Regular Article

Theoretical evaluation of a fiber-optic SPR biosensor based on a gold layer treated with thiol acid

¹ Research Unit of Quantum Physics 11 ES 54, Faculty of Science of Monastir, University of Monastir, Environment Boulevard, Monastir 5019, Tunisia
² Department of Radiological Sciences and Medical Imaging, College of Applied Medical Sciences, Majmaah University, Majmaah 11952, Saudi Arabia
³ Laboratory of Electronics and Microelectronics, Faculty of Science of Monastir, University of Monastir, Environment Boulevard, Monastir 5019, Tunisia

^* e-mail: yosra_saad@yahoo.com

Received: 6 February 2018
Received in final form: 27 June 2018
Accepted: 29 June 2018
Published online: 10 October 2018

Abstract

In the present work, we have investigated the surface plasmons resonance (SPR) biosensor based on optical fiber applied for the detection of pathogenic bacteria (Escherichia coli), in order to overcome the stresses caused by the massive prism and to obtain a reliable and efficient miniature device. The modeling procedure is based on a matrix formalism developed for the optical studies of multilayer media. We have tested the response of the fiber optic biosensor based on a golden substrate functionalized with thiol acid. The results show that the SPR biosensor sensitivity is improved by treating the gold electrode with thiol. An improved SPR biosensor with a high resolution is obtained.