Yang Yingchun, Li Tao, Qin Yong, Zhang Lianbing, Chen Yao
School of Life Sciences, Northwestern Polytechnical University, Xi'an, China.
Front Chem. 2020 Oct 21;8:564968. doi: 10.3389/fchem.2020.564968. eCollection 2020.
The FeO nanozyme has been identified as the most promising alternative for the FeO 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 FeO nanoparticles with tunable size and suffer from agglomeration problems. In this study, atomic layer deposition (ALD) was used to deposit FeO on surfaces of carbon nanotubes to form hybrid nanozymes (FeO/CNTs). ALD enables the preparation of ultrafine FeO 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 FeO/CNTs exhibit excellent peroxidase-like activity with a specific peroxidase activity of 24.5 U mg. 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.
由于其相对较低的毒性风险和良好的化学稳定性，FeO纳米酶已被确定为最有前途的替代物。然而，其类酶活性相对较低，不足以满足特定的应用要求。此外，以前的合成方法在制备尺寸可调的超小FeO纳米颗粒方面存在困难，并且存在团聚问题。在本研究中，采用原子层沉积（ALD）法将FeO沉积在碳纳米管表面，形成杂化纳米酶（FeO/CNTs）。ALD能够制备尺寸精确控制在<1 nm的超细FeO纳米颗粒，而碳纳米管可作为具有良好分散性的理想载体和有效的活性激活剂。因此，形成的FeO/CNTs表现出优异的过氧化物酶样活性，比过氧化物酶活性为24.5 U mg。建立了一种检测多巴胺（DA）的比色法，具有良好的灵敏度，检测限（LOD）低至0.11 μM。这些结果表明，借助ALD等精细的工程方法，基于碳纳米材料的杂化物可以被开发成为有才华的酶模拟物，从而为具有所需活性的纳米酶设计铺平道路，并拓宽其在生物传感和其他领域的应用。
