Facile synthesis of magnetic hierarchical flower-like Co3O4 spheres: Mechanism, excellent tetra-enzyme mimics and their colorimetric biosensing applications
Facile synthesis of magnetic hierarchical flower-like Co3O4 spheres: Mechanism, excellent tetra-enzyme mimics and their colorimetric biosensing applications
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DOI：
10.1016/j.bios.2020.112342
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发表时间：
2020-10-01
影响因子：
12.6
通讯作者：
Liu, Aihua
中科院分区：
文献类型：
--
作者：
Liu, Xuan;Yan, Lu;Liu, Aihua
采用无模板、无表面活性剂的湿化学方法，在室温下一步合成了磁性分级花状Co 3 O 4微球（Co 3 O 4纳米花）。探讨了Co 3 O 4纳米花的形成机理。所制备的Co 3 O 4纳米花具有良好的四酶模拟活性，包括类氧化酶、类过氧化物酶、类过氧化氢酶和类超氧化物歧化酶（SOD）活性。研究了Co 3 O 4纳米花的催化机理。Co 3 O 4纳米花的类氧化酶催化活性来源于Co 3 O 4本身固有的氧空位，而类过氧化物酶催化活性来源于过氧化氢（H2 O2）产生的中心点OH自由基。通过改变pH值、添加适当的清除剂或选择其特异性底物来特异性地抑制其他纳米酶，可以获得与Co 3 O 4纳米花的仅一种特异性酶模拟反应。此外，稳态动力学和催化性能的氧化酶，过氧化物酶和过氧化氢酶模拟Co 3 O 4纳米花进行了研究。基于Co 3 O 4纳米花的类氧化酶和类过氧化物酶活性，构建了双功能比色传感平台，用于酸性磷酸酶（ACP）和H2 O2的灵敏检测，线性范围分别为0.1-25 μ L-1和4-400 μ M.此外，它能够检测血清样品中的ACP和水样中的H2 O2，分别。因此，四酶模拟Co 3 O 4纳米花在生物传感器、肿瘤治疗、环境监测和生物催化等领域显示出广阔的应用前景。
Magnetic hierarchical flower-like Co3O4 spheres (Co3O4 nanoflowers) were facilely prepared via one-step surfactant-free and template-free wet chemical route at room temperature. The formation mechanism of Co3O4 nanoflowers was explored. The as-prepared Co3O4 nanoflowers exhibited excellent tetra-enzyme mimetic activities, including oxidase-like, peroxidase-like, catalase-like and superoxide dismutase (SOD)-like activity. The catalytic mechanism of the Co3O4 nanoflowers was studied in detail. The oxidase-like catalytic activity of Co3O4 nanoflowers was derived from the inherent oxygen vacancies of Co3O4, while the peroxidase-like catalytic activity originated from the center dot OH radical generated by hydrogen peroxide (H2O2). Only one specific enzyme mimics reaction with Co3O4 nanoflowers can be obtained by inhibiting specifically other nanozymes via varying pH, adding appropriate scavengers or selecting its specific substrate. Further, the steady-state kinetic and catalytic performance of the oxidase-, peroxidase- and catalase mimics of Co3O4 nanoflowers were studied. Based on the oxidase-like and peroxidase-like activities of Co3O4 nanoflowers, bifunctional colorimetric sensing platforms were constructed for the sensitive detection of acid phosphatase (ACP) with the linear range of 0.1-25 U L-1 and H2O2 with the linear range of 4-400 mu M. Further, it is capable of detecting ACP in serum samples and H2O2 in water samples, respectively. Thus, the tetra-enzyme mimetic Co3O4 nanoflowers show broad prospects in the fields of biosensors, tumor therapy, environmental monitoring and biocatalysis.