Next Article in Journal
Hydrodynamic Analysis-Based Modeling and Experimental Verification of a New Water-Jet Thruster for an Amphibious Spherical Robot
Previous Article in Journal
CMTN-SP: A Novel Coverage-Control Algorithm for Moving-Target Nodes Based on Sensing Probability Model in Sensor Networks
Previous Article in Special Issue
Digital, Rapid, Accurate, and Label-Free Enumeration of Viable Microorganisms Enabled by Custom-Built On-Glass-Slide Culturing Device and Microscopic Scanning
Article Menu
Issue 2 (January-2) cover image

Export Article

Open AccessArticle
Sensors 2019, 19(2), 258; https://doi.org/10.3390/s19020258

Label-Free Capacitive Biosensor for Detection of Cryptosporidium

1
School of Engineering, University of British Columbia, 333 University Way, Kelowna, BC V1V 1V7, Canada
2
Department of Mechanical & Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada
*
Author to whom correspondence should be addressed.
Received: 6 November 2018 / Revised: 3 January 2019 / Accepted: 4 January 2019 / Published: 10 January 2019
(This article belongs to the Special Issue Label-Free Biosensors)
Full-Text   |   PDF [2108 KB, uploaded 17 January 2019]   |  

Abstract

Cryptosporidium, an intestinal protozoan pathogen, is one of the leading causes of diarrhea in healthy adults and death in children. Detection of Cryptosporidium oocysts has become a high priority to prevent potential outbreaks. In this paper, a label-free interdigitated-based capacitive biosensor has been introduced for the detection of Cryptosporidium oocysts in water samples. Specific anti-Cryptosporidium monoclonal antibodies (IgG3) were covalently immobilized onto interdigitated gold electrodes as the capture probes, and bovine serum albumin was used to avoid non-specific adsorption. The immobilization of the antibodies was confirmed by measuring the change in the contact angle. The detection was achieved by measuring the relative change in the capacitive/dielectric properties due to the formation of Cryptosporidium-antibody complex. The biosensor has been tested for different concentrations of Cryptosporidium. The results show that the biosensor developed can accurately distinguish different numbers of captured cells and densities on the surface of the biosensor. The number of Cryptosporidium oocysts captured on the electrode surface was confirmed using a fluorescein isothiocyanate (FITC) immunofluorescence assay. The response from the developed biosensor has been mainly dependent on the concentration of Cryptosporidium under optimized conditions. The biosensor showed a linear detection range between 15 and 153 cells/mm2 and a detection limit of 40 cells/mm2. The label-free capacitive biosensor developed has a great potential for detecting Cryptosporidium in environmental water samples. Furthermore, under optimized conditions, this label-free biosensor can be extended for detection of other biomarkers for biomedical and environmental analyses. View Full-Text
Keywords: Cryptosporidium detection; interdigital capacitance transducer; biosensor; label-free detection; electrodes fabrication; immobilization and surface chemistry; capacitive Immunosensor Cryptosporidium detection; interdigital capacitance transducer; biosensor; label-free detection; electrodes fabrication; immobilization and surface chemistry; capacitive Immunosensor
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).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Luka, G.; Samiei, E.; Dehghani, S.; Johnson, T.; Najjaran, H.; Hoorfar, M. Label-Free Capacitive Biosensor for Detection of Cryptosporidium. Sensors 2019, 19, 258.

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