Zhang Ziwei, Wang Yanru, Chen Qichen, Tan Xiaojiang, Hu Xialin, An Yarui, Liu Meichuan
School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, China; Institute of Bismuth and Rhenium, School of Materials and Chemistry, University of Shanghai for Science and Technology, Shanghai, 200093, China.
Talanta. 2024 Sep 1;277:126409. doi: 10.1016/j.talanta.2024.126409. Epub 2024 Jun 18.
Atrazine (ATZ) is a widely used herbicide that can cause serious harm to organisms and ecosystems. An immobilization-free photoelectrochemical (PEC) aptasensor has been herein developed for ATZ based on aptamer molecular gate functionalized mesoporous SiO@MB controlled release system. Compared with traditional immobilization-based sensors, immobilization-free sensors (IFSs) avoid the modification of the recognition element on the electrode surface. Mesoporous SiO with large surface area and good biocompatibility can be used as nanocontainers to stably encapsulate the signal shuttle molecule methylene blue (MB). The bifunctional aptamer (APT) is used not only as the recognition element for ATZ but also as the signal switch to block or release MB. In the presence of ATZ, the specific recognition between ATZ and APT will cause the detachment of APT from the surface of SiO, thus the molecular gate will open and release MB. Due to pH modulation, the positively charged MB can reach the surface of the negatively charged Ti(III) self-doped TiO NTs (Ti(III)-TiO NTs) electrode to act as an electron donor, which increases the photocurrent. The immobilization-free aptasensor has shown ultrasensitive detection of ATZ with a wide linear range from 1.0 pM to 100.0 nM and a low detection limit of 0.1 pM. In addition, the sensor has excellent selectivity, stability and anti-interference ability, and has been used in real water sample analysis successfully. This strategy has provided a new idea for the design of advanced immobilization-free PEC sensors for environmental pollutant detection.
阿特拉津（ATZ）是一种广泛使用的除草剂，会对生物体和生态系统造成严重危害。本文基于适配体分子门功能化介孔SiO@MB控释系统开发了一种用于检测ATZ的无固定化光电化学（PEC）适配体传感器。与传统的基于固定化的传感器相比，无固定化传感器（IFS）避免了识别元件在电极表面的修饰。具有大表面积和良好生物相容性的介孔SiO可作为纳米容器，稳定地封装信号穿梭分子亚甲基蓝（MB）。双功能适配体（APT）不仅用作ATZ的识别元件，还用作阻断或释放MB的信号开关。在ATZ存在的情况下，ATZ与APT之间的特异性识别会导致APT从SiO表面脱离，从而分子门将打开并释放MB。由于pH调节，带正电荷的MB可以到达带负电荷的Ti(III)自掺杂TiO纳米管（Ti(III)-TiO NTs）电极表面，充当电子供体，从而增加光电流。该无固定化适配体传感器对ATZ的检测具有超灵敏性，线性范围宽，从1.0 pM到100.0 nM，检测限低至0.1 pM。此外，该传感器具有优异的选择性、稳定性和抗干扰能力，并已成功应用于实际水样分析。该策略为设计用于环境污染物检测的先进无固定化PEC传感器提供了新思路。
