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Electroactive Polymer Nanoparticles Exhibiting Photothermal Properties
Published on: January 8, 2016
Constant Potential Amperometric Flow-Injection Analysis of Ions and Neutral Molecules Transduced by Electroactive
Marina D Zavolskova1, Vita N Nikitina1, Ekaterina D Maksimova1
1Chemistry Faculty of M. V. Lomonosov Moscow State University , 119991 , Moscow , Russia.
Abstract:
We first report on constant potential (dc) amperometric flow-injection analysis (FIA) transduced by electroactive (conductive) polymers. Amperometric response is caused by the polymer recharging in order to maintain the electrode potential at a constant level when (i) ions are crossing the film|solution interface and polarizing electrode|film interface or (ii) ions or neutral molecules are specifically interacting with the polymer recharging it. The response under constant solution flow is a current peak and in flow-injection mode is a couple of current peaks directed opposite of the first sharp, analytically valuable peak. In both constant flow and flow-injection regimes, the peak current is dependent on analyte concentrations; obviously, the FIA mode provides more advantageous analytical characteristics. Constant potential amperometric flow-injection analysis is shown for boronate- and sulfate-functionalized polyanilines as well as for Prussian Blue, a member of the inorganic polymer family. As a proof of concept, the successful dc amperometric detection of lactate in human sweat with boronate-functionalized polyaniline has been shown. The proposed approach would revolutionize the field of conductive/electroactive polymer-supported ion sensing with the introduction of reliable and robust amperometry as a valuable alternative to existing potentiometry.
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