Development of a design of experiments (DOE) assistant modified QuEChERS method coupled with HPLC-MS/MS simultaneous determination of twelve lipid-soluble pesticides and four metabolites in chicken liver and pork

A modified QuEChERS method combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the determination of twelve lipid-soluble pesticides and four metabolites in chicken liver and pork. The QuEChERS method was optimized using two models, Plackett-Burman design and Central Composite Face-centered design, which enhanced its science and accuracy, making the optimization process more efficient and precise. Under optimal conditions, all coefficients of determination were > 0.9916. Limits of detection and limits of quantitation were 0.4-3.0 mu g/kg and 1.0-10.0 mu g/kg, respectively. In chicken liver, the recoveries (except for haloxyfop, haloxyfop-methyl, haloxyfop-etotyl, clodinafop-propargyl, and clodinafop) were 75.7-109.3% with relative standard deviations (RSDs) of 0.6-9.8%. In pork, the recoveries (except for difluorenican) were 73.4-104.7% with RSDs of 1.1-9.9%. Abnormal recoveries observed in this study could be attributed to the presence of esterase in chicken liver and pork. In addition, the method has been successfully applied to the detection of real samples. This study not only provides valuable data support for establishing maximum residue limits of target pesticides in chicken livers and pork, but also contributes an efficient and reliable detection tool for the animal-derived food safety monitoring system.