EMAIL THIS PAGE TO A FRIEND

Biosensors & bioelectronics

The effect of the oxidation state of a terthiophene-conducting polymer and of the presence of a redox probe on its gene-sensing properties.


PMID 18790630

Abstract

The gene-sensing properties of sensor films made of a terthiophene-conducting polymer, poly(3-((2':2'', 5'':2'''-terthiophene)-3''-yl)acrylic acid) (PTAA), were evaluated using electrochemical impedance spectroscopy for films in their reduced and oxidised states with and without the Fe(CN)(6)(3-/4-) redox probe (RP) in dilute tris-EDTA buffer. Porous films of PTAA were prepared and attached to an oligonucleotide sequence specific to the Salmonella virulence gene InvA. These films could be described with a dual transmission line model in which the polymer conductivity was increased as a consequence of surface binding of complementary DNA. The effect is analogous to that reported for silicon nanowires and field-effect transistors in dilute electrolyte modified by charge exchange across the polymer-electrolyte interface. As a result, gene sensing could be conveniently observed as a change in the impedance phase angle at a fixed frequency.

Related Materials

Product #

Image

Description

Molecular Formula

Add to Cart

311073
2,2′:5′,2′′-Terthiophene, 99%
C12H8S3