Pesticide and Metabolite Residues

Analysis of pesticide levels in food and beverage products is important not only to insure low levels for human consumption, but also to avoid international trade problems. At the present time, more than 1000 pesticide and metabolite residue compounds are identified as associated with food crops, either in current use, or used in the past. Several techniques are commonly used:
  • Extraction/Cleanup using QuEChERS (pronounced ′catchers′): The Quick, Easy, Cheap, Effective, Rugged, Safe sample preparation approach developed by Anastassiades and Lehotay simplifies the sample preparation of pesticides from foods of plant origin. This dispersive SPE method uses bulk materials instead of traditional tube-based hardware. Extraction is done using a solvent (such as acetonitrile) and pre-weighed extraction/buffer salts. After a centrifugation step, the extract is cleaned with bulk sorbents. Several materials are available as QuEChERS cleanup sorbents, each effective for the removal of specific interferences, and can be used individually or in combinations best suited to the sample matrix.
  • Extraction/Cleanup using Traditional SPE: Traditional SPE can also be employed for the cleanup of samples prior to analysis. Our Supelclean offering includes tubes with a single sorbent, and also tubes with multiple sorbents. An SPE tube with a multi-layer design allows all cleanups to be accomplished in a single step.
  • HPLC Analysis: LC-MS/MS is able to quickly achieve proper identification and low detection limits for large analyte lists. It is critical to use high quality columns, solvents, and mobile phase buffers to minimize artifacts which will interfere with the sensitivity of the instrumentation.
  • GC Analysis: GC-MS is also used as an analytical technique, requiring columns with low bleed and high inertness characteristics.

Technical Article:
′Positive List′ Chemicals by GC-MS on the SLB-5ms
Analysis of Organophosphorous Pesticides in Produce by Solid/Liquid Extraction and Dual-Layer Amino-Silica/Carbon SPE Cleanup and GC-NPD
Recovery & Sample Cleanup of Pesticides in Spinach Using Supelclean ENVI-Carb II/PSA SPE
Analysis of Melamine in Milk
Melamine and Related Compounds in Dog Food Using GC-MS
Improved Recovery of the Fungicide Carbendazim from Various Orange Juice Matrices by Employing QuEChERS Cleanup