SOLID-MATRIX PARTITION FOR SEPARATION OF ORGANOCHLORINE PESTICIDE-RESIDUES FROM FATTY MATERIALS

A fast, single-step and efficient partition between n-hexane and acetonitrile on ready-to-use, disposable cartridges of Kieselghur-type material has been developed for the separation of organochlorine (OC) pesticide residues from oils and fats. The extract is cleaned up with Florisil minicolumn chromatography, followed by a solid-matrix sulphuric acid treatment. Carry-over of lipid material through the partition step is lower compared to conventional, separatory-funnel partition. Recovery of eighteen OC pesticides from 1.0 g olive oil was between 72% and 104% at spiking levels between 0.01 and 0.15 mg/kg for the different compounds.