UPLC-MS/MS Amino Acid Quantification

Ten microliter of reconstituted extract was transferred to an autosampler vial and was combined with 70 μL of Borate Buffer (Waters, 186003836) from Waters AccQ-Tag Derivatization Kit (target pH: 8–10) and vortexed. Twenty microliter of AccQ-Tag Derivatization Agent (Waters, 186003836) was added, vortexed and let stand for 1 min. Samples were derivatized (55°C, 10 min) and vortexed. Derivatized samples were quantified with a Waters Acquity UPLC, Xevo-μ Tandem Mass Spectrometer and an AccQ-Tag Ultra RP Column 130 Å, 1.7 μm, 2.1 mm, 100 mm column using multiple reaction monitoring (MRM) and internal standard calibration (72 (link), 73 (link)).