Direct tandem mass spectrometric analysis of amino acids in plasma using fluorous derivatization and monolithic solid-phase purification

• Published in: Journal of pharmaceutical and biomedical analysis Vol. 115; pp. 201 - 207
• Main Authors: Tamashima, Erina, Hayama, Tadashi, Yoshida, Hideyuki, Imakyure, Osamu, Yamaguchi, Masatoshi, Nohta, Hitoshi
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 10-11-2015
• Subjects: Amino acids; Amino Acids - blood; Animals; Direct tandem mass spectrometric analysis; Disease Models, Animal; Fatty Acids - chemistry; Fluorocarbons - chemistry; Fluorous derivatization; Humans; Maple Syrup Urine Disease - blood; Mice; Mice, Mutant Strains; Monolithic fluorous solid-phase extraction; Phenylalanine Hydroxylase - genetics; Phenylketonurias - blood; Reproducibility of Results; Solid Phase Extraction - methods; Spectrometry, Mass, Electrospray Ionization - methods; Tandem Mass Spectrometry - methods; Monolithic fluorous solid-phase extraction; Amino acids; Direct tandem mass spectrometric analysis; Fluorous derivatization
• ISSN: 0731-7085; 1873-264X
• DOI: 10.1016/j.jpba.2015.07.008

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•A novel tandem mass spectrometric analysis method for amino acids was developed.•Amino acids were derivatized with a fluorous aldehyde by reductive amination.•The derivatives were purified with a fluorous solid phase extraction spin column.•Amino acids in plasma were determined rapidly without matrix interference.•The method was applied to plasma samples from metabolic disorder model mice.
In this study, we developed a novel direct tandem mass spectrometric method for rapid and accurate analysis of amino acids utilizing a fluorous derivatization and purification technique. Amino acids were perfluoroalkylated with 2H,2H,3H,3H-perfluoroundecan-1-al in the presence of 2-picoline borane via reductive amination. The derivatives were purified by perfluoroalkyl-modified silica-based monolithic solid-phase extraction (monolithic F-SPE), and directly analyzed by tandem mass spectrometry using electrospray ionization without liquid chromatographic separation. The perfluoroalkyl derivatives could be sufficiently distinguished from non-fluorous compounds, i.e. the biological matrix, due to their fluorous interaction. Thus, rapid and accurate determination of amino acids was accomplished. The method was validated with human plasma samples and applied to the analysis of amino acids in the plasma of mice with maple syrup urine disease or phenylketonuria.