Rapid single-step cleanup method for analyzing 47 pesticide residues in pepper, chili peppers and its sauce product by high performance liquid and gas chromatography-tandem mass spectrometry

A novel rapid single-step cleanup method combined with quick, easy, effective, rugged, and safe (QuEChERS) extraction approach for determining multi-pesticide residues was developed. For the single-step QuEChERS (sin-QuEChERS) cleanup procedure, a specified cartridge was fitted within an extraction centrifuge tube for removing non-target substances. Multi-walled carbon nanotubes (MWCNTs) and Primary Secondary Amine (PSA) mixed with salts functioned as absorbents. Method validation was applied on 47 representative pesticides in pepper, chili peppers and chili sauce by LC-MS/MS and GC-MS/MS detection. Compared to the original QuEChERS method, the Sin-QuEChERS method was fast and convenient without any further vortex or centrifugation. Satisfactory recoveries of most pesticides at two concentration levels were in the range of 70-120% (except for pyrimethanil) with relative standard deviations (RSDs n = 5) lower than 17%. The limit of quantification (LOQs) for the 47 pesticides were 0.01 mg/kg in three matrices. Sin-QuEChERS method was successfully applied to monitor the market multi-residues.