A novel hollow nanostructure with charge collection function based on bimetallic MOFs: Ameliorating the catalytic reaction of norepinephrine bitartrate in serum

Abstract

Bimetallic hollow organic frameworks (H-MOFs) have been brought into focus in recent years and are being researched in various disciplines. However, there haven't been many reports of their application in electrochemical sensing. In this study, an innovative 3D hollow nanomaterial that resembles a "chocolate sugar cube" was created using a quick and easy hydrothermal synthesis technique. On this basis, a series of core-shell structured materials (H-MOF@PPy) were obtained by modifying polypyrrole (PPy) on the surface of H-ZnNi-MOF using an in-situ synthesis method. With its substantial specific surface area, distinctive frame structure, and wide range of active sites, H-MOF@PPy can be used to build an electrochemical sensor that can detect norepinephrine bitartrate (NE-B). Under optimal conditions, this assay platform has the advantages of a wide measurement range (0.1–10 and 10–1000 μM), high sensitivity (0.288 and 0.112 μA·μM·cm−2), and a low detection limit (0.033 μM). In addition, the sensor demonstrates high selectivity for NE-B in the presence of other coexisting interfering substances and can be used for over 60 cycles without significant loss of analytical performance. The suggested method was utilized for the measurement of NE-B in actual human serum with satisfactory results. It is firmly believed that our study will pave a feasible way for development of high-performance bimetallic hollow MOF-based electrochemical sensors.