Disposable electrochemical immunosensor based on peroxidase-like magnetic silica–graphene oxide composites for detection of cancer antigen 153

• DOI: 10.1016/j.snb.2013.10.127
• Publication Date: 2013-11-07T22:46:04Z
• Authors: Shenguang Ge; Mingwei Sun; Weiyan Liu; Shuai Li; Xiu Wang; Chengchao Chu; Mei Yan; Jinghua Yu
• Keywords: 01 natural sciences; 3. Good health; 0104 chemical sciences

Abstract A disposable electrochemical immunosensor was established for the detection of cancer antigen 153 (CA 153) using peroxidase-like magnetic silica nanoparticles/graphene oxide composites as labels and graphene oxide modified screen-printed carbon electrodes. The magnetic silica nanoparticles/graphene oxide composites were prepared via conjugating azide-functionalized magnetic silica nanoparticles to acetylene-functionalized graphene oxide by click chemistry with a copper-catalyzed 1,3-dipolar cycloaddition reaction. Structure characterization was obtained by means of atomic force microscope, X-ray diffraction and transmission electron microscope. The magnetic silica nanoparticles/graphene oxide composites showed great peroxidase-like activity. The CA 153 immunosensor was fabricated with sandwich method by immobilizing a monoclonal anti-CA 153 antibody on the graphene oxide attached on a screen-printed electrode, peroxidase-like magnetic silica nanoparticles/graphene oxide composites was used as signal label. This method was simple, inexpensive, highly sensitive, and selective for CA 153 detection with a proportional to the logarithm value of the CA 153 concentration from 10 −3 to 200 U/mL and the detection limit of 2.8 × 10 −4 U/mL. In addition, the assay was evaluated with CA 153 spiked serum samples and commercially available Electrochemiluminescent Analyzer obtained excellent correlation.