Wide-Scope Screening of Illegal Adulterants in Dietary and Herbal Supplements via Rapid Polarity-Switching and Multistage Accurate Mass Confirmation Using an LC-IT/TOF Hybrid Instrument

J Agric Food Chem. 2015 Aug 12;63(31):6954-67. doi: 10.1021/acs.jafc.5b02222. Epub 2015 Jul 31.

Abstract

A new analytical strategy was developed that integrates a generic sample preparation into a liquid chromatography-multistage ion trap/time-of-flight mass spectrometry (LC-IT(MS(n))/TOF), allowing for large-scale screening and qualitative confirmation of wide-scope illegal adulterants in different food matrices. Samples were pretreated by a fast single-tube multifunction extraction for accurate multistage mass measurement on the hybrid LC-IT/TOF system. A qualitative validation performed for over 500 analyte-matrix pairs showed the method can reduce most of the matrix effects and achieve a lower limit of confirmation at 0.1 mg/kg for 73% of the target compounds. A unique combination of dual-polarity detection, retention time, isotopic profile, and accurate MS(n) spectra enables more comprehensive and precise confirmation, based on the multiparameter matching by automated library searching against the user-created database. Finally, the applicability of this LC-IT(MS(n))/TOF-based screening procedure for discriminating coeluting isobars, identifying nontarget adulterants, and even tentatively elucidating unexpected species in real samples is demonstrated.

Keywords: accurate multistage mass spectrum; dietary supplements; hybrid ion trap/time-of-flight mass spectrometry; illegal adulterants; polarity-switching; qualitative screening; single-tube extraction.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, Liquid / methods*
  • Dietary Supplements / analysis*
  • Drug Contamination / legislation & jurisprudence
  • Drug Contamination / prevention & control*
  • Herbal Medicine
  • Tandem Mass Spectrometry / methods*