부산대학교 도서관

Abstract: A new fluorescence sensor for detection of cyanide ions (CN−) in aqueous media based on the recovered fluorescence of cysteamine capped CdS quantum dots [Cys-CdS QDs]-Cu2+ system was proposed. The fluorescence intensity of Cys-CdS QDs was quenched by Cu2+ due to the binding of Cu2+ to cysteamine on the surface of the QDs. The degree of fluorescence quenching was proportional to the concentration of Cu2+. However, in the presence of CN−, the fluorescence intensity of Cys-CdS QDs was found to be efficiently recovered. Experimental results showed that the pH of the buffer solution and the concentration of Cu2+ affected the fluorescence intensity upon adding CN−. Under the optimal condition, the recovered fluorescence intensity was linearly proportional to the increasing CN− concentration in the range 2.5–20μM. The limit of detection and the limit of quantification were found to be 1.13μM and 3.23μM, respectively. In addition, among the tested ions, only CN− could turn on the fluorescence intensity suggesting that the [Cys-CdS QDs]-Cu2+ system was a highly selective sensor for CN−. Moreover, this proposed sensor was demonstrated to detect CN− in drinking water with satisfactory results. [Copyright &y& Elsevier]