title: [Direct determination of isocarbophos by using oil-soluble CdSe quantum dots as fluorescence probe].
abstract: A simple, rapid and direct approach to isocarbophos determination was developed based on the fluorescence quenching of oil-soluble CdSe quantum dots by isocarbophos. Under the optimized conditions, the linear range of oil-soluble CdSe QDs fluorescence intensity versus the concentration of isocarbophos was 2.30 x 10(-1) - 1.09 x 10(-5) mol x L(-1), with a correlation coefficient of 0.999 9 and a limit of detection of 1.1 x 10(-7) mol x L(-1). The proposed method has been applied to the determination of isocarbophos in rice and wheat flour with standard recoveries of 93.3%-105.0%. The fluorescence quenching mechanism was further investigated by using UV-Vis absorption spectra and time-resolved fluorescence spectrum. The results indicated that the fluorescence quenching of oil-soluble CdSe QDs by isocarbophos was caused by the change of the surface state which resulted in the enhancement of the surface defect and the occurrence of the non-radiational recombination.
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China. huangs@whu.edu.cn
authors.forename: Shan
authors.initials: S
authors.lastname: Huang
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China.
authors.forename: Jian-Qiang
authors.initials: JQ
authors.lastname: Ma
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Xiao
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China.
authors.forename: Ming-Yue
authors.initials: MY
authors.lastname: Dong
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China.
authors.forename: Xue-Hua
authors.initials: XH
authors.lastname: Li
authors.affiliation: College of Chemistry and Life Science, Guangxi Teachers Education University, Nanning 530001, China.
authors.forename: Qiu-Ling
authors.initials: QL
authors.lastname: Luo