Abstract:
Rapid screening and quantitative determination of 82 pesticides with QuEChERS were achieved by ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In the orthogonal experiments, 9 combinations were designed to investigate the effect of 4 different adsorbents (PSA, C
18, GCB and SiO
2) on the purification performance of
Viola yedoensis Makino.
V. yedoensis samples were pretreated by PSA 800 mg, C
18 3 200 mg, GCB 1 600 mg and SiO
2 1 600 mg. The chromatographic separation of 82 pesticides was achieved by phenmenex DOD-4475-AN C
18 column using acetonitrile/water (0.1% formic acid and 10 mmol/L ammonium formate) in the gradient elution mode. Standard curve method was utilized for the quantitation. The results indicated that 82 pesticides showed good linear relationship within the corresponding concentration ranges (
r≥0.99). The detection limits (LOD) were 0.3-5 μg/kg and the limits of quantitation (LOQ) were 1-20 μg/kg. Under spiked levels of 0.02, 0.05 and 0.1 mg/kg, the average recoveries of most pesticides were between 70%-111%, and the relative standard deviations (RSD,
n = 6) were less than 19%. This method is simple, accurate and efficient, which can meet the requirements for the detection of 82 pesticide residues in
V. yedoensis samples.