Development and Validation of New Clean-Up Approach for 21 OrganoChlorinated Pesticides (OCPs)

Abstract

A validated procedure was developed for the separation and clean-up of Organo-Chlorinated
Pesticides (OCPs) extracted from fish samples, using different adsorbent materials and different
solvents composition. Pressurized liquid extraction (PLE) has been utilized for the extraction of OCPs.
PLE provides one of the best alternative to conventional extraction methods. The different adsorbent
materials as well as solvents composition were evaluated for the best clean-up steps of OCPs extracted
from fish samples. Among the eight examined adsorbent materials, florisil and alumina were selected
with hexane: ethylacetate (8:2, v/v) solvent mixture throughout the experiment. The highest recoveries
were obtained (75-99.8 %). Detection was performed by GC-MS in Negative Chemical Ionization
(NCI) mode, due to its high sensitivity and selectivity to chlorinated compounds. Bio-Beads SX-3
Based on Gel permeation Chromatography (GPC) was utilized for the removal of fat. The accuracy of
the method (n= 5) is expressed as recovery (%) that was calculated to be between 56% and 98%, and
the precision of the method is expressed as Relative Standard Deviation (RSD), that was obtained to
be between 5% and 28 %.