Label-free and ultrasensitive fluorescence assay for Fe3 detection using DNA-Templated Ag nanoclusters

作者：Zhang, Zhiqing^*; Liu, Tingting; Yue, Changle; Wang, Shanshan; Ma, Jie; Zhou, Ting^*; Wang, Fang; Wang, Xiufeng; Zhang, Guodong

来源：Colloids and Surfaces A: Physicochemical and Engineering Aspects , 2019, 579: UNSP 123656.

DOI：10.1016/j.colsurfa.2019.123656

• Nanocluster
• DNA-templated
• Label-free fluorescent sensor
• Fe3

We report for the first time the selective and sensitive detection of Fe3 by a label-free fluorescent sensor base on AgNCs@C30. AgNCs@C30 was synthesized, and the averaged size is about 3.0 nm, and the maximal excitation and emission wavelengths were 335 nm and 480 nm, respectively. Fe3 caused a significantly fluorescence quenching of AgNCs@C30, and a novel and label-free nanosensor for detecting Fe3 was developed with optimum detection of 303.15 K and 2 min. The linear range for Fe3 detection was 0.1(similar to)12 mu M with the corresponding limit of detection (LOD) of 86 nM. Furthermore, the preliminary detection mechanism was discussed in detail, and the fluorescence quenching was deemed to result from AgNCs@C30 aggregation induced with a relatively weak mutual collision between AgNCs@C30 and Fe3 . This strategy detection of Fe3 will provide a valuable reference for the detection of metal ions by using nanocluster.