Direct analysis of isopropylthioxanthone (ITX) in milk by high-performance liquid chromatography/tandem mass spectrometry

Renzo Bagnati, Giancarlo Bianchi, Elena Marangon, Ettore Zuccato, Roberto Fanelli, Enrico Davoli

Research output: Contribution to journalArticle


A fast screening method is presented for detecting isopropylthioxanthone (ITX) contamination in milk. The method is based on direct high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) analysis of milk samples. Sample preparation is limited to the addition of a deuterated ITX solution in acetonitrile that serves both as internal standard and to precipitate proteins. The method is highly accurate and sensitive. Isomeric specific analyses of 2-ITX and 4-ITX are possible at 6 μg/L levels with about 5% precision and accuracy. This approach has been used to check contamination in samples like milk, soy milk, baby milk, in their packaging material. Out of 37 milk samples analyzed, 16 were positive with concentrations ranging from 173-439 μg/L for 2-ITX and from

Original languageEnglish
Pages (from-to)1998-2002
Number of pages5
JournalRapid Communications in Mass Spectrometry
Issue number13
Publication statusPublished - 2007


ASJC Scopus subject areas

  • Analytical Chemistry
  • Spectroscopy

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