Determination of 21 organochlorine pesticides in tree leaves using solid-phase extraction clean-up cartridges.

Determination of 21 organochlorine pesticides in tree leaves using solid-phase extraction clean-up cartridges.

Journal of chromatography. A (2005-01-12)

M Barriada-Pereira, M J González-Castro, S Muniategui-Lorenzo, P López-Mahía, D Prada-Rodríguez, E Fernández-Fernández

ABSTRACT

A method to determine 21 organochlorine pesticides (OCPs) in tree leaves [chestnut (Castanea sativa), hazel (Corylus avellana), oak (Quercus robur) and walnut tree (Juglans regia)] based on microwave-assisted extraction (MAE) followed by solid-phase extraction (SPE) clean-up is described. After extraction with hexane:acetone (50:50), four different sorbents (Florisil, tandem Florisil + alumina, silica and ENVI-Carb) were assayed for the clean-up step. Pesticides were eluted with 5 mL of hexane:ethyl acetate (80:20) and determined by gas chromatography and electron capture detection (GC-ECD). Carbon was the sorbent, which provided colourless eluates and chromatograms with less interferent compounds. Analytical recoveries obtained were ca. 100% for all the studied pesticides with this sorbent.

MATERIALS

Product Number

Brand

Product Description

55474-U

Supelco

Supel^™ QuE, PSA/C18/ENVI-Carb Tube, pk of 50, AOAC^® 2007.01, centrifuge tube volume 15 mL , Shaker Compatible

55446-U

Supelco

Supel^™ QuE, PSA/ENVI-Carb Tube 1, pk of 50, suitable for EN 15662:2008 per BS, centrifuge tube volume 15 mL , Shaker Compatible

55464-U

Supelco

Supel^™ QuE, PSA/ENVI-Carb Tube 2, pk of 50, suitable for EN 15662:2008 per BS, centrifuge tube volume 15 mL , Shaker Compatible