关键词: FeCo-MOF, 金超微电极, 原位电沉积, 电分析, 肾上腺素

Abstract: Metal-organic framework (MOF) nanostructures have emerged as a prominent class of materials in the advancement of electrochemical sensors. The rational design of bimetallic MOF-functionalized microelectrode is of importance for improving the electrochemical performance but still in great challenge. In this work, bimetallic FeCo-MOF nanostructures were assembled onto a gold disk ultramicroelectrode (Au UME, 5.2 µm in diameter) via an in-situ electrodeposition method, which enhanced the sensitive detection of epinephrine (EP). The FeCo-MOF, characterized by a nanoflower-like morphology, was uniformly dispersed on the ultra-micro substrate. The FeCo-MOF/Au UME demonstrated excellent electrochemical performance on the detection of EP with a high sensitivity of 36.93 μA μM^-1 cm^-2 and a low detection limit of 1.28 μM. It can be attributed to the non-linear diffusion of EP onto the ultra-micro working substrate, coupled with synergistical catalytic activity of the bimetallic Fe, Co within MOF structure. Furthermore, FeCo-MOF/Au UME has been successful applied to the analysis of EP in human serum samples, yielding high recovery rates. These results not only contribute to the expansion of the research area of electrochemical sensors but also provide novel insights and directions for the development of high-performance MOF-based electrochemical sensors.

Key words: FeCo-MOF;Au disk ultramicroelectrode, in-situ electrodeposition, electroanalysis, epinephrine