Permselectivity and ion-exchange properties of Eastman-AQ polymers on glassy carbon electrodes

Abstract

Eastman-AQ55D is a new poly(ester sulfonic acid) cation exchanger available in a commercial dissolved form. Films of this polymer were coated onto glassy carbon surfaces, and the resulting electrodes exhibit attractive permselectivity, ion-exchange, and antifouling properties. Substantial improvement in the selectivity is observed as a result of excluding anionic species from the surface. The charge-selective behavior is demonstrated in the presence of a variety of compounds of neurological significance. A rapid response to dynamic changes in the concentration of cationic and neutral species is observed. The polymer strongly binds multiply charged counterions. Cyclic voltammetry is used to determine the quantity of incorporated ions as a function of time, concentration, and other variables. The oxidation of hydrogen peroxide is catalyzed when Ru(bpy)3(2+) is incorporated in the coating. The film can also protect the substrate electrode from foulants present in the contacting solution. These features, as well as the low cost, simple coating procedure, strong adherence to surfaces, and versatility, make the Eastman-AQ55D polymer well-suited for a variety of electro-analytical applications.

Surface Improvement of Glassy Carbon Electrode Anodized in Triethylene Glycol and Its Application to Electrochemical HPLC Analysis of Protein-Containing Samples

“…Polymeric coating has proved to be one feasible technique for this purpose. [1][2][3][4][5][6][7][8] However, polymer-coated electrodes appear to have a limited number of applications, 2,7 with the exception of stripping analysis of trace metals. [3][4][5][6]8 This may be due to slow mass transport of organic analytes in the membrane.…”

Electrochemical Coating with Poly(phenylene oxide) Films Bearing Oligoether Groups as a Tool for Elimination of Protein Adsorption to Electrode Surfaces

“…Electrode 5 is likely to resist protein adsorption with efficiency comparable to or slightly less than GC electrodes coated with membranes such as a basehydrolyzed cellulosic film 2 or poly(ester sulfonic acid) 7 , 638 ANALYTICAL SCIENCES JULY 1999, VOL. 15 and much more effectively than a GC electrode modified with p-carboxymethylphenyl group.…”

“…To circumvent this problem, there have been many efforts to develop modification methods that would increase surface hydrophilicity and thus decrease protein adsorption. Coating with membranes such as cellulose acetate 1 , a base-hydrolyzed cellulosic film 2,3 , Nafion 4,5 , or poly(ester sulfonic acid) [6][7][8] has proven to be a feasible technique for this purpose. However, membranecoated electrodes seem to have found only a few applications 2,7 , except in stripping analysis of trace metals [3][4][5][6]8 , probably due to the slow mass transport of organic analytes in thick and well-packed polymeric membranes.…”

Immobilization of Glucose Oxidase on a Poly(dimethylsiloxane) Layer by Using Poly(l-lysine) as a Polymer Backbone

“…A layer for discriminating oxygen or hydrogen peroxide from the electrochemical interferences is strongly desired to develop a sensing system. [1][2][3][4][5][6] Recently, we have reported that the porous and hydrophobic properties of a poly(dimethylsiloxane) (PDMS) layer are suitable for restricting hydrophilic interferences and hydrogen peroxide, while allowing permeating gases, such as oxygen 7 and nitric oxide 8,9 selectively. The permeability of several electroactive species through a PDMS layer on the electrode has been investigated in detail.…”