title: N-methylimidazolium ionic liquid-functionalized silica as a sorbent for selective solid-phase extraction of 12 sulfonylurea herbicides in environmental water and soil samples.
abstract: A novel material for solid-phase extraction (SPE) was synthesized by chemical immobilization of a functionalized N-methylimidazolium ionic liquid on silica gel. Cartridges packed with the synthetic material were successfully applied to the pre-concentration of trace-level thifensulfuron-methyl, metsulfuron-methyl, chlorsulfuron, sulfometuron-methyl, rimsulfuron, ethametsulfuron, tribenuron-methyl, bensulfuron-methyl, prosulfuron, pyrazosulfuron, chlorimuron-ethyl and primisulfuron from environmental water and soil samples. The 12 sulfonylurea herbicides (SUs) obtained a good resolution in less than 50 min using HPLC with a UV detector. The recovery studies using the ionic liquid-functionalized silica as a sorbent were performed by three consecutive extractions of water and soil samples at two spiked levels. The average recovery for each analyte was in the range of 53.8-118.2% for the water samples and 60.9-121.3% for the soil sample, with RSDs lower than 11.3% in all cases. The ionic liquid-functionalized silica cartridges showed higher selectivity for the SUs than commercially available C(18) cartridges did.
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China.
authors.forename: Guozhen
authors.initials: G
authors.lastname: Fang
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Junping
authors.initials: J
authors.lastname: Wang
authors.forename: Jinxing
authors.initials: J
authors.lastname: He
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D006540:Herbicides / Q000032:analysis*; D012117:Resins, Synthetic / Q000737:chemistry; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D052616:Solid Phase Extraction / Q000295:instrumentation* / Q000379:methods*; D013453:Sulfonylurea Compounds / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D006540:Herbicides; D012117:Resins, Synthetic; D012989:Soil Pollutants; D013453:Sulfonylurea Compounds; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide