Construct of Carbon Nanotube-Supported Fe2O3 Hybrid Nanozyme by Atomic Layer Deposition for Highly Efficient Dopamine Sensing

Abstract

The Fe 2 O 3 nanozyme has been identified as the most promising alternative for the Fe 3 O 4 nanozyme due to its relatively low toxic risk and good chemical stability. However, its enzyme-like activity is relatively low enough to meet specific application requirements. Furthermore, previous synthesis approaches have difficulties in fabricating ultra-small Fe 2 O 3 nanoparticles with tunable size and suffer from agglomeration problems. In this study, atomic layer deposition (ALD) was used to deposit Fe 2 O 3 on surfaces of carbon nanotubes to form hybrid nanozymes (Fe 2 O 3 /CNTs). ALD enables the preparation of ultrafine Fe 2 O 3 nanoparticles with precise size control <1 nm, while CNTs could be served as promising support for good dispersibility and as an effective activity activator. Hence, the formed Fe 2 O 3 /CNTs exhibit excellent peroxidase-like activity with a specific peroxidase activity of 24.5 U mg −1 . A colorimetric method for sensing dopamine (DA) was established and presented good sensitivity with a limit of detection (LOD) as low as 0.11 µM. These results demonstrated that, in virtue of meticulous engineering methods like ALD, carbon nanomaterial-based hybrids can be developed as talented enzyme mimetic, thus paving a way for nanozyme design with desired activity and broadening their applications in biosensing and other fields.

Prospects of nano-carbons as emerging catalysts for enzyme-mimetic applications

“…The peroxidase activity was significantly enhanced in comparison to pristine CNT and Fe 2 O 3 /CNT. 125 Furthermore, Gally et al functionalized CNTs with avidin, which is a protein that binds biotin, and formed a nanocomposite with ruthenium NPS. The synergic effect of the synthesized composites reduced H 2 O 2 efficiently.…”

Novel Nanofluidic Cells Based on Nanowires and Nanotubes for Advanced Chemical and Bio-Sensing Applications

“…The device shows ideal sensing characteristics in sensitivity, linearity and detection limit, which is widely used in flow injection analysis. Furthermore, a construct of Fe 2 O 3 /CNTs hybrid nanozyme has been prepared by ALD for dopamine detection [ 98 ]. CNTs with good activity provide a dispersibility support for the ultra-small nanoparticles (<1 nm) with adjustable size.…”

A novel copper-based nanozyme: fabrication and application for colorimetric detection of resveratrol

“…Since K m is known to be a measure of enzyme affinity for the substrate, achieving low K m and high V max is essential for improving its catalytic efficacy. 38 As shown in Fig. 3, urea@Cu-NF displayed Michaelis–Menten behaviour for both H 2 O 2 and TMB.…”