title: CeO2nanocrystallines ensemble-on-nitrogen-doped graphene nanocomposites: one-pot, rapid synthesis and excellent electrocatalytic activity for enzymatic biosensing.
abstract: Ceria nanomaterials for heterogeneous catalysis have attracted much attention due to their excellent properties and have been extensively applied in recent years. But the poor electron conductivity and the aggregation behavior severely affect their electrocatalytic performances. In this paper, we prepared a novel catalyst based on CeO2nanocrystallines (CeO2NCs) ensemble-on-nitrogen-doped graphene (CeO2-NG) nanocomposites through a one-step heat-treatment without the need of the precursor. The results confirmed that the high dispersion of CeO2NCs with the uniform size distribution of about 5nm on the surface of nitrogen-doped graphene (NG) sheets could be easily obtained via the one-step procedure and the resultant CeO2-NG nanocomposites were an excellent electrode material possessing outstanding electrochemical features for electron transfer. Luminol, an important electroactive substance, was further chosen to inspect the electrocatalytic properties of the as-prepared CeO2-NG nanocomposites. The studies showed that the presence of the NG in CeO2-NG nanocomposites could facilitate the electrochemical redox process of luminol. Compared with pristine CeO2NCs, the synthesized CeO2-NG nanocomposites can enhance the electrochemiluminescence (ECL) intensity by 3.3-fold and decrease the onset ECL potential for about 72mV in the neutral condition. Employing above superiority, selecting cholesterol oxidase (ChOx) as the model oxidase, a facile ECL method for cholesterol detection with the CeO2-NG nanocomposites as the matrix to immobilize enzyme ChOx was developed. The results demonstrated CeO2-NG nanocomposites exhibited excellent performances in terms of sensitivity and catalytic activities, indicating that NG-based nanomaterials have great promise in electrocatalytic and enzymatic biosensing fields.
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Xiaojiao
authors.initials: X
authors.lastname: Du
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Ding
authors.initials: D
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Saibo
authors.initials: S
authors.lastname: Chen
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Liming
authors.initials: L
authors.lastname: Dai
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Hao
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Tianyou
authors.initials: T
authors.lastname: You
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China.
authors.forename: Hanping
authors.initials: H
authors.lastname: Mao
authors.affiliation: Key Laboratory of Modern Agriculture Equipment and Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China. Electronic address: wangkun@ujs.edu.cn.
authors.forename: Kun
authors.initials: K
authors.lastname: Wang
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D002563:Cerium / Q000737:chemistry*; D002784:Cholesterol / Q000032:analysis* / Q000097:blood*; D002789:Cholesterol Oxidase / Q000737:chemistry; D055664:Electrochemical Techniques / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D049408:Luminescent Agents / Q000737:chemistry; D008163:Luminescent Measurements / Q000379:methods; D008165:Luminol / Q000737:chemistry; D008892:Milk / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D053758:Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods; D009584:Nitrogen / Q000737:chemistry
chemical_list: D004800:Enzymes, Immobilized; D049408:Luminescent Agents; D002563:Cerium; D008165:Luminol; C030583:ceric oxide; D006108:Graphite; D002784:Cholesterol; D002789:Cholesterol Oxidase; D009584:Nitrogen
keywords: Biosensor; CeO(2) nanocrystallines; Enzyme; Nitrogen-doped graphene