An effective method for pesticide residues determination in tobacco by GC-MS/MS and UHPLC-MS/MS employing acetonitrile extraction with low-temperature precipitation and d-SPE clean-up

• Citrate QuEChERS with cold MeCN allowed an efficient extraction of 55 pesticides from tobacco.
• Low temperature precipitation and d-SPE were essential to obtain a clean extract.
• GC-MS/MS and UHPLC-MS/MS analyses provided satisfactory selectivity and sensitivity.
• The compounds showed method LOQ values between 25 and 75 µg kg−1.

An effective method has been developed and validated for the determination of residues of 55 pesticides in tobacco. The proposed sample preparation method is based on acetonitrile extraction, low-temperature precipitation (LTP) and dispersive solid phase extraction (d-SPE) clean-up. Gas chromatography and ultra-high performance liquid chromatography analysis, both coupled to tandem mass spectrometry (GC-MS/MS and UHPLC-MS/MS), were used for determination. LTP is easy to perform and was crucial to obtain a clean extract. Method quantification limit for the pesticides were between 25 and 75 µg kg−1. Extraction recoveries obtained for blank samples spiked at 25, 75, 125 and 250 µg kg−1 levels ranged from 63 to 161% with relative standard deviations (RSD)≤20%. The method was successfully applied to the analysis of thirteen different tobacco samples, providing to be a robust procedure for routine analysis. The compounds pirimiphos methyl and isofenphos presented residues in the range of 35–51 µg kg−1.

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