Abstract
The reaction of α‐ and β‐thujones with dansylhydrazine (DNSH) was studied using reversed phase liquid chromatography (LC) with fluorescence detection. The derivatization procedure, although slow, was applied for determination of α‐thujone in white vermouth at concentrations 0.45–4.5 µg/L using a C18 solid phase extraction column for cleanup; recoveries of added α‐thujone were in the range 60–77%. Separation of dansyl α‐ and β‐thujones was achieved by LC and their identity confirmed by LC‐tandem mass spectrometry (MS/MS).