Sensitive Determination of Quinones by High-Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry with Methanol Derivatization

Quinones are a class of compounds having substantial toxicity and pharmacological function. This work has produced a derivatization method for quinone detection with high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS). Through introducing tags (methoxy) to the quinone structures, the ionization efficiencies of five quinones (p-benzoquinone (BQ), methyl-p-benzoquinone (MBQ), 1,4-naphthoquinone (1,4-NQ), 1,2-naphthoquinone (1,2-NQ), and 1,4-anthraquinones (AQ)) were greatly improved during ESI. The limit of detections (LODs) for quinone determination could be flexibly adjusted by changing the reaction time or the solvent composition. While lower LODs (<0.02 - 2.06 pg for five quinones) were achieved with methanol as the derivatization reagent, the reaction time was substantially shortened (from 27 to 3 h or 11 h) with methanol/water (v/v, 1:1) as the derivatization reagent. Finally, the proposed method was successfully used for quinone determination in airborne particulates.