Phosphonium Chloride-Enhanced Ionization for High-Throughput Screening and Imaging of Carbohydrate Metabolites: Unveiling Disruptors of Sugar Metabolism

Abstract

Carbohydrates with high structural complexity are involved in key biological processes and serve as susceptible targets of environmental metabolic disruptors. However, the lack of a high-throughput and sensitive method for profiling carbohydrates limits our mechanistic understanding of the disruption of sugar metabolic pathways. In this study, we found that postcolumn addition of 10 μM (chloromethyl)triphenylphosphonium chloride (Ph3(CH2Cl)PCl) enabled the efficient ionization of saccharides and sugar alcohols as [M+Cl]− adducts in high-resolution mass spectrometry analysis, lowering instrumental detection limits by an average of 4- to 767-fold. A nontargeted method for polyol-containing compounds (PCCs) was subsequently established by leveraging their characteristic chlorinated isotope patterns. Approximately 68 PCCs, including saccharides with a degree of polymerization of 1–15, sugar alcohols, nonglucosyl saccharides, O-glycosides, nucleosides, amino sugars, a purine base, and a vitamin, were identified from microbially rich samples such as beer and mouse cecal contents. The method successfully identified disrupted saccharides and nucleosides in the cecal contents of mice exposed to a bisphenol A replacement (TGSA). Ph3(CH2Cl)PCl-enhanced ionization was further found to enhance analytical sensitivity and expand the species coverage in mass spectrum imaging, broadening the range of detectable saccharides (e.g., di- and trisaccharides) in biological samples. The imaging method confirmed alterations of PCCs in the central nervous system and liver tissues by medium-chain chlorinated paraffins during fetal development. This study provides an effective tool for the quantification, identification, and imaging of PCCs to screen for environmental disruptors of sugar metabolism.