Enhanced ion sampling efficiency allows sample dilution in order to minimize matrix effects for multi-residue pesticide analysis in black tea

摘要

Challenges in multi-residue pesticide analysis include the diversity of pesticide compound classes found in food analysis, matrix complexity, low concentration and poor ionization efficiency of some pesticides. In this work we evaluate the use of dilution as a means of minimizing matrix effects and achieving rugged and high performance quantitation at trace levels in black tea using UHPLC-triple quadrupole mass spectrometry and dynamic MRM with fast polarity switching. Black tea was selected as test matrix due to its high complexity. Increased ion sampling efficiency achieved using dual ion funnel technology allowed a 20-fold sample dilution while still achieving the maximum residue level (MRL) stipulated by the European Union.