Next Article in Journal
Application of Surface Protective Coating to Enhance Environment-Withstanding Property of the MEMS 2D Wind Direction and Wind Speed Sensor
Next Article in Special Issue
Sensitive Genotyping of Foodborne-Associated Human Noroviruses and Hepatitis A Virus Using an Array-Based Platform
Previous Article in Journal
Using Impedance Measurements to Characterize Surface Modified with Gold Nanoparticles
Previous Article in Special Issue
Multifunctional Nanotechnology-Enabled Sensors for Rapid Capture and Detection of Pathogens
Article Menu
Issue 9 (September) cover image

Export Article

Open AccessArticle
Sensors 2017, 17(9), 2145; https://doi.org/10.3390/s17092145

Repetitive Immunosensor with a Fiber-Optic Device and Antibody-Coated Magnetic Beads for Semi-Continuous Monitoring of Escherichia coli O157:H7

1
Department of Biomedical Devices and Instrumentation, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan
2
Department of Mechanical Engineering, Tokyo National College of Technology, 1220-1, Kunugida-machi, Hachioji-shi, Tokyo 193-0997, Japan
*
Author to whom correspondence should be addressed.
Received: 31 July 2017 / Revised: 12 September 2017 / Accepted: 15 September 2017 / Published: 19 September 2017
(This article belongs to the Special Issue Sensors for Toxic and Pathogen Detection)
View Full-Text   |   Download PDF [7756 KB, uploaded 19 September 2017]   |  

Abstract

A rapid and reproducible fiber-optic immunosensor for Escherichia coli O157:H7 (E. coli O157:H7) was described. The biosensor consisted of a flow cell, an optical fiber with a thin Ni layer, and a PC linked fluorometer. First, the samples with E. coli O157:H7 were incubated with magnetic beads coated with anti-E. coli O157:H7 antibodies and anti-E. coli O157:H7 antibodies labeled cyanine 5 (Cy5) to make sandwich complexes. Then the Cy5-(E. coli O157:H7)-beads were injected into a flow cell and pulled to the magnetized Ni layer on the optical fiber set in the flow cell. An excitation light (λ = 635 nm) was used to illuminate the optical fiber, and the Cy5 florescent molecules facing the optical fiber were exposed to an evanescent wave from the optical fiber. The 670 nm fluorescent light was measured using a photodiode. Finally, the magnetic intensity of the Ni layer was removed and the Cy5-E. coli O157:H7-beads were washed out for the next immunoassay. E. coli O157:H7, diluted with phosphate buffer (PB), was measured from 1 × 105 to 1 × 107 cells/mL. The total time required for an assay was less than 15 min (except for the pretreatment process) and repeating immunoassay on one optical fiber was made possible. View Full-Text
Keywords: fiber-optics; fluorescence; evanescent wave; immunosensor; antigen-antibody complex; E. coli; magnetic beads fiber-optics; fluorescence; evanescent wave; immunosensor; antigen-antibody complex; E. coli; magnetic beads
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Taniguchi, M.; Saito, H.; Mitsubayashi, K. Repetitive Immunosensor with a Fiber-Optic Device and Antibody-Coated Magnetic Beads for Semi-Continuous Monitoring of Escherichia coli O157:H7. Sensors 2017, 17, 2145.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top