Fig. 4: IM-MS-based four-dimensional sterol lipid analysis of biological samples.

a Subclass statistical analyses of the identified sterol lipids in human plasma (n = 3 technically replicated samples), mouse liver tissue (n = 6 biologically independent samples), and mouse brain tissue (n = 6 biologically independent samples for each group). Each sample was analyzed once by LC-IM-MS. b Numbers of identified sterol lipids with MSI level 1 and MSI level 2 in three sample types. c The identification of campesterol in brain tissue samples using the standard ST library through four-dimensional matching. d Validation of campesterol identification with the chemical standard. e The identification of 14-demethyllanosterol in brain tissue sample using the extended ST library through four-dimensional matching. f Validation of the 14-demethyllanosterol identification with the chemical standard. g Fitted trend line and chemical space for sterol lipids as determined using a power function with the standard ST library (n = 97). h The distributions of the identified sterol lipids from three sample types in the chemical space of sterol lipids. Blue solid line, the trend line of sterol lipids. Black dash lines, the 99% predictive interval.