Conducting-Polymer-Based Chemical Sensors: Transduction Mechanisms

Abstract

Conducting organic polymers show great promise as sensory materials. The transport of charge in these systems imparts the ability to attain high sensitivity to analytes of interest. This contribution reviews a number of different mechanisms by which analytes can interact with organic conducting polymers to create changes in their resistivity. New sensor systems based upon triaryl-methyl carbocations are also reported for the first time. The design of specific molecular recognition can impart selectivity in this process and in addition the nature of the conducting polymer can also lead to selectivity for different analytes.

Analysis of Conjugated Polymers Conductivity by in situ Electrochemical‐Conductance Method

“…Since conducting polymers conductivity is a bulk transport property, small perturbations on the mobility of the counterions or the charge carrier's (electrons or holes) results in higher conductivity changes compared to possible variations in potential or current . This phenomena may be amplified if the analyte recognition site is located inside of the backbone structure of the monomer .…”

“…Since conducting polymers conductivity is a bulk transport property, small perturbations on the mobility of the counterions or the charge carrier's (electrons or holes) results in higher conductivity changes compared to possible variations in potential or current . This phenomena may be amplified if the analyte recognition site is located inside of the backbone structure of the monomer . Swager's group has extensively studied these types of interactions and, by means of the in‐situ electrochemical‐conductivity technique, has developed different monomers types for their possible application as conductometric sensory devices .…”

Development of radio-frequency identification sensors based on organic electronic sensing materials for selective detection of toxic vapors

“…16,17 In addition, the inherent electrical transport property and energy migration of intrinsically conducting polymers can also facilitate the enhancement of material 18 and readout 16 sensitivity. Intrinsically conducting polymers promise to dramatically expand the range of detected analytes and improve their detection limits.…”

Urea Biosensor Based on Conducting Polymer Transducers

“…A potentiometric and amperometric signals can be read through a single electrode [20]. Conductometric sensor devices, on the other hand, are most easily monitored by passing charge between two electrodes.…”