pH-controlled fluorescence changes in a novel semiconducting polymer dot/pyrogallic acid system and a multifunctional sensing strategy for urea, urease, and pesticides
pH-controlled fluorescence changes in a novel semiconducting polymer dot/pyrogallic acid system and a multifunctional sensing strategy for urea, urease, and pesticides
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新型半导体聚合物点/焦没食子酸系统中 pH 控制的荧光变化以及尿素、尿素酶和农药的多功能传感策略
DOI：
10.1039/c7ay02284k
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发表时间：
2017-12-21
影响因子：
3.1
通讯作者：
Li, Yongxin
中科院分区：
文献类型：
--
作者：
Huang, Hui;Li, Jiao;Li, Yongxin
建立了一种新型的多功能半导体聚合物点（Pdots）/焦性没食子酸（PA）荧光传感体系，用于尿素、脲酶和农药的荧光检测。Pdots/PA体系是pH可控的，在pH 6.0下发射强荧光。但在碱性条件下，PA转化为醌结构，成为一种有效的荧光猝灭剂，导致Pdots/PA体系的荧光猝灭。此外，尿素在脲酶存在下水解，释放羟基，将PA转化为其醌结构，导致Pdots/PA系统的荧光猝灭。因此，建立了一种灵敏的尿素和脲酶检测方法。尿素和脲酶的检测限分别为0.02 mM和0.08 U L-1。农药，如乐果，能够抑制脲酶活性，导致Pdots/PA系统的荧光强度的恢复。因此，也可以实现农药的荧光开启检测。将该系统应用于果蔬样品中农药残留的检测，获得了满意的结果。
A novel multifunctional semiconducting polymer dot (Pdots)/pyrogallic acid (PA) system was successfully established for fluorescence sensing of urea, urease, and pesticides. The Pdots/PA system was pH controllable, emitting strong fluorescence at pH 6.0. However, in an alkaline environment, PA transformed into its quinone structure, which is an efficient fluorescence quencher, resulting in fluorescence quenching of the Pdots/PA system. Furthermore, urea was hydrolyzed in the presence of urease, releasing hydroxyl groups that transformed PA into its quinone structure, resulting in fluorescence quenching of the Pdots/PA system. Therefore, a sensitive detection method for urea and urease was developed. The limits of detection for urea and urease were 0.02 mM and 0.08 U L-1, respectively. Pesticides, such as dimethoate, were able to inhibit the urease activity, resulting in recovery of the fluorescence intensity of the Pdots/PA system. Therefore, the fluorescence turn-on detection of pesticides could be also achieved. A satisfactory result was obtained when using the system to detect pesticides in fruit and vegetable samples.