title: Dynamic microwave-assisted extraction combined with continuous-flow microextraction for determination of pesticides in vegetables.
abstract: A simple, rapid, solventless and cost-effective dynamic microwave-assisted extraction (DMAE) combined with continuous-flow microextraction (CFME) system was firstly assembled and validated for extraction of eight organophosphorus pesticides in vegetables. The method combines the advantages of DMAE and CFME, and extends the application of the single drop microextraction to complex solid samples. The extraction, separation, and enrichment were performed in a single step, which could greatly simplify the operation and reduce the whole pretreatment time. In the developed method, analytes were first extracted from the vegetables using 3% NaCl solution as extraction solvent, then concentrated into microextraction solvent. After extraction, the microextraction solvent containing the enriched analyte was directly analyzed by GC-MS without any filtration or clean-up process. Several parameters affecting the extraction efficiency were investigated and optimized. Real vegetable samples were analyzed, satisfactory recoveries were obtained in the range of 80.7-106.7%, and relative standard deviations were lower than 8.7%.
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Lijie
authors: L
authors: Wu
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Mingzhu
authors: M
authors: Hu
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Zhanchao
authors: Z
authors: Li
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Ying
authors: Y
authors: Song
authors: School of Chemical and Materials Engineering, Yanching Institute of Technology, Langfang 065201, China.
authors: Cui
authors: C
authors: Yu
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Hanqi
authors: H
authors: Zhang
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors: Aimin
authors: A
authors: Yu
authors: Chinese Academy of Inspection and Quarantine, Beijing 100123, China.
authors: Qiang
authors: Q
authors: Ma
authors: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China. Electronic address: wangziming@jlu.edu.cn.
authors: Ziming
authors: Z
authors: Wang
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D008872:Microwaves; D010575:Pesticides / Q000032:analysis / Q000737:chemistry*; D014675:Vegetables / Q000737:chemistry*
chemical_list: D010575:Pesticides
keywords: Continuous-flow microextraction; Dynamic microwave-assisted extraction; Fresh vegetables; Gas chromatography mass spectrometry; Organophosphorus pesticides