Paper spray ionization mass spectrometry applied for quantification of pesticides and discrimination from tomato varieties (Solanum lycopersicum)

Abstract

The determination of pesticide residues in tomatoes is usually performed by GC–MS and LC–MS, which provide high analytical performance but require several steps of sample preparation. Thus, this work employed a simpler and faster technique, the Paper Spray Ionization Mass Spectrometry (PSI-MS), combined with Principal Component Analysis (PCA) to differentiate the tomatoes varieties and for quantification of pesticides residues. It was determined a metabolic profiling by PSI-MS and the samples were grouped according to the variety using PCA. A quantitative method was developed for sensitive and accurate quantitative analysis of the fungicide cyazofamid by PSI(+)-MS using fruit peels of two varieties of tomatoes. The method showed a calibration curve with R2> 0.99, and low limits of detection (LOD) and quantification (LOQ) of 10 ng.mL−1 and 25 ng.mL−1, respectively. The intra-day and inter-day recoveries percentage were in a range of 93.87–109.32 % and 99.54–100.81 % for variety Sweet Heaven, respectively. Similar results were obtained for variety BS II0012 with a satisfactory average recovery ranged from 89 % to 108 %, within the standards established by the regulatory agency. The results obtained reinforce the potential of PSI-MS as a rapid and simple analytical tool for determination of pesticide residue in agricultural products.