Multiresidue LC-MS/MS Determination of 52 Non-Gas Chromatography-Amenable Pesticides and Metabolites in Fruits and Vegetables

This multi-residue pesticide sample preparation shows the steps used to process fruit and vegetable samples, extract and concentrate the extract by an Oasis HLB SPE method.

This multi-residue pesticide sample preparation shows the steps used to process fruit and vegetable samples, extract and concentrate the extract by an Oasis HLB SPE method.

Pre-treatment

1. Samples (lemon, raisin, tomato and avocado) were cut into small pieces.
   
2. A 20 g portion of homogenized sample was mixed with 60 mL 0.1% formic acid in methanol:water (80:20, v/v).
   
3. Extraction for 2 minutes with Ultra-Turrax at 8000 rpm.
   
4. Filtration and dilution with methanol:water 0.1% formic acid (80:20, v/v) to a final volume of 100 mL.
   
5. 2.5 mL aliquot diluted to 20 ml with 0.1% formic acid in water. Load 5 mL of the diluted extract onto the SPE Cartridge.

1. Journal of Chromatography A, 1109 (2006) 242-252.