GC Determination of Residual Amounts of 3 Organophosphorus Pesticides in Fruits with Ionic Liquid-Liquid Phase Micro-extraction (IL-LPME)

Smashed fruit sample was extracted with CH3OH-H2O (10+90) ultrasonically, the supernatant was taken for IL-LPME treatment, to separate and enrich the 3 organophosphorus pecticides (OPP′s), namely malathion, chlorphrifos and parathion, which were determined by GC. The ionic liquid, 1-butyl-3-methylimidazole-hexafluoroborate was used as solvent for extraction. Enrichment multiples of IL-LPME were found to be 132, 119, 147 times higher than those without LPME for the 3 pesticidos respectively. HP-5 quartz capillary column was used in GC separation and flame photometric detection was adopted in the determination. Ranges of linearity for the 3 OPP′s were same between 1.00-20.0 mg·L-1, with values of detection limits (3S/N) of 0.4, 0.1, 0.2 mg·L-1 respectively. Using fruit samples as matrixes, values of recovery found by standard addition method were in the range of 96.5%-104.3% with RSD′s (n=5) less than 6%.