Back to Journals » International Journal of Nanomedicine » Volume 10 » Special Issue on diverse applications in Nano-Theranostics

Enhanced detection sensitivity of Escherichia coli O157:H7 using surface-modified gold nanorods

Authors Ramasamy M, Yi DK, An SSA

Received 11 May 2015

Accepted for publication 8 July 2015

Published 27 August 2015 Volume 2015:10(Special Issue on diverse applications in Nano-Theranostics) Pages 179—190

DOI https://doi.org/10.2147/IJN.S88379

Checked for plagiarism Yes

Review by Single-blind

Peer reviewers approved by Dr Govarthanan Muthusamy

Peer reviewer comments 3

Editor who approved publication: Prof. Dr. Thomas J Webster


Mohankandhasamy Ramasamy,1 Dong Kee Yi,2,3 Seong Soo A An4

1School of Chemical Engineering, Yeungnam University, Gyeongsan, 2Department of Chemistry, 3Department of Energy and Biotechnology, Myongji University, Yongin, 4Department of BioNano Technology, Gachon University, Seongnam, Republic of Korea


Abstract: Escherichia coli O157:H7 (O157) is a Gram negative and highly virulent bacteria found in food and water sources, and is a leading cause of chronic diseases worldwide. Diagnosis and prevention from the infection require simple and rapid analysis methods for the detection of pathogens, including O157. Endogenous membrane peroxidase, an enzyme present on the surface of O157, was used for the colorimetric detection of bacteria by catalytic oxidation of the peroxidase substrate. In this study, we have analyzed the impact of the synthesized bare gold nanorods (AuNRs) and silica-coated AuNRs on the growth of E. coli O157. Along with the membrane peroxidase activity of O157, other bacteria strains were analyzed. Different concentrations of nanorods were used to analyze the growth responses, enzymatic changes, and morphological alterations of bacteria by measuring optical density, 3,3',5,5'-tetramethylbenzidine assay, flow cytometry analysis, and microscopy studies. The results revealed that O157 showed higher and continuous membrane peroxidase activity than other bacteria. Furthermore, O157 treated with bare AuNRs showed a decreased growth rate in comparison with the bacteria with surface modified AuNRs. Interestingly, silica-coated AuNRs favored the growth of bacteria and also increased membrane peroxidase activity. This result can be particularly important for the enzymatic analysis of surface treated AuNRs in various microbiological applicants.

Keywords: E. coli, O157:H7, endogenous membrane peroxidase, gold nanorod, silica-coated gold nanorod

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]