Dong Chen, Wang Zhuqing, Zhang Yujie, Ma Xuehua, Iqbal M Zubair, Miao Lijing, Zhou Zhuangwei, Shen Zheyu, Wu Aiguo
CAS Key Laboratory of Magnetic Materials and Devices & Key Laboratory of Additive Manufacturing Materials of Zhejiang Province & Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences , Ningbo, Zhejiang 315201, China.
School of Chemistry and Chemical Engineering, Anqing Normal College , Anqing, Anhui 246001, China.
ACS Sens. 2017 Aug 25;2(8):1152-1159. doi: 10.1021/acssensors.7b00257. Epub 2017 Aug 2.
Developing thiosulfate (SO) sensors with silver nanoparticles (AgNPs) for analysis of aqueous solutions with the interference of other anions remains challenging. In this study, we propose a new strategy for excellent selective colorimetric detection of SO. The nonmorphological transition of AgNPs leading to a color change from yellow to brown is verified by UV-vis, TEM, DLS, SEM, and XPS analyses. The sensor exhibits high sensitivity with detection limits of 1.0 μM by naked-eye determination and 0.2 μM by UV-vis spectroscopy analysis. The linear relationship (R = 0.998) between the (A - A)/A values and SO concentrations from 0.2 μM to 2.0 μM indicates that the fabricated AgNPs-based colorimetric sensor can be employed for quantitative assay of SO. Colorimetric responses are also monitored using the built-in camera of a smartphone. The sensor shows a linear response to SO in 0-20.0 μM solutions under the optimized conditions and is thus more suitable for rapid on-site tests than other detection methods. A smartphone application (app) is downloaded under Android or IOS platforms to measure the RGB (red, green, blue) values of the colorimetric sensor after exposure to the analyte. Following data processing, the RGB values are converted into concentration values by using preloaded calibration curves. Confirmatory analysis indicates that the proposed SO colorimetric sensor exhibits feasibility and sensitivity for SO detection in real environmental samples.
开发用于分析存在其他阴离子干扰的水溶液的含银纳米颗粒（AgNP）硫代硫酸盐（SO）传感器仍然具有挑战性。在本研究中，我们提出了一种用于出色选择性比色检测SO的新策略。通过紫外可见光谱、透射电子显微镜、动态光散射、扫描电子显微镜和X射线光电子能谱分析验证了AgNP的非形态转变导致颜色从黄色变为棕色。该传感器具有高灵敏度，肉眼测定的检测限为1.0 μM，紫外可见光谱分析的检测限为0.2 μM。（A - A）/A值与0.2 μM至2.0 μM的SO浓度之间的线性关系（R = 0.998）表明，所制备的基于AgNP的比色传感器可用于SO的定量测定。还使用智能手机的内置摄像头监测比色响应。该传感器在优化条件下对0 - 20.0 μM溶液中的SO呈现线性响应，因此比其他检测方法更适合快速现场测试。在安卓或iOS平台下载智能手机应用程序（app），以测量比色传感器在暴露于分析物后的RGB（红、绿、蓝）值。经过数据处理后，通过使用预加载的校准曲线将RGB值转换为浓度值。验证性分析表明，所提出的SO比色传感器在实际环境样品中检测SO具有可行性和灵敏度。
