title: In-situ formation of ion-association nanoparticles induced enhancements of resonance Rayleigh scattering intensities for quantitative analysis of trace Hg(2+) ions in environmental samples.
abstract: In this paper, Hg(2+) ions are demonstrated to form anionic [HgI4](2-) complexes after interacting with massive amount of I(-) ions. Subsequently, the addition of tetradecyl pyridyl bromide (TPB) can make [HgI4](2-) anionic complexes react with univalent tetradecyl pyridyl cationic ions (TP(+)), forming dispersed ion-association complexes (TP)2(HgI4). Due to the extrusion action of water and Van der Waals force, the hydrophobic ion-association complexes aggregate together, forming dispersed nanoparticles with an average size of about 8.5nm. Meanwhile, resonance Rayleigh scattering (RRS) intensity is apparently enhanced due to the formation of (TP)2(HgI4) ion-association nanoparticles, contributing to a novel technique for Hg(2+) detection. The wavelength of 365nm is chosen as a detection wavelength and several conditions affecting the RRS responses of Hg(2+) are optimized. Under the optimum condition, the developed method is used for the determination of Hg(2+) in aqueous solution and the detection limit is estimated to be 0.8ngmL(-1). Finally, the practical application of the developed method can be confirmed through the detections of Hg(2+) in waste and river water samples with satisfactory results.
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China; Environmental Monitoring Center in Chongqing City, Chongqing 400020, China.
authors.forename: Qingling
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Banglin
authors.initials: B
authors.lastname: Li
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Hu
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China. Electronic address: liusp@swu.edu.cn.
authors.forename: Shaopu
authors.initials: S
authors.lastname: Liu
authors.affiliation: Environmental Monitoring Center in Chongqing City, Chongqing 400020, China.
authors.forename: Gangcai
authors.initials: G
authors.lastname: Chen
keywords: Environmental monitoring; Hg(2+) detection; Ion-association nanoparticles; Resonance Rayleigh scattering