Nanogold-actuated biomimetic peroxidase for sensitized electrochemical immunoassay of carcinoembryonic antigen in human serum

• Published in: Analytica chimica acta Vol. 678; no. 2; pp. 169 - 175
• Main Authors: Chen, Huafeng, Tang, Juan, Su, Biling, Chen, Guonan, Huang, Jianxin, Tang, Dianping
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30.09.2010; Elsevier
• Subjects: Analytical chemistry; Antigens; Biomimetic peroxidase; Carcinoembryonic antigen; Carcinoembryonic Antigen - blood; Carcinoembryonic Antigen - immunology; Chemistry; Electrochemical immunosensor; Electrochemical methods; Electrochemical Techniques - methods; Enzymes, Immobilized; Exact sciences and technology; Fe 3O 4 nanoparticles; Ferrosoferric Oxide - chemistry; General, instrumentation; Gold - chemistry; Horseradish Peroxidase - chemistry; Horseradish Peroxidase - immunology; Human; Humans; Immunoassay; Immunoassay - methods; Immunosensors; Limit of Detection; Miscellaneous; Nanocomposites; Nanogold particles; Nanomaterials; Nanoparticles - chemistry; Nanostructure; Prussian blue; Reproducibility of Results; Serums; Carcinoembryonic antigen; Electrochemical immunosensor; Nanogold particles; Prussian blue; Biomimetic peroxidase; Fe 3O 4 nanoparticles; Chemical analysis; Dyes; Hexacyanoferrates; Electrochemical method; Nanoparticle; Immobilization; Immunosensor; Immunological method; Electrochemicalimmunosensor; Improvement; Reduction; nanoparticles; Dynamics; Detection limit; Membrane; Serum; Peroxidase; Polyion; Inhibition; Variation coefficient; Fe; Human; Enzyme; Antibody; Ultratrace compound; Chemical sensor; Antigen; 0; Sensitivity; Peroxidases; Biosensor; Automatic analyzer; Oxidoreductases
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2010.09.003

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 3O 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 2O 2. Nanogold-actuated nano-Fe 3O 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 3 σ). 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.