A naphthoquinone/SAM-mediated biosensor for olive oil polyphenol content.

Authors :: Hammami A
Kuliček J
Raouafi N
Source :: Food chemistry [Food Chem] 2016 Oct 15; Vol. 209, pp. 274-8. Date of Electronic Publication: 2016 Apr 19.
Publication Year :: 2016
Abstract: We report on the design of an amperometric tyrosinase-based biosensor using a self-assembled monolayer of ω-mercaptopropyl naphthoquinone on gold electrode as an electron mediator. Under optimal conditions (i.e. pH=7.4 and E=-0.35V vs. KCl), the chronoamperometric response of the naphthoquinone-modified bioelectrode to successive additions of phenol was evaluated. The biosensor exhibits sensitive bioelectrocatalytic response at a working potential of -0.35V vs. Ag/AgCl (sat.KCl), reaching the steady-state current within 40s after each addition of phenol solution with a range of 0-135μM and a limit of detection and quantification which are 0.019μM and 0.0633μM, respectively. The bioelectrode was used to determine the content in polyphenol in a local virgin olive oil.<br /> (Copyright © 2016 Elsevier Ltd. All rights reserved.)