Rothwell, Sharon A. and Kinsella, Michael E. and Zaina, Zainiharyati M. and Serra, Pier A. and Rocchitta, Gaia and Lowry, John P. and O'Neill, Robert D. (2009) Contributions by a Novel Edge Effect to the Permselectivity of an Electrosynthesized Polymer for Microbiosensor Applications. Analytical Chemistry, 81 (10). pp. 3911-3918. ISSN 0003-2700

Preview

Download (275kB) | Preview

Abstract

Pt electrodes of different sizes (2 × 10−5−2 × 10−2 cm2) and geometries (disks and cylinders) were coated with the ultrathin non-conducting form of poly(o-phenylenediamine), PPD, using amperometric electrosynthesis. Analysis of the ascorbic acid (AA) and H2O2 apparent permeabilities for these Pt/PPD sensors revealed that the PPD deposited near the electrode insulation (Teflon or glass edge) was not as effective as the bulk surface PPD for blocking AA access to the Pt substrate. This discovery impacts on the design of implantable biosensors where electrodeposited polymers, such as PPD, are commonly used as the permselective barrier to block electroactive interference by reducing agents present in the target medium. The undesirable “edge effect” was particularly marked for small disk electrodes which have a high edge density (ratio of PPD-insulation edge length to electrode area), but was essentially absent for cylinder electrodes with a length of >0.2 mm. Sample biosensors, with a configuration based on these findings (25 μm diameter Pt fiber cylinders) and designed for brain neurotransmitter l-glutamate, behaved well in vitro in terms of Glu sensitivity and AA blocking.

Item Type:	Article
Keywords:	Novel Edge Effect; Permselectivity; Electrosynthesized Polymer; Microbiosensor Applications;
Academic Unit:	Faculty of Science and Engineering > Chemistry
Item ID:	8032
Identification Number:	https://doi.org/10.1021/ac900162c
Depositing User:	John Lowry
Date Deposited:	20 Mar 2017 17:27
Journal or Publication Title:	Analytical Chemistry
Publisher:	American Chemical Society
Refereed:	Yes
Funders:	Irish Research Council for Science Engineering and Technology (IRCSET), Science Foundation Ireland (SFI)
URI:	http://pubs.acs.org
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

Repository Staff Only(login required)

Item control page

Downloads

Origin of downloads