Multi-mycotoxins analysis in Pheretima using ultra-high-performance liquid chromatography tandem mass spectrometry based on a modified QuEChERS method.

A sensitive and high-throughput method was established and validated for the simultaneous determination of 22 mycotoxins in Pheretima aspergillum (E.Perrier) and Pheretima guillelmi (Michaelsen). A modified Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method was used for sample preparation with recoveries ranging from 73% to 105% with relative standard deviations (RSDs) <8.0% for all target analytes. Ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-MS/MS) was applied for separation and detection in ESI (+) and ESI (-) modes with the limits of detection (LOD) in the range of 0.05-10μgkg(-1). The 22 compounds could be accurately quantified in the 0.5-1000μgkg(-1) concentration range with correlation coefficients >0.99. In all cases, the intra- and inter-day precisions were lower than 6% and 10%, respectively. Matrix-matched calibration was utilized for quantification purposes to compensate for the matrix effects. Furthermore, the established method was successfully applied in 17 batches of normal real samples collected from different areas of China and 2 batches of moldy samples due to improper storage, only mold-contaminated samples were confirmed to have fumonisin B1 (FB1) and fumonisin B2 (FB2) contamination at 2.54-3.78μgkg(-1). The constructed method could serve as a practical application of the UHPLC-MS/MS method for the trace analysis of multiple mycotoxins in complex matrixes, especially for those with high lipid contents.