title: Simultaneous determination of herbicide residues in tobacco using ultraperformance convergence chromatography coupled with solid-phase extraction.
abstract: A time-saving and organic solvent efficient method to simultaneously determine six kinds of herbicide residues in tobacco using solid-phase extraction for sample clean-up and preconcentration and the highly sensitive ultraperformance convergence chromatography method was developed. Parameters for ultraperformance convergence chromatography, including the choice of stationary phase and modifiers, autobackpressure regulator pressure, column temperature, and the flow rate of mobile solvents, were optimized. The herbicide residues of napropamide, alachlor, quizalofop-ethyl, diphenamid, metolachlor, and clomazone in tobacco samples were successfully separated and detected at levels as low as 0.0043-0.0086 mg/kg within 5 min using a nonpolar high strength silica C18 selectivity for bases column and methanol as the cosolvent of the mobile phase of carbon dioxide (75-99.9%, v/v). Analysis of tobacco samples had recoveries of 69.8-95.0%, limit of quantitation of 0.0127-0.0245 mg/kg, limit of detection of 0.0043-0.0086 mg/kg, and correlation coefficient of >0.9990. Results support this method as an efficient alternative to current methodologies for the determination of herbicide residues in tobacco.
authors.affiliation: College of Food Science and Engineering, Northwest A&F University, Shannxi, China; College of Food and Biological engineering, Xuchang University, Henan, China.
authors.forename: Weiyun
authors.initials: W
authors.lastname: Guo
authors.forename: Zhaoyang
authors.initials: Z
authors.lastname: Bian
authors.forename: Daohong
authors.initials: D
authors.lastname: Zhang
authors.forename: Gangling
authors.initials: G
authors.lastname: Tang
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Jianlong
authors.initials: J
authors.lastname: Wang
authors.forename: Zhonghao
authors.initials: Z
authors.lastname: Li
authors.forename: Fei
authors.initials: F
authors.lastname: Yang
keywords: Herbicide residues; Tobacco; Ultraperformance convergence chromatography