Fig. 3.
MRM signal intensities obtained for different mobile phase compositions: solvent 1 and 3, ion currents for transition derivatized precursor ion/fragment ion; solvent 2 and 4, ion currents for transition methylamine adduct of derivatized precursor ion/fragment ion. (Solvent 1: A, 0.1% formic acid in H2O and B, 0.1% formic acid in methanol. Solvent 2: A, 0.1% formic acid, 5 mM methylamine in H2O, and B, 0.1% formic acid in methanol. Solvent 3: A, 10 mM ammonium formate in H2O and B, 0.1% formic acid in methanol. Solvent 4: A, 10 mM ammonium formate, 5 mM methylamine in H2O, and B, 0.1% formic acid in methanol)