Wang Yue, Zhai Hongguo, Guo Qi, Zhang Yuhao, Gao Xiaolin, Yang Qingqing, Sun Xia, Guo Yemin, Zhang Yanyan
School of Agricultural Engineering and Food Science, Shandong University of Technology, No. 266 Xincun Xilu, Zibo 255000, China; Shandong Province Engineering Research Center of Vegetable Safety and Quality Traceability, No. 266 Xincun Xilu, Zibo 255000, China; Zibo City Key Laboratory of Agricultural Product Safety Traceability, No. 266 Xincun Xilu, Zibo 255000, China.
School of Agricultural Engineering and Food Science, Shandong University of Technology, No. 266 Xincun Xilu, Zibo 255000, China; Shandong Province Engineering Research Center of Vegetable Safety and Quality Traceability, No. 266 Xincun Xilu, Zibo 255000, China; Zibo City Key Laboratory of Agricultural Product Safety Traceability, No. 266 Xincun Xilu, Zibo 255000, China.
Sci Total Environ. 2023 Mar 10;863:160910. doi: 10.1016/j.scitotenv.2022.160910. Epub 2022 Dec 15.
As a unique nanomachine, DNA Walker can move continuously along a specific orbit to amplify signal. Therefore, based on DNA Walker and endonuclease assisted signal amplification strategy, a novel dual-mode visual electrochemical aptasensor was constructed for the detection of Pb. Ceric dioxide@mesoporous carbon (CeO/CS)@AuNPs not only could improve the conductivity of sensing interface but also could fix the aptamer. DNA Walker moved on the surface of the electrode to realize the pairing with the Ag-γFeO/cDNA probe, forming a special base sequence that could be spliced by the Nb.BbvCI. Under the action of endonuclease Nb.BbvCI, the Ag-γFeO/cDNA probe was continuously sheared and the amount on the electrode was decreased to amplify the signal. Besides, the nanoenzyme of Ag-γFeO could catalyze 3'3'5'5'-tetramethylbenzidine (TMB) to blue color realizing the visual detection of Pb. The sensor has been successfully applied to the visual and accurate rapid detection of Pb in aquatic products. The fabricated method of the sensor open up a new way for visual and accurate the detection of environmental pollutants.
作为一种独特的纳米机器，DNA步行器可以沿着特定轨道连续移动以放大信号。因此，基于DNA步行器和核酸内切酶辅助信号放大策略，构建了一种新型的双模式可视化电化学适体传感器用于检测铅。二氧化铈@介孔碳（CeO/CS）@金纳米粒子不仅可以提高传感界面的导电性，还可以固定适体。DNA步行器在电极表面移动，实现与Ag-γFeO/cDNA探针的配对，形成一种可以被Nb.BbvCI切割的特殊碱基序列。在内切酶Nb.BbvCI的作用下，Ag-γFeO/cDNA探针被连续剪切，电极上的量减少以放大信号。此外，Ag-γFeO纳米酶可以催化3'3'5'5'-四甲基联苯胺（TMB）变蓝，实现铅的可视化检测。该传感器已成功应用于水产品中铅的可视化、准确快速检测。该传感器的制备方法为环境污染物的可视化、准确检测开辟了一条新途径。
