Journal of Zhejiang University SCIENCE B

, Volume 9, Issue 2, pp 121–131

Sensing Escherichia coli O157:H7 via frequency shift through a self-assembled monolayer based QCM immunosensor

Authors

  • Li-jiang Wang
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
  • Chun-sheng Wu
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
  • Zhao-ying Hu
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
  • Yuan-fan Zhang
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
  • Rong Li
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
    • Biosensor National Special Laboratory, Key Laboratory of Biomedical Engineering of Ministry of Education, Department of Biomedical EngineeringZhejiang University
Article

DOI: 10.1631/jzus.B0710307

Cite this article as:
Wang, L., Wu, C., Hu, Z. et al. J. Zhejiang Univ. Sci. B (2008) 9: 121. doi:10.1631/jzus.B0710307

Abstract

By means of the specific immuno-recognition and ultra-sensitive mass detection, a quartz crystal microbalance (QCM) biosensor for Escherichia coli O157:H7 detection was developed in this work. As a suitable surfactant, 16-mercaptohexadecanoic acid (MHDA) was introduced onto the Au surface of QCM, and then self-assembled with N-hydroxysuccinimide (NHS) raster as a reactive intermediate to provide an active interface for the specific antibody immobilization. The binding of target bacteria with the immobilized antibodies decreased the sensor’s resonant frequency, and the frequency shift was correlated to the bacterial concentration. The stepwise assembly of the immunosensor was characterized by means of the electrochemical techniques. Using the immersion-dry-immersion procedure, this QCM biosensor could detect 2.0×102 colony forming units (CFU)/ml E. coli O157:H7. In order to reduce the fabrication time, a polyelectrolyte layer-by-layer self-assembly (LBL-SA) method was adopted for fast construction. Finally, the reproducibility of this biosensor was discussed.

Key words

BiosensorEscherichia coli O157:H7ImmunosensorLayer-by-layer self-assembly (LBL-SA)Quartz crystal microbalance (QCM)

Document code

A

CLC number

Q81
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Copyright information

© Springer-Verlag 2008