Hu Rong, Zhang Xi, Chi Kuan-Neng, Yang Tong, Yang Yun-Hui
College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming, Yunnan 650500, People's Republic of China.
ACS Appl Mater Interfaces. 2020 Jul 8;12(27):30770-30778. doi: 10.1021/acsami.0c06291. Epub 2020 Jun 23.
In this study, a ratiometric electrochemical sensor based on metal-organic frameworks (MOFs) was developed for sensing of multiplex metal ions. The bifunctional MOFs were prepared in a way to integrate two signal tags and a detection probe. In the presence of target metal ions, the target metal ions can replace the framework metal-ion center in the original MOFs through an ion-exchange reaction, leading to ratiometric electrochemical signals under different applied potentials. One consisted of the Cu signal generated from electroactive MOFs selected as internal reference signals. The other consisted of the signal induced by other target metal ions. Using the / signal as the output, the prepared ratiometric probe was able to eliminate disturbance caused by the sensing environment. Moreover, the large surface area and abundant active sites in MOFs produced a multiplex ratiometric electrochemical sensor with improved characteristics in terms of reproducibility, stability, and sensitivity. The sensor was also simple without sophisticated instrumentation, amplification processes, or an acid dissolution/preconcentration procedure, hence promising for practical applications.
在本研究中，开发了一种基于金属有机框架（MOF）的比率型电化学传感器，用于检测多种金属离子。通过整合两个信号标签和一个检测探针的方式制备了双功能MOF。在目标金属离子存在的情况下，目标金属离子可通过离子交换反应取代原始MOF中的骨架金属离子中心，从而在不同施加电位下产生比率型电化学信号。一个信号由选为内部参考信号的电活性MOF产生的铜信号组成。另一个信号由其他目标金属离子诱导产生。以该比率信号作为输出，所制备的比率型探针能够消除传感环境引起的干扰。此外，MOF的大表面积和丰富的活性位点产生了一种在重现性、稳定性和灵敏度方面具有改进特性的多比率型电化学传感器。该传感器也很简单，无需复杂的仪器、放大过程或酸溶解/预浓缩程序，因此在实际应用中很有前景。
