Gold Nanoparticle–Colloidal Carbon Nanosphere Hybrid Material: Preparation, Characterization, and Application for an Amplified Electrochemical Immunoassay

Authors

  • Rongjing Cui,

    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    Search for more papers by this author
  • Chang Liu,

    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    Search for more papers by this author
  • Jianming Shen,

    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    Search for more papers by this author
  • Di Gao,

    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    Search for more papers by this author
  • Jun-Jie Zhu,

    Corresponding author
    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    • MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China).
    Search for more papers by this author
  • Hong-Yuan Chen

    1. MOE Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (P. R. China)
    Search for more papers by this author

  • This project was supported by the National Natural Science Foundation of China (20635020, 20575026, and 20521503) and the National Basic Research Program of China (2006CB933201). We are grateful to the financial support of the European Community Sixth Framework Program through a STREP grant to the SELECTNANO Consortium, Contract No. 516922.

Abstract

A rapid microwave-hydrothermal method has been developed to prepare monodisperse colloidal carbon nanospheres from glucose solution, and gold nanoparticles (AuNPs) are successfully assembled on the surface of the colloidal carbon nanospheres by a self-assembly approach. The resulting AuNP/colloidal carbon nanosphere hybrid material (AuNP/C) has been characterized and is expected to offer a promising template for biomolecule immobilization and biosensor fabrication because of its satisfactory chemical stability and the good biocompatibility of AuNPs. Herein, as an example, it is demonstrated that the as-prepared AuNP/C hybrid material can be conjugated with horseradish peroxidase-labeled antibody (HRP-Ab2) to fabricate HRP-Ab2-AuNP/C bioconjugates, which can then be used as a label for the sensitive detection of protein. The amperometric immunosensor fabricated on a carbon nanotube-modified glass carbon electrode was very effective for antibody immobilization. The approach provided a linear response range between 0.01 and 250 ng mL−1 with a detection limit of 5.6 pg mL−1. The developed assay method was versatile, offered enhanced performances, and could be easily extended to other protein detection as well as DNA analysis.

Ancillary