Metal-organic frameworks and their derivatives as signal amplification elements for electrochemical sensing

Electrochemical sensor is a promising detection device with the characteristics of simplicity, rapidity, portability, and high sensitivity. With the increasing demands for ultrasensitive detection, extensive signal amplification strategies have been explored and developed to improve the performance of electrochemical sensor. Metal-organic frameworks (MOFs) hold enormous potential for electrochemical signal amplification owing to their attractive properties, including high porosity, superior surface area, unsaturated metal sites, and tunable structure and chemical functionality. In this review, we summarize the recent progress of MOFs and their derivatives as signal amplification elements in electrochemical sensing. Five different signal amplification routes of MOFs and their derivatives are systematically presented, including MOFs and their derivatives as support platforms, catalysts, carriers of signal elements, signal probes, and concentrators. Moreover, an outlook section of offering some insights on the future directions and prospects of MOFs and their derivatives in electrochemical sensing is highlighted with the purpose of conquering current restrictions by exploring more innovative approaches.