posted on 2024-02-02, 09:05authored byZhuzhen Chen, Tingting Zhang, Yu Liu, Xue Zhang, Linwei Chen, Zhiquan Zhang, Nannan Lu
The rational construction of nanomaterials with boosted
peroxidase
(POD)-like activity is momentous in artificial enzyme design and biological
catalytic fields. Herein, a hybrid nanozyme, gold nanoparticles/N-doped
porous carbon (AuNPs/NPC), is fabricated via a supramolecular assembly-assisted
pyrolysis strategy and engineered as a peroxidase mimic. In this strategy,
a melamine-cyanurate supramolecular aggregate can be employed not
only as a self-vanishing template to gain porous morphology but also
as a nitrogen source to achieve an exceptional high N doping. The
obtained NPC is then subsequently used to immobilize AuNPs via an
in situ reduction approach. Benefiting from well-dispersed ultrafine
AuNPs, high N content, hierarchical porous architecture, and the synergistic
effect of AuNPs and NPC, the fabricated nanozyme exhibits enhanced
POD-like activity, making it a potential alternative to peroxidase
mimics. Besides, the AuNPs/NPC shows highly electrocatalytic properties,
which could serve as a signal amplification platform for ultrasensitively
detecting hydrogen peroxide (H2O2). The hybrid
nanozyme-based electrochemical sensor shows a linear relationship
within 0.2–7000 μM. Significantly, the sensitivity and
limit of detection of the fabricated sensor are 285.9 μA mM–1 cm–2 and 67 nM, respectively. Also,
this biosensor is applied to detect H2O2 in
human serum samples and A549 cells with desirable results. Therefore,
the present work offers a facile strategy for the fabrication of a
high N-contained hybrid nanozyme to simulate the catalytic activity
of natural enzymes and exhibits broad prospects in biosensing, mimicking-enzyme
catalytic fields, and clinical diagnosis.