In-situ ionic liquid dispersive liquid-liquid microextraction using a new anion-exchange reagent combined FeO magnetic nanoparticles for determination of pyrethroid pesticides in water samples.

In this work, in-situ ionic liquid dispersive liquid-liquid microextraction combined ultrasmall FeO magnetic nanoparticles was developed as a kind of pretreatment method to detect pyrethroid pesticides in water samples. New anion-exchange reagents including Na[DDTC] and Na[N(CN)] were optimized for in-situ extraction pyrethroids, which showed enhanced microextraction performance. Pyrethroids were enriched by hydrophilic ionic liquid [P][Br] (aqueous solution, 200 μL, 0.2 mmol mL) reaction in-situ with anion-exchange reagent Na[N(CN)] (aqueous solution, 300 μL, 0.2 mmol mL) forming hydrophobic ionic liquid as extraction agent in water sample (10 mL). Ultrasmall superparamagnetic iron oxide nanoparticles (30 mg) were used to collect the mixture of ionic liquid and pyrethroids followed by elution with acetonitrile. The extraction of ionic liquid strategies was unique and efficiently fulfilled with high enrichment factors (176-213) and good recoveries (80.20-117.31%). The method was successively applied to the determination of pyrethroid pesticides in different kinds of water samples with the limits of detection ranged from 0.16 to 0.21 μg L. The proposed method is actually nanometer-level microextraction (average size 80 nm) with the advantages of simplicity, rapidity, and sensitivity.