title: Cerium oxide-triggered 'one-to-many' catalytic cycling strategy for in situ amplified electronic signal of low-abundance protein.
abstract: Multifunctionalized thionine-modified cerium oxide (Thi-CeO2) nanostructures with redox ability and catalytic activity were designed as the bionanolabels for in situ amplified electronic signal of low-abundance protein (carcinoembryonic antigen, CEA, used as a model) based on a cerium oxide-triggered 'one-to-many' catalytic cycling strategy. Initially, the carried CeO2 nanoparticles autocatalytically hydrolyzed the phosphate ester bond of l-ascorbic acid 2-phosphate (AAP) to produce a new reactant (l-ascorbic acid, AA), then the generated AA was electrochemically oxidized by the assembled thionine on the Thi-CeO2, and the resultant product was then reduced back to AA by the added tris(2-carboxyethy)phosphine (TCEP). The catalytic cycling could be re-triggered by the thionine and TCEP, resulting in amplification of the electrochemical signal. Under the optimized conditions, the electrochemical immunosensor exhibited a wide linear range of 0.1 pg mL(-1) to 80 ng mL(-1) with a low detection limit of 0.08 pg mL(-1) CEA at the 3σblank level. In addition, the methodology was evaluated for the analysis of clinical serum samples, and was in good accordance with values obtained using the commercialized enzyme-linked immunosorbent assay (ELISA) method.
authors.affiliation: Ministry of Education & Fujian Provincial Key Laboratory of Analysis and Detection of Food Safety, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Tang
authors.forename: Xian
authors.initials: X
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Qunfang
authors.initials: Q
authors.lastname: Li
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
mesh_terms: D000818:Animals; D002384:Catalysis; D002417:Cattle; D002563:Cerium / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D053768:Metal Nanoparticles / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000032:analysis*
chemical_list: D012710:Serum Albumin, Bovine; D002563:Cerium; C030583:ceric oxide