title: Dispersive solid-phase extraction followed by vortex-assisted dispersive liquid-liquid microextraction based on the solidification of a floating organic droplet for the determination of benzoylurea insecticides in soil and sewage sludge.
abstract: A novel dispersive solid-phase extraction combined with vortex-assisted dispersive liquid-liquid microextraction based on solidification of floating organic droplet was developed for the determination of eight benzoylurea insecticides in soil and sewage sludge samples before high-performance liquid chromatography with ultraviolet detection. The analytes were first extracted from the soil and sludge samples into acetone under optimized pretreatment conditions. Clean-up of the extract was conducted by dispersive solid-phase extraction using activated carbon as the sorbent. The vortex-assisted dispersive liquid-liquid microextraction based on solidification of floating organic droplet procedure was performed by using 1-undecanol with lower density than water as the extraction solvent, and the acetone contained in the solution also acted as dispersive solvent. Under the optimum conditions, the linearity of the method was in the range 2-500 ng/g with correlation coefficients (r) of 0.9993-0.9999. The limits of detection were in the range of 0.08-0.56 ng/g. The relative standard deviations varied from 2.16 to 6.26% (n = 5). The enrichment factors ranged from 104 to 118. The extraction recoveries ranged from 81.05 to 97.82% for all of the analytes. The good performance has demonstrated that the proposed methodology has a strong potential for application in the multiresidue analysis of complex matrices.
authors.affiliation: Key Laboratory of Eco-Environment of Three Gorges Region of Ministry of Education, Chongqing University, Chongqing, China.|Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Tsinghua University, Beijing, China.
authors.forename: Guilong
authors.initials: G
authors.lastname: Peng
authors.affiliation: Key Laboratory of Eco-Environment of Three Gorges Region of Ministry of Education, Chongqing University, Chongqing, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: He
authors.affiliation: Key Laboratory of Eco-Environment of Three Gorges Region of Ministry of Education, Chongqing University, Chongqing, China.
authors.forename: Daniel
authors.initials: D
authors.lastname: Mmereki
authors.affiliation: Mathematics and Physics, Armed Police College, Chengdu, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Tsinghua University, Beijing, China.|The First Clinical Medical College of Fujian Medical University, Fuzhou, China.|Department of Orthopaedics, Fujian Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou, China.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Zhong
authors.affiliation: Department of Chemistry, Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Tsinghua University, Beijing, China.
authors.forename: Hanyang
authors.initials: H
authors.lastname: Liu
authors.affiliation: School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing, China.
authors.forename: Weiliang
authors.initials: W
authors.lastname: Pan
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhou
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis (Southwest University), Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, China.
authors.forename: Junhua
authors.initials: J
authors.lastname: Chen
keywords: Activated carbon; Benzoylurea insecticides; Dispersive liquid-liquid microextraction; Dispersive solid-phase extraction; Vortex-assisted extraction