Quantification of Amine- and Alcohol-Containing Metabolites in Saline Samples Using Pre-extraction Benzoyl Chloride Derivatization and Ultrahigh Performance Liquid Chromatography Tandem Mass Spectrometry (UHPLC MS/MS)

Dissolved metabolites serve as nutrition, energy, and chemical signals for microbial systems. However, the full scope magnitude of these processes in marine systems are unknown, largely due to insufficient methods, including poor extraction small, polar compounds using common solid-phase resins. Here, we utilized pre-extraction derivatization ultrahigh performance liquid chromatography electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) detect quantify targeted dissolved seawater saline culture media. Metabolites were derivatized with benzoyl chloride by their primary secondary amine alcohol functionalities quantified stable isotope-labeled internal standards (SIL-ISs) produced from 13C6-labeled chloride. We optimized derivatization, extraction, sample preparation field samples evaluated matrix-derived biases. have this quantitative method 73 metabolites, which 50 cannot be without low efficiencies. Of 66 identified either media or 45 those quantified. This is sensitive (detection limits = pM nM), rapid (?5 min per sample), high throughput.