title: The determination of organochlorine pesticides based on dynamic microwave-assisted extraction coupled with on-line solid-phase extraction of high-performance liquid chromatography.
abstract: A rapid technique based on dynamic microwave-assisted extraction coupled with on-line solid-phase extraction of high-performance liquid chromatography (DMAE-SPE-HPLC) has been developed. A TM(010) microwave resonance cavity built in the laboratory was applied to concentrate the microwave energy. The sample placed in the zone of microwave irradiation was extracted with 95% acetonitrile (ACN) aqueous solution which was driven by a peristaltic pump at a flow rate of 1.0 mL min(-1). The extraction can be completed in a recirculating system in 10 min. When a number of extraction cycles were completed, the extract (1 mL) was diluted on-line with water. Then the extract was loaded into an SPE column where the analytes were retained while the unretained matrix components were washed away. Subsequently, the analytes were automatically transferred from the SPE column to the analytical column and determined by UV detector at 238 nm. The technique was used for determination of organochlorine pesticides (OCPs) in grains, including wheat, rice, corn and bean. The limits of detection of OCPs are in the range of 19-37 ng g(-1). The recoveries obtained by analyzing the four spiked grain samples are in the range of 86-105%, whereas the relative standard deviation (R.S.D.) values are <8.7% ranging from 1.2 to 8.7%. Our method was demonstrated to be fast, accurate, and precise. In addition, only small quantities of solvent and sample were required.
authors.affiliation: College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
authors.forename: Ligang
authors.initials: L
authors.lastname: Chen
authors.forename: Lan
authors.initials: L
authors.lastname: Ding
authors.forename: Haiyan
authors.initials: H
authors.lastname: Jin
authors.forename: Daqian
authors.initials: D
authors.lastname: Song
authors.forename: Huarong
authors.initials: H
authors.lastname: Zhang
authors.forename: Jiantao
authors.initials: J
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Zhang
authors.forename: Yutang
authors.initials: Y
authors.lastname: Wang
authors.forename: Hanqi
authors.initials: H
authors.lastname: Zhang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D008872:Microwaves; D010575:Pesticides / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D006843:Hydrocarbons, Chlorinated; D010575:Pesticides