Enhanced Signal and Quantitative Detection of Anti-Interferon-Gamma Antibody by Using a Nanometer Biolinker

PLoS One. 2016 Jul 26;11(7):e0160031. doi: 10.1371/journal.pone.0160031. eCollection 2016.

Abstract

For rapid screening and quantification of an antisera antibody, a nanometer bithiophene-based conductive biolinker can enhanced signal performance and can be used to verify the interaction of an anti-IFN-γ antibody with an IFN-γ protein. The experimental measurements take a generic approach which takes advantage of the functionality of thiophene-based linkers for biosensors. Effects associated with using bithiophene as a biolinker for surface plasmon resonance (SPR) spectroscopy are examined in this paper. By using an atomic force microscope (AFM), it was observed that the morphology of the bithiophene modified gold sensor surface became smoother than the original gold surface. We compared the response and concentration of the anti-IFN-γ antibody on a bithiophene-coated and dextran-coated biochip as well as on different thickness-modified surfaces under SPR relevant conditions. The results indicate that a response to IFN-γ molecules immobilized on a sensor using a bithiophene biolinker improved more than 8-fold when compared to that of a sensor using a dextran biolinker. Furthermore, the regeneration ability of the sensor surface shows good repeatability as only less than a 1% decrease was found after repeating the experimental work over 6 cycles. The characteristics provided us with a good platform for rapid screening, real-time monitoring and quantitative concentration of the autoimmune antibody activities.

MeSH terms

  • Animals
  • Antibodies / analysis
  • Antibodies / immunology*
  • Biosensing Techniques / methods*
  • Dextrans / chemistry
  • Gold / chemistry
  • Humans
  • Immobilized Proteins / immunology
  • Interferon-gamma / immunology*
  • Mice
  • Nanotechnology / methods*
  • Sensitivity and Specificity
  • Thiophenes / chemistry

Substances

  • Antibodies
  • Dextrans
  • Immobilized Proteins
  • Thiophenes
  • Gold
  • Interferon-gamma

Grants and funding

This work was supported by Taiwan’s Ministry of Science & Technology under Contract No. NSC 100-2627-E-002-001, NSC 101-2627-E-002-00, NSC 102-2627-E-002-004, and NSC 102-2221-E-002-188-MY3 (https://www.most.gov.tw/en/public); and Taiwan’s Ministry of Science & Technology under Contract No. NSC 100-2627-E-002-001, NSC 101-2627-E-002-00, NSC 102-2627-E-002-004, and NSC 102-2221-E-002-188-MY3 (https://www.most.gov.tw/en/public). The authors acknowledge the 408 Technology Commons, College of Life Science, National Taiwan University for the SPR support. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.