Abstract: A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the determination of perchlorate, chlorate and bromate in vegetables and fruits. The type and amount of sorbents including primary secondary amine (PSA), graphitized carbon black (GCB) and C18, were optimized based on the recoveries. Samples were extracted twice with 50% acetonitrile/water. The extract was purified with a mixture of 40 mg of GCB and 200 mg of C18, separated on an IC-PakTM Anion HR column, and detected by UPLC-MS/MS. The matrix-matched external standard method was used for quantitation. Good linearity was achieved for the analytes in the concentration range of 0.5–100 mg/L with correlation coefficients all greater than 0.99. The average recoveries for all the compounds at spiked concentration levels of 5.0, 20.0 and 50.0 μg/kg ranged from 80.3% to 110.1%, with relative standard deviations (RSDs) from 2.1% to 9.6%. The limits of detection (LODs) and the limits of quantification (LOQs) were 0.5–1.5 mg/kg and 2.0–5.0 mg/kg, respectively. The developed method proved to be rapid, convenient, sensitive, accurate, stable, and suitable for simultaneous determination of perchlorate, chlorate and bromate in vegetables and fruits.

Key words: QuEChERS, perchlorate, chlorate, bromate, ultra-high performance liquid chromatography-tandem mass spectrometry