Novel Method for Simultaneously Untargeted Metabolome and Targeted Exposome Analysis in One Injection

technology; it allows for the simultaneous acquisition of the metabolome in HRMS and the exposome in multiple reaction monitoring (MRM) modes in one injection. The signal responses for exogenous compounds in MRM were comparable to those of metabolites in HRMS. This method was rigorously validated, and all exogenous standards had relative standard deviations (RSDs) below 20% for intraday and interday repeatability. Over 90% of metabolic features exhibited RSDs below 20% in these assessments. The method also had a broad quantification range, with lower limits of quantification (LLOQ) from 0.1 to 25 ng/mL and higher limits of quantification (HLOQ) from 2.5 to 1000 ng/mL. This approach was demonstratively applied to a type 2 diabetes mellitus cohort to identify serum risk factors and study the metabolome-exposome association. To our knowledge, this study is the first implementation of a unified method for the simultaneous analysis of endogenous metabolites in the untargeted mode and 210 exogenous compounds in the targeted mode in one injection, offering a novel tool for mEWAS research.