Optimisation of extraction methods and quantification of benzo[a]pyrene and benz[a]anthracene in yerba maté tea by isotope dilution mass spectrometry.

A gas chromatography-isotope dilution mass spectrometry (GC-IDMS) technique was developed for the quantification of two heavy polyaromatic hydrocarbons (PAHs), benz[a]anthracene and benzo[a]pyrene, in yerba maté tea (maté). The optimisation of two extraction methods, namely liquid-liquid extraction and accelerated solvent extraction, was carried out. Both optimised methods were validated using a certified reference material of fine dust and the results were within the expanded uncertainties at 95% confidence level.

Determination of cyanuric acid using exact matching isotope dilution mass spectrometry.

A high-accuracy double isotope dilution mass spectrometric method using an exact matching approach with GC coupled to a mass spectrometer for the analysis of cyanuric acid in fortified milk powder was developed. Various parameters for sample clean-up such as the type of SPE cartridge, GC column and type of derivatizing agent used were investigated. The method was found to be linear in the concentration range of 0.