Variables: concentration Keywords: high resolution mass spectrometry Substances: 1-Propanesulfonate (KCXFHTAICRTXLI-UHFFFAOYSA-N) 1-Methyl-Benzotriazole (HXQHRUJXQJEGER-UHFFFAOYSA-N) 1-Naphthylacetic acid (PRPINYUDVPFIRX-UHFFFAOYSA-N)