Aqueous biphasic system(ABS) based on the surfactant(triton x-100

Tr) and cholinium ionic liquids were developed for the extraction of triazine herbicides in honey samples.The influences of phase compositions and temperature on the formation of ABS were investigated.The biphasic region of ABS decreased with the increase of carbon chains of the anions in ionic liquids

but made no distinct difference with the increase of temperature.The partitioning behaviors of the selected herbicides were investigated using the Tr-choline acetate(［Ch］［Ac］)ABS.Results showed that the analytes were mainly concentrated in the surfactant-rich phase.The partition coefficients of the herbicides decreased with the increase of Tr mass fractions

while increased with the increase of ［Ch］［Ac］concentrations

which indicated that the salting-out ability of the ionic liquid played an important role in the system formation.Under the optimized conditions

there were good linear relationships for the selected herbicides over the concentration range of 0.1-20.0 mg/L with correlation coefficients(r2) not less than 0.992.The limits of quantitation for the analytes ranged from 0.005 mg/kg to 0.02 mg/kg

and the average recoveries were between 75.0% and 114% with RSDs of 5.2%-76%.The proposed method is suitable for the determination of the target herbicides in honey samples.