood due to analytical limitations. This study demonstrates a breakthrough in resolving lipid sn-isomers including PC, PE, PS, and their precursor DAG using cyclic ion mobility mass spectrometry (cIM-MS). While conventional ion mobility often fails to separate these isomers without chromatography, we achieved successful resolution of PC(22:6/16:0) and PC(16:0/22:6) by optimizing the cyclic cell to 30 passes. Application of this cIM-MS imaging to 4-week-old male ICR mouse brain sections revealed distinct regional distributions: PC(22:6/16:0) predominantly accumulated in the inferior colliculus and brainstem, whereas PC(16:0/22:6) was concentrated in the olfactory bulb. These imaging findings were rigorously confirmed by LC-MS/MS quantification of dissected brain regions. This work establishes cIM-MS as a powerful tool for lipid analysis, enabling the identification of isomer-specific localization in complex biological tissues.