posted on 2024-02-02, 17:03authored byYangguang Li, Yuxin Dong, Rongjiang Wang, Zhenghao Lin, Jiajun Lin, Xinyi Ji, Bang-Ce Ye
Laccase, a member of the copper oxidase family, has been
used as
a green catalyst in the environmental and biochemical industries.
However, laccase nanoenzymes are limited to materials with copper
as the active site, and noncopper laccase nanoenzymes have been scarcely
reported. In this study, inspired by the multiple copper active sites
of natural laccase and the redox Cu2+/Cu+ electron
transfer pathway, a novel nitrogen/nickel single-atom nanoenzyme (N/Ni
SAE) with high laccase-like activity was prepared by inducing Ni and
dopamine precipitation through a controllable water/ethanol interface
reaction. Compared with that of laccase, the laccase activity simulated
by N/Ni SAE exhibited excellent stability and reusability. The N/Ni
SAE exhibited a higher efficiency toward the degradation of 2,4-dichlorophenol,
hydroquinone, bisphenol A, and p-aminobenzene. In
addition, a sensitive electrochemical biosensor was constructed by
leveraging the laccase-like activity of N/Ni SAE; this sensor offered
unique advantages in terms of catalytic activity, selectivity, stability,
and repeatability. Its detection ranges for quercetin were 0.01–0.1
and 1.0–100 μM, and the detection limit was 3.4 nM. It
was also successfully used for the quantitative detection of quercetin
in fruit juices. Therefore, the single-atom biomimetic nanoenzymes
prepared in this study promote the development of a new electrochemical
strategy for the detection of various bioactive molecules and show
great potential for practical applications.