A PDMS microfluidic impedance immunosensor for E. coli O157:H7 and Staphylococcus aureus detection via antibody-immobilized nanoporous membrane

Fei Tan, Hang Mei Polly Leung, Zong Bin Liu, Yu Zhang, Lidan Xiao, Weiwei Ye, Xin Zhang, Li Yi, Mo Yang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

109 Citations (Scopus)

Abstract

In this article, a PDMS microfluidic immunosensor integrated with specific antibody immobilized alumina nanoporous membrane was developed for rapid detection of foodborne pathogens Escherichia coli O157:H7 and Staphylococcus aureus with electrochemical impedance spectrum. Firstly, antibodies to the targeted bacteria were covalently immobilized on the nanoporous alumina membranes via self assembled (3-glycidoxypropyl)trimethoxysilane (GPMS) silane. Then, the impedance spectrum was recorded for bacteria detection ranging from 1 Hz to 100 kHz. The maximum impedance amplitude change for these two food pathogens was around 100 Hz. This microfluidic immunosensor based on nanoporous membrane impedance spectrum could achieve rapid bacteria detection within 2 h with a high sensitivity of 102CFU/ml. Cross-bacteria experiments for E. coli O157:H7 and S. aureus were also explored to testify the specificity. The results showed that impedance amplitude at 100 Hz had a significant reduction in binding of bacteria when the membrane was exposed to non-specific bacteria.
Original languageEnglish
Pages (from-to)328-335
Number of pages8
JournalSensors and Actuators, B: Chemical
Volume159
Issue number1
DOIs
Publication statusPublished - 28 Nov 2011

Keywords

  • Antibody immobilization
  • Bacteria detection
  • Electrochemical impedance spectrum
  • Microfluidic immunosensor
  • Nanoporous membrane

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Instrumentation
  • Condensed Matter Physics
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Electrical and Electronic Engineering
  • Materials Chemistry

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