QuEChERS, the abbreviation of Quick, Easy, Cheap, Effective, Rugged and Safe, is a widely used and effective method because of the variety of pesticides and the detection samples. QuEchERS is widely used in the pretreatment of pesticide analysis due to its high recovery and accuracy, simple operation and low pollution for a large number of polar and volatile pesticides. It is simply summarized as the process of extraction, purification, and extraction.
The first step is the extraction.
Add 10 ml acetonitrile to the sample containing 10 g, and then add internal standard and shake it. Add 4 g MgSO4, 1 g NaCl, 1 g trisodium citrate hydrate, 0.5 g disodium citrate hydrate, shake it for 1 minute, then centrifuge the sample for 5 minutes at 3000 U/min.
The second step is purification.
One is the decentralized SPE purification process. Transfer 1 ml supernatant to the centrifugal tube containing 150 mg MgSO4 and 25 mg PSA, shake it for 30 seconds and then centrifuge for 5 minutes at 3000 U/min. Preserve it in acetonitrile solution containing 5% formic acid. And for GC/MS detection, it requires conversion solvents.
The other is the extraction column purification process. Elute the PSA and GCB double-layer composite columns with 5 ml toluene and transfer supernatant to the column. And then collect the solvent. Then elute with 6-12 ml 3:1 acetone: toluene solvent, and analyzed by GC/MS after concentration.
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