title: Simultaneous determination of 9-ethylphenanthrene, pyrene and 1-hydroxypyrene in an aqueous solution by synchronous fluorimetry using the double scans method and hydroxyl-propyl beta-cyclodextrin as a sensitizer.
abstract: A novel method for the simultaneous determination of 9-ethylphenanthrene (9-EP), pyrene (Pyr) and 1-hydroxypyrene (1-OH-Pyr) in an aqueous solution using hydroxyl-propyl β-cyclodextrin (HPCD) as a sensitizer has been established. The overlap of the conventional fluorescence spectra of these molecules is resolved using synchronous fluorescence spectrometry with the double scans method. The simultaneous quantitative determination of three compounds was carried out with Δλ=36 nm and Δλ=55 nm. The signals detected at these three wavelengths (i.e., 298 nm, 337 nm and 351 nm) vary linearly when the concentrations of 9-EP, Pyr and 1-OH-Pyr were in the range of 5.00×10(-8)-1.60×10(-6) mol L(-1), 2.00×10(-8)-1.80×10(-6) mol L(-1), and 2.00×10(-8)-1.20×10(-5) mol L(-1), respectively. The limits of detection (LOD) for 9-EP, Pyr and 1-OH-Pyr were 3.97×10(-9) mol L(-1), 5.25×10(-)(9) mol L(-1), 4.20×10(-9) mol L(-1), respectively, with relative standard deviations (R.S.D.) of 1.62%, 2.45% and 1.73% (n=9), respectively. The inclusion behaviors between HPCD and the guest molecules were observed by synchronous fluorimetry and the association constants for the 1:1 complexes with HPCD were determined. The binding and complexation energies for different orientations are discussed. The proposed method was successfully applied to the analysis of 9-EP, Pyr and 1-OH-Pyr in tap and lake water with good recoveries in the range of 92.9-110.0%.
authors.affiliation: State Key Laboratory of Marine Environmental Science of China (Xiamen University), College of the Environment and Ecology, Xiamen University, Xiamen, 361102, PR China.
authors.forename: Zhen-Xuan
authors.initials: ZX
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, PR China.
authors.forename: Ya-Xian
authors.initials: YX
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Marine Environmental Science of China (Xiamen University), College of the Environment and Ecology, Xiamen University, Xiamen, 361102, PR China; Zhangzhou Institute of Technology, Zhangzhou, 363000, PR China. Electronic address: yzhang@xmu.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
keywords: Binding energy; Double scans; HPCD; PAHs; Synchronous fluorimetry