Rapid microwave-assisted synthesis of ZnMn dual-atom nanozymes for cancer catalytic immunotherapy.
ZnMn dual-atom nanozymes showed a significant ability to suppress tumors and reduce metastases in animal models, but further research is needed to determine their effectiveness in humans.
Where it sits
this study against the rest of the glutathione (gsh) corpusSummary and findings
This study measured the efficacy of ZnMn dual-atom nanozymes in cancer immunotherapy. The nanozymes were shown to suppress tumors by approximately 90% and reduce lung metastases by 92% in 4T1 models. The study also reported a rapid synthesis method for these nanozymes using microwave-assisted techniques.
Abstract
Catalytic nanomedicines face a persistent trade-off between structurally defined active sites and rapid synthesis. A microwave-assisted salt-flux conversion is developed that transforms a bimetallic metal-organic framework precursor within 3 min into nitrogen-doped carbon-supported ZnMn dual-atom nanozymes (ZnMn DAzymes). Aberration-corrected HAADF-STEM and dual-edge X-ray absorption fine structure analyses support adjacent Zn-Mn sites with an N-dominated ZnMn-N<sub>6</sub>-like coordination motif. Steady-state kinetics and density functional theory calculations suggest cooperative catalysis: Zn modulates H<sub>2</sub>O<sub>2</sub> adsorption and O-O bond activation, whereas Mn provides stronger H<sub>2</sub>O<sub>2</sub> chemisorption and redox flexibility, jointly enhancing catalase-, peroxidase-, and oxidase-like activities. The resulting cascade decomposes H<sub>2</sub>O<sub>2</sub>, relieves hypoxia, generates reactive oxygen species, and depletes glutathione, inducing mitochondrial dysfunction, immunogenic cell death, cGAS-STING-associated signaling, dendritic-cell maturation, and effector T-cell infiltration. Glutathione-responsive Mn<sup>2+</sup> release additionally enables activatable T<sub>1</sub>-weighted magnetic resonance contrast. Combined with αPD-L1, ZnMn DAzymes suppress primary and distal tumors by approximately 90%, reduce lung metastases by 92%, and prolong survival in 4T1 models. This work provides a rapid route to ZnMn dual-atom nanozymes for catalytic immunotherapy.
Background
This paper addresses the challenge of synthesizing catalytic nanomedicines with defined active sites and rapid production. Prior research has indicated that dual-atom nanozymes can enhance catalytic activities, but the methods for their synthesis have been limited. This study presents a novel microwave-assisted approach that could potentially streamline the production of these nanozymes for therapeutic applications.
Methods
The study utilized a microwave-assisted salt-flux conversion to synthesize ZnMn dual-atom nanozymes from a bimetallic metal-organic framework precursor within 3 minutes. The characterization included aberration-corrected HAADF-STEM and dual-edge X-ray absorption fine structure analyses. The primary outcomes measured were the catalytic activities and the effects on tumor suppression in 4T1 models.
Results
The primary endpoint indicated a 90% tumor suppression when ZnMn DAzymes were combined with αPD-L1. Additionally, there was a reported 92% reduction in lung metastases. The study also noted enhanced catalase-, peroxidase-, and oxidase-like activities due to the cooperative catalysis of Zn and Mn.
Interpretation
The results suggest that the ZnMn dual-atom nanozymes may offer a significant improvement in catalytic immunotherapy compared to previous methods. However, while the statistical significance is notable, the clinical relevance of such findings in human subjects remains to be established. The study's reliance on preclinical models and the lack of long-term follow-up limit the conclusions that can be drawn regarding real-world applications.
Key findings
- 90% tumor suppression when combined with αPD-L1 in 4T1 models.
- 92% reduction in lung metastases.
- Not reported in abstract.
Limitations
- preclinical study in 4T1 models only
- short synthesis time of 3 minutes may not reflect real-world applications
- no long-term follow-up data reported
- not directly tested in human subjects