Dispersive solid phase extraction (d-SPE) analysis is a simple and straightforward sample preparation technique suitable for a wide variety of food and agricultural products. One specific method which has become popular is the QuEChERS technique which was created to facilitate the rapid screening of large numbers of food and agricultural samples for pesticide residues. Waters DisQuE d-SPE products include conveniently-packaged centrifuge tubes and foil pouches containing pre-weighed sorbents and buffers for use with both the Association of Analytical Communities (AOAC) and European Committee for Standardization (CEN) QuEChERS methods. Waters QuEChERS kits make sample prep quick and easy for multi-residue analysis in food and agricultural products.
Compared to traditional sample preparation techniques, DisQuE solutions offer:
The Science Behind DisQuE
The QuEChERS procedure is based on an initial single-phase extraction using 10 g or 15 g sample with acetonitrile at 1 mL acetonitrile per 1 g of sample. A liquid-liquid partition is created by adding excess salts and buffers to the extract. After centrifugation, the acetonitrile layer containing the analytes of interest is collected. The sample matrix can be further cleaned and excess water removed with a single d-SPE step by mixing acetonitrile extract with anhydrous MgSO4 and primary secondary amine (PSA) sorbents. Additional sorbents such as C18 or graphitized carbon black (GCB) could be added as needed for specific matrix cleanup. The final extract can be analyzed directly by either GC-MS or LS-MS/MS with a simple dilution.
Waters DisQuE Dispersive Sample Preparation products include conveniently-packaged centrifuge tubes and foil pouches containing pre-weighed sorbents and buffers for use with both the AOAC (2007.01) and CEN (EN 15662) QuEChERS methods.
Improved Pesticide Analysis
QuEChERS methods were originally developed to extract pesticides from fruits and vegetables. Combining an initial salting out liquid-liquid extraction with d-SPE cleanup, these methods have been demonstrated to be very effective for multi-residue analysis of pesticides, veterinary drugs, and mycotoxins in a wide variety of food and agricultural products. Waters QuEChERS solutions offer numerous advantages over alternative pesticide analysis products and techniques:
Convenient DisQue QuEChERS formats and kits
Complete solutions and kitted methods add value to your laboratory function by addressing the need for simple protocols that require little training to implement. Extraction tubes and pouches, as well as the clean-up tubes, are available separately to support customized applications and greater flexibility. The clean-up tubes are available in the standard 2 mL size as well as a 15 mL size for sample enrichment.
Waters offers several sorbent blends to help remove complex matrix from your sample:
Waters offers kits which comply with both AOAC and CEN QuEChERS methods. Alternative sorbent blends to suit your laboratory’s needs may be purchased by special order.