Herein, an enzyme-free fluorescent aptasensor was introduced for the ultrasensitive quantification of lead (Pb) ion as a hazardous pollutant of the environment and foodstuffs. A nanocomposite of zeolitic imidazolate frameworks-8 and gold nanoparticles (ZIF-8@AuNPs) was utilized as an efficient quencher of the fluorescence intensity of carboxyfluorescein (FAM) signal reporter. The establishment of a hybrid structure between attached aptamer on ZIF-8@AuNPs nanocomposite, and its FAM-tagged complementary (CP) strand decreased the fluorescence response. The preferential binding between the aptamer and Pb released CP strands, which retrieved the fluorescence signal. The aptasensor could assess Pb in the linear concentration range of 1 pM-1 nM with a detection limit (LOD) of 0.24 pM. Besides, it could quantify Pb in various samples, including fish, shrimp, tap water, milk, and serum samples. The developed aptasensor with the superiorities of easiness, cost-effectiveness, easy-to-operate, and rapidness is promising for controlling marine foodstuff safety.

中文翻译：

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金纳米粒子/金属有机骨架晶格介导的灵敏适体传感器用于检测海产品中的Pb2+离子


本文引入了一种无酶荧光适体传感器，用于对环境和食品中有害污染物铅 (Pb) 离子进行超灵敏定量。沸石咪唑酯框架 8 和金纳米粒子 (ZIF-8@AuNPs) 的纳米复合材料被用作羧基荧光素 (FAM) 信号报告基因荧光强度的有效猝灭剂。 ZIF-8@AuNPs 纳米复合材料上附着的适体与其 FAM 标记的互补 (CP) 链之间建立的混合结构降低了荧光响应。适体和 Pb 之间的优先结合释放了 CP 链，从而恢复了荧光信号。适体传感器可以在 1 pM-1 nM 的线性浓度范围内评估 Pb，检测限 (LOD) 为 0.24 pM。此外，它还可以定量各种样品中的 Pb，包括鱼、虾、自来水、牛奶和血清样品。所开发的适配体传感器具有简单、成本效益、易于操作和快速等优点，有望用于控制海洋食品安全。