10.1021/la063251f.s001 Carolyn M. McQuaw Carolyn M. McQuaw Leiliang Zheng Leiliang Zheng Andrew G. Ewing Andrew G. Ewing Nicholas Winograd Nicholas Winograd Localization of Sphingomyelin in Cholesterol Domains by Imaging Mass Spectrometry American Chemical Society 2007 sphingomyelin phase fluorescence microscopy literature results show label phospholipid Localization Cholesterol Domains laterally coexisting immiscible palmitoyloleoylphosphatidylcholine lipid ion mass spectrometry Imaging Mass SpectrometryThe location imaging necessity segregation Sphingomyelin cholesterol domains SM localizes monolayer 2007-05-08 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Localization_of_Sphingomyelin_in_Cholesterol_Domains_by_Imaging_Mass_Spectrometry/3009076 The location of each lipid in a palmitoyloleoylphosphatidylcholine/18:0 sphingomyelin/cholesterol monolayer system is laterally resolved using imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS) without the necessity of adding fluorescent labels. This system of coexisting immiscible liquid phases shows cholesterol domains with sizes and shapes comparable to those in the fluorescence microscopy literature. The results show that SM localizes with cholesterol and that palmitoyloleoylphosphatidylcholine is excluded. Moreover, the segregation is not complete, and there is a small amount of both phospholipids distributed throughout.