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Updated: Nov 10, 2025

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Mixed Metal Metal-Organic Frameworks Derived Carbon Supporting ZnFe2O4/C for High-Performance Magnetic Particle
Zhenqi Jiang1,2, Xiao Han3,2, Yang Du3,4
1Cixi Institute of Biomedical Engineering, International Cooperation Base of Biomedical Materials Technology and Application, CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Engineering Research Center for Biomedical Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Abstract:
Recently, magnetic particle imaging (MPI) has shown diverse biomedical applications such as cell tracking, lung perfusion, image-guided hyperthermia, and so forth. However, the currently reported MPI agents cannot achieve the possible theoretical detection limit of MPI (20 nM). A previous theoretical study has shown that the MPI performance of superparamagnetic iron oxide nanoparticles (SPIONs) can be enhanced by carbon supporting and metal doping. In the current study, a series of mixed metal metal-organic framework-derived carbon supporting SPIONs were synthesized by pyrolysis. Among the synthesized SPIONs, the MPI signal intensity of ZnFe2O4/C@PDA was found to be 4.7 times higher than the commercial MPI contrast (Vivotrax) having the same Fe concentration. ZnFe2O4/C@PDA also showed the highest MPI intensity in tumor-bearing-mice among all tested samples. Furthermore, they were found highly biocompatible and showed linear cell quantification. This work can open new avenues for the design and development of novel and high-performance MPI agents.
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