title: Coral-like CeO2/NiO nanocomposites with efficient enzyme-mimetic activity for biosensing application.
abstract: Development of nanomaterials-based enzymatic mimics has gained considerable attention in recent years, because of their low cost, high stability and efficiently catalytic ability. Here, CeO2was successfully incorporated into the coral-like NiO nanostructures assembled by nanoflakes with high surface area, forming the coral-like CeO2/NiO nanocomposites. The morphology and composition of CeO2/NiO nanocomposites were characterized by XRD, SEM, element mapping and XPS. The results of characterization showed that cerium was highly dispersed in the coral-like NiO nanostructures. The peroxidase-like activity of CeO2/NiO nanocomposites was investigated, and they exhibited enhanced peroxidase-like activity in comparison to that of pure NiO or CeO2. The catalytic activity was dependent on the cerium content, and the optimal content was 2.5%. The enhanced catalytic activity of CeO2/NiO nanocomposites arised from their high ability of electron transfer because of cerium incorporation. The catalytic performance of CeO2/NiO nanocomposites was evaluated by steady-state kinetic, which showed that the CeO2/NiO nanocomposites exhibited higher affinity for the substrates and similar catalytic efficiency compared with natural peroxidase. Based on the efficient peroxidase-like activity, CeO2/NiO was used for H2O2determination. The constructed colorimetric H2O2sensor had fast response for only 5min, a wide linear range from 0.05 to 40mM and a low detection limit with 0.88μM. The CeO2/NiO nanocomposites were expected to have potential applications in clinical diagnosis and biotechnology as enzymatic mimics.
authors.affiliation: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, PR China.
authors.forename: Jianshuai
authors.initials: J
authors.lastname: Mu
authors.affiliation: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.affiliation: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, PR China. Electronic address: encui_yang@163.com.
authors.forename: En-Cui
authors.initials: EC
authors.lastname: Yang
authors.affiliation: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University, Tianjin 300387, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300071, China. Electronic address: xiaojun_zhao15@163.com.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Zhao
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000737:chemistry; D015374:Biosensing Techniques; D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D058266:Dielectric Spectroscopy; D055664:Electrochemical Techniques; D004566:Electrodes; D006861:Hydrogen Peroxide / Q000032:analysis*; D057230:Limit of Detection; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D009195:Peroxidase / Q000737:chemistry / Q000378:metabolism; D014961:X-Ray Diffraction
chemical_list: D002563:Cerium; C030583:ceric oxide; D009532:Nickel; D006861:Hydrogen Peroxide; C028007:nickel monoxide; D009195:Peroxidase
keywords: Coral-like CeO(2)/NiO; H(2)O(2) sensor; Nanocomposites; Peroxidase-like activity