College of Environmental Science and Engineering, Biomedical Multidisciplinary Innovation Research Institute, Shanghai East Hospital, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai 200092, China.
Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Anal Chem. 2021 Jun 8;93(22):8010-8018. doi: 10.1021/acs.analchem.1c01094. Epub 2021 May 21.
Silver (Ag) is a widely used heavy metal, and its oxidation state (Ag) causes serious harm to organisms after bioaccumulation and biomagnification, posing urgent demand for the rapid, efficient, and simply operated Ag detection techniques. In this work, a fast, portable, and label-free Ag detection sensor based on a TiCT MXene field-effect transistor (FET) is reported. The TiCT MXene works as the sensing element in the FET sensor, which shows excellent sensing performance, i.e., fast response (few seconds) and good sensitivity and selectivity to Ag without any detection label or probe. Utilizing the visual photograph, transmission electron microscopy image, and Ag elemental mapping analysis, the sensing mechanism of the label-free TiCT MXene FET sensor is demonstrated to be the reduction of Ag and the formation of Ag nanoparticles (AgNPs). Moreover, Ag detection in real samples shows that the proposed FET devices have satisfactory sensing capability for Ag in tap water and river water. This study puts forward a novel FET strategy for Ag detection in aqueous systems, which is of essential and inspiring meaning for motivating the potential applications of MXene-based sensor devices in analytical applications and the realization of on-site environmental monitoring.
银（Ag）是一种广泛使用的重金属，其氧化态（Ag）在生物积累和生物放大后对生物体造成严重危害，因此迫切需要快速、高效、简单操作的 Ag 检测技术。在这项工作中，报道了一种基于 TiCT MXene 场效应晶体管（FET）的快速、便携且无标记的 Ag 检测传感器。TiCT MXene 作为 FET 传感器中的传感元件，具有优异的传感性能，即对 Ag 具有快速响应（几秒钟内）和良好的灵敏度和选择性，而无需任何检测标记或探针。利用可视化照片、透射电子显微镜图像和 Ag 元素映射分析，证明了无标记 TiCT MXene FET 传感器的传感机制是 Ag 的还原和 Ag 纳米颗粒（AgNPs）的形成。此外，在实际样品中的 Ag 检测表明，所提出的 FET 器件对自来水中和河水中的 Ag 具有令人满意的传感能力。本研究为水相体系中的 Ag 检测提出了一种新颖的 FET 策略，对于推动基于 MXene 的传感器设备在分析应用中的潜在应用和实现现场环境监测具有重要和启发意义。
