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Asymmetrically coordinated single-atom iron nanozymes with Fe-N1C2 structure: A peroxidase mimetic for melatonin detection

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Abstract

Owing to the unique coordination environment and high atom utilization efficiency, single atom catalysts have been considered as an ideal artificial enzyme to mimic natural enzymes. Herein, single-atom Fe nanozyme anchored on N-doped Ti3C2Tx (Fe SA/N-Ti3C2Tx) with asymmetrically coordinated Fe-N1C2 configuration is synthesized by vacancy capture and heteroatom do** strategy, which exhibits excellent peroxidase-like activity. Based on the results of peroxidase catalytic kinetics and X-ray adsorption fine spectroscopy, the Fe-N1C2 active sites in Fe SA/N-Ti3C2Tx are responsible for the excellent performance. Furthermore, the developed Fe SA/N-Ti3C2Tx can be employed to quantitative detection of melatonin (MT), which shows a wide linear detection range (0.01–100 µM) and an excellent detection limit (7.3 nM) in buffer, 0.01–100 µM and 7.8 nM in serum samples. Our work proves that MXene-based single atoms can be promising nanozyme in the field of bioassays.

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Acknowledgements

This work was supported by Bei**g Natural Science Foundation (No. 2212018) and the National Natural Science Foundation of China (No. 21801015). The authors thank the BL1W1B and 4B7B in the Bei**g Synchrotron Radiation Facility (BSRF) for help with characterizations.

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  1. Lihong Lin, Heng Li, and Hongfei Gu contributed equally to this work.

Authors and Affiliations

  1. Energy & Catalysis Center, School of Materials Science and Engineering, Bei**g Institute of Technology, Bei**g, 100081, China

    Lihong Lin, Hongfei Gu, Zhiyi Sun, Hang Li & Zhuo Chen

  2. Department of Chemistry, Capital Normal University, Bei**g, 100081, China

    Heng Li, Juan Huang, Zhenni Qian & Zhengbo Chen

  3. The Key Laboratory of Resources and Environmental System Optimization, Ministry of Education (MOE), College of Environmental Science and Engineering, North China Electric Power University, Bei**g, 102206, China

    Juzhe Liu & Juanjuan Qi

  4. School of Chemistry, Beihang University, Bei**g, 100191, China

    Hongyan **, Pengfei Wu & Qingqing Liu

  5. Institute of High Energy Physics, Chinese Academy of Science, Bei**g, 100049, China

    Shuhu Liu & Lirong Zheng

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  1. Lihong Lin
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Correspondence to Zhuo Chen, Zhengbo Chen or Juanjuan Qi.

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Asymmetrically coordinated single-atom iron nanozymes with Fe-N1C2 structure: A peroxidase mimetic for melatonin detection

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Lin, L., Li, H., Gu, H. et al. Asymmetrically coordinated single-atom iron nanozymes with Fe-N1C2 structure: A peroxidase mimetic for melatonin detection. Nano Res. 16, 4751–4757 (2023). https://doi.org/10.1007/s12274-022-5211-8

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