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Updated: Aug 7, 2026
07:37
An Adoptive Transfer Model of Rheumatoid Arthritis in Mice
Published on: June 6, 2025
Ferromagnetic Coupling in Dual-Atom Nanozymes Enables Spin-Favorable Catalase-Like Catalysis for Rheumatoid Arthritis
Xiangfu Meng1, Ruofei Zhang2, Luzheng Xu3
1High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui, P. R. China.
Angewandte Chemie (International Ed. in English)
|August 5, 2026
Summary
We engineered iron dual-atom (Fe DA) nanozymes with enhanced catalase-like activity by optimizing the nitrogen coordination environment. This magnetic coupling strategy significantly boosts performance and offers therapeutic potential for inflammatory diseases.
Area of Science:
- Materials Science
- Nanotechnology
- Catalysis
Background:
- Iron dual-atom (Fe DA) nanozymes show promise as catalase mimics but face challenges in performance enhancement and mechanistic understanding.
- Developing efficient Fe DA nanozymes requires strategies to optimize their structure and catalytic activity.
Purpose of the Study:
- To design and synthesize novel Fe DA nanozymes with improved catalase-like (CAT-like) activity using a cascade strategy.
- To elucidate the mechanism behind the enhanced CAT-like activity through experimental and computational studies.
- To evaluate the therapeutic potential of the developed nanozymes in a rheumatoid arthritis model.
Main Methods:
- A cascade strategy involving vacancy induction and electrostatic adsorption was used to create Fe DA nanozymes with different nitrogen coordination environments (pyrrolic-N vs. pyridinic-N).
- Catalase-like activity was measured, and mechanistic insights were gained through density functional theory (DFT) calculations and other studies.
- The anti-inflammatory and oxidative stress-alleviating effects were assessed in rheumatoid arthritis models.
Main Results:
- The py-Fe-DA nanozyme, with pyridinic-N coordination, exhibited a significantly higher CAT-like activity (100 U mg⁻¹) compared to pr-Fe-DA (42 U mg⁻¹), the highest reported to date.
- A transition from antiferromagnetic to ferromagnetic coupling in py-Fe-DA, driven by pyridinic-N coordination, facilitates spin-favorable H₂O₂ activation and lowers the energy barrier for catalysis.
- py-Fe-DA demonstrated efficacy in alleviating oxidative stress and inflammation in rheumatoid arthritis models.
Conclusions:
- Modulating the nitrogen coordination environment and leveraging magnetic coupling is crucial for designing high-performance Fe DA nanozymes.
- Magnetic coupling serves as a key descriptor for CAT-like activity, opening avenues for rational nanozyme design.
- Magnetic-coupling engineering represents a powerful strategy for developing advanced nanozymes with therapeutic applications.
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