Amines and amino acids are biochemically and physiologically essential molecules. Metabolomic profiling of these molecules is challenging due to their poor retention on reversed-phase chromatographic media, adversely affecting their analysis by LC-MS/MS. Marfey's reagent is a chiral amine derivatizing agent developed initially for the chromatographic resolution of D- and L-amino acid isomers. In this study, we demonstrate the use of heavy atom isotope-labeled L-Marfey's reagent for the metabolomics resolution and identification of amines and amino acids. <sup>13</sup>C<sub>2</sub>-labeled L-Marfey's (HL-Mar) reagent was synthesized, followed by the derivatization of an amino acid standard mixture overnight. A corresponding light L-Marfey's (LL-Mar) derivatized sample was also prepared identically. These samples were analyzed on a Shimadzu 9030 Q-ToF instrument in negative mode with a water/acetonitrile/ammonium acetate (pH 6.5) solvent system equipped with a C8 column using a DUIS source. Data analysis was performed using MZmine2 and homemade MATLAB scripts for Gaussian scoring functions to score for retention time overlap, signal intensity overlap, and anticipated mass overlap for mono-, di-, and tri-Marfey's adduct mass differences (2x1.0034, 4x1.0034, and 6x1.0034). Finally, this approach was also applied to mid-log phase MRSA extracts to identify amines and amino acids.

HRMS/MS-based approach for separation and quantification of amino acids by chemical isotope-labeled Marfey’s reagent

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.