Signal Amplification by Enzymatic Reaction in an Immunosensor Based on Localized Surface Plasmon Resonance (LSPR)

Sensors

Tae-Han Lee¹  Seung-Woo Lee¹  Ji-Ae Jung¹  Junhyoung Ahn¹  Min-Gon Kim¹ 

[1] Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 305-806, Korea; E-Mail:

关键词: immunosensor;    localized surface plasmon resonance (LSPR);    gold nano-island;    enzyme-catalyzed precipitation;   

DOI  :  10.3390/s100302045

来源: mdpi

【 摘 要 】

An enzymatic reaction was employed as a means to enhance the sensitivity of an immunosensor based on localized surface plasmon resonance (LSPR). The reaction occurs after intermolecular binding between an antigen and an antibody on gold nano-island (NI) surfaces. For LSPR sensing, the gold NI surface was fabricated on glass substrates using vacuum evaporation and heat treatment. The interferon-γ (IFN-γ) capture antibody was immobilized on the gold NIs, followed by binding of IFN-γ to the antibody. Subsequently, a biotinylated antibody and a horseradish peroxidase (HRP) conjugated with avidin were simultaneously introduced. A solution of 4-chloro-1-naphthol (4-CN) was then used for precipitation; precipitation was the result of the enzymatic reaction catalyzed the HRP on gold NIs. The LSPR spectra were obtained after each binding process. Using this method, the enzyme-catalyzed precipitation reaction on the gold NI surface was found to effectively amplify the change in the signal of the LSPR immunosensor after intermolecular binding.

【 授权许可】

CC BY   
© 2010 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.