title: Nanogold-actuated biomimetic peroxidase for sensitized electrochemical immunoassay of carcinoembryonic antigen in human serum.
abstract: A new electrochemical immunoassay protocol for the determination of carcinoembryonic antigen (CEA) in human serum was developed by means of immobilizing horseradish peroxidase-labeled anti-CEA antibodies (HRP-anti-CEA) on the nanogold/nano-Fe(3)O(4) particles-functionalized polyion complex (PIC) membrane. With a one-step immunoassay format, the formed immunocomplex inhibited partly the bioactive center of the immobilized HRP, and decreased the HRP toward the reduction of H(2)O(2). Nanogold-actuated nano-Fe(3)O(4) mimetic peroxidase was used for the sensitivity improvement of the electrochemical immunosensor with Prussian blue (PB) as mediators. Under optimal conditions, the electrochemical immunosensor displayed a wide dynamic range of 0.1-220 ng mL(-1) with a relative low detection limit (LOD) of 10 pg mL(-1) CEA (at 3σ). Intra- and inter-assay show good precisions with a coefficient of variation (CV) lower than 7.8% and 7.3%, respectively. No significant difference at the 95% confidence level was encountered in the analysis of 17 human serum specimens between the electrochemical immunosensor and automatic electrochemiluminescent (ECL) analyzer for the determination of CEA.
authors.affiliation: Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, and Fujian Provincial Key Laboratory of Analysis and Detection for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China.
authors.forename: Huafeng
authors.initials: H
authors.lastname: Chen
authors.forename: Juan
authors.initials: J
authors.lastname: Tang
authors.forename: Biling
authors.initials: B
authors.lastname: Su
authors.forename: Guonan
authors.initials: G
authors.lastname: Chen
authors.forename: Jianxin
authors.initials: J
authors.lastname: Huang
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
mesh_terms: D002272:Carcinoembryonic Antigen / Q000097:blood* / Q000276:immunology; D055664:Electrochemical Techniques / Q000379:methods*; D004800:Enzymes, Immobilized; D052203:Ferrosoferric Oxide / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000276:immunology; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D002272:Carcinoembryonic Antigen; D004800:Enzymes, Immobilized; D006046:Gold; D006735:Horseradish Peroxidase; D052203:Ferrosoferric Oxide