Dispersive solid phase extraction (DSPE), commonly referred to as “QuEChERS”, is a fast, simple, inexpensive, effective, durable, and safe method for sample preparation. This method uses bulk solid phase extraction sorbent to extract and purify food. Samples such as agricultural products are used for pesticide residue analysis, and their operation is becoming more and more popular.
Using the QuEChERS method, food and agricultural product samples are first added to an extraction tube containing pre-precisely weighed high-content salts (such as sodium chloride and magnesium sulfate) and buffering reagents (such as citrate), salt and The buffering agent can promote the separation of the two phases and stabilize the pesticide which is easily changed by the acid and alkali, and then extract the water-soluble solvent (such as acetonitrile) into the extraction tube. After the extraction tube was oscillated and centrifuged, a part of the organic phase layer was taken out and added to a dispersed SPE (dSPE) purification tube for further processing. The extract is added to the purification tube, and the sample is dispensed or adsorbed between the extract and the bulk SPE filler to achieve purification of the matrix sample. This method is simple and fast. After the purified sample is shaken and centrifuged, the supernatant can be directly or simply processed and then passed to the next analysis.