Fe3O4/Ni nanoparticles anchored nitrogen-doped porous carbon derived from core-shell MOF for simultaneous electrochemical detection of dopamine and 5-hydroxytryptamine

Pre-designed core-shell metal-organic frameworks (MOFs@MOFs) with customized functionalities can enhance the material properties compared to conventional single MOFs. The porous carbon composites derived from MOFs@MOFs also have excellent functionality due to the presence of multiple metal/metal oxide nanoparticles. This paper synthesized a novel MOFs@MOFs composite (MIL-101(Fe)@Ni-MOF) with a core-shell structure with MIL-101(Fe) as the core and Ni-MOF as the shell. After pyrolysis of the above composite, nitrogen-doped porous carbon (Fe 3 O 4 /Ni@NPC) anchored with Fe 3 O 4 nanoparticles and Ni nanoparticles with synergistic catalytic effects were constructed. Fe 3 O 4 /Ni@NPC exhibited synergistic catalytic effects for the synchronous and ultra-sensitive detection of dopamine (DA) and 5-hydroxytryptamine (5-HT) with a detection limit of 0.165 μM for DA and 0.327 μM for 5-HT. Highly accurate and sensitive target detection was also achieved in experiments with human serum and PC12 cells, which was of great clinical importance.