title: A convenient method for determination of quizalofop-p-ethyl based on the fluorescence quenching of eosin Y in the presence of Pd(II).
abstract: A convenient fluorescence quenching method for determination of Quizalofop-p-ethyl(Qpe) was proposed in this paper. Eosin Y(EY) is a red dye with strong green fluorescence (λex/λem=519/540nm). The interaction between EY, Pd(II) and Qpe was investigated by fluorescence spectroscopy, resonance Rayleigh scattering(RRS) and UV-Vis absorption. Based on changes in spectrum, Pd(II) associated with Qpe giving a positively charged chelate firstly, then reacted with EY through electrostatic and hydrophobic interaction formed ternary chelate could be demonstrated. Under optimum conditions, the fluorescence intensity of EY could be quenched by Qpe in the presence of Pd(II) and the RRS intensity had a remarkable enhancement, which was directly proportional to the Qpe concentration within a certain concentration range, respectively. Based on the fluorescence quenching of EY-Pd(II) system by Qpe, a novel, convenient and specific method for Qpe determination was developed. To our knowledge, this is the first fluorescence method for determination of Qpe was reported. The detection limit for Qpe was 20.3ng/mL and the quantitative determination range was 0.04-1.0μg/mL. The method was highly sensitive and had larger detection range compared to other methods. The influence of coexisting substances was investigated with good anti-interference ability. The new analytical method has been applied to determine of Qpe in real samples with satisfactory results.
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China.
authors.forename: Huan
authors.initials: H
authors.lastname: Wu
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China.
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China.
authors.forename: Xuanping
authors.initials: X
authors.lastname: Tan
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Key Laboratory of Water Environment Evolution and Pollution Control in Three Gorges Reservoir, Chongqing Three Gorges University, Wanzhou, Chongqing, 404100, P.R. China; School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, P.R. China. Electronic address: flyjd6400@163.com.
authors.forename: Jidong
authors.initials: J
authors.lastname: Yang
keywords: Eosin Y; Fluorescence; Pd(II); Quizalorfop-p-ethyl; RRS