Jiang Shaojuan, Su Gehong, Wu Jianbing, Song Chang, Lu Zhiwei, Wu Chun, Wang Yanying, Wang Pingrong, He Mingxia, Zhao Ying, Jiang Yuanyuan, Zhao Xiaoqing, Rao Hanbing, Sun Mengmeng
College of Science, Sichuan Agricultural University, Xin Kang Road, Yucheng District, Ya'an 625014, P.R. China.
School of Biological and Chemical Engineering, Panzhihua University, Panzhihua 617000, P.R. China.
ACS Appl Mater Interfaces. 2023 Mar 8;15(9):11787-11801. doi: 10.1021/acsami.2c22136. Epub 2023 Feb 21.
Although the application of nanozymes has been widely studied, it is still a huge challenge to develop highly active and multifunctional nanozyme catalysts with a wider application prospect. CoO/CoFeO hollow nanocubes (HNCs) with oxygen vacancies were proposed in this study, which had a porous oxide heterostructure with CoFeO as the core and CoO as the shell. The CoO/CoFeO HNCs had three enzyme activities: peroxidase-like, oxidase-like, and catalase-like. Combining XPS depth profiling with density functional theory (DFT), the catalytic mechanism of peroxidase-like activity was explored in depth, which was mainly originated from ·OH produced by the synergistic effect between the outer oxygen and inner oxygen and electron transfer between Co and Fe. A colorimetry/smartphone dual sensing platform was designed based on the peroxidase-like activity. Especially, a multifunctional intelligent sensing platform based on deep learning-YOLO v3 algorithm-assisted smartphone was constructed to realize real-time and rapid in situ detection of l-cysteine, norfloxacin, and zearalenone. Surprisingly, the detection limit of norfloxacin was low at 0.015 μM, which was better than that of the newly published detection method in the field of nanozymes. Meanwhile, the detection mechanism of l-cysteine and norfloxacin was successfully investigated by in situ FTIR. In fact, it also showed outstanding applications in detecting l-cysteine in the food environment and norfloxacin in drugs. Furthermore, CoO/CoFeO HNCs also could degrade 99.24% of rhodamine B, along with good reusability even after 10-cycle runs. Therefore, this work provided an in-depth understanding of the synergistic effect between the outer and inner oxygen in the reaction mechanism and an efficient method for establishing a deep-learning-assisted intelligent detection platform. In addition, this research also offered a good guideline for the further development and construction of nanozyme catalysts with multienzyme activities and multifunctional applications.
尽管纳米酶的应用已得到广泛研究，但开发具有更高活性和多功能性、应用前景更广阔的纳米酶催化剂仍是一个巨大挑战。本研究提出了具有氧空位的CoO/CoFeO中空纳米立方体（HNCs），其具有以CoFeO为核、CoO为壳的多孔氧化物异质结构。CoO/CoFeO HNCs具有三种酶活性：类过氧化物酶活性、类氧化酶活性和类过氧化氢酶活性。结合X射线光电子能谱深度剖析和密度泛函理论（DFT），深入探究了类过氧化物酶活性的催化机制，其主要源于外层氧和内层氧之间的协同效应产生的·OH以及Co和Fe之间的电子转移。基于类过氧化物酶活性设计了比色法/智能手机双传感平台。特别是，构建了基于深度学习-YOLO v3算法辅助智能手机的多功能智能传感平台，以实现对l-半胱氨酸、诺氟沙星和玉米赤霉烯酮的实时快速原位检测。令人惊讶的是，诺氟沙星的检测限低至0.015 μM，优于纳米酶领域新发表的检测方法。同时，通过原位傅里叶变换红外光谱成功研究了l-半胱氨酸和诺氟沙星的检测机制。事实上，它在食品环境中检测l-半胱氨酸和药物中检测诺氟沙星方面也显示出出色的应用。此外，CoO/CoFeO HNCs还能降解99.24%的罗丹明B，即使经过10次循环运行仍具有良好的可重复使用性。因此，这项工作深入了解了反应机制中外层氧和内层氧之间的协同效应，并为建立深度学习辅助智能检测平台提供了一种有效方法。此外，本研究还为进一步开发和构建具有多酶活性和多功能应用的纳米酶催化剂提供了良好的指导。
