Low nM Detection Limits at Porous 1–3 nm Thick Membrane‐Coated Nanostructured Microdisk Electrodes

Abstract

Low (15 nM) limits of detection (LOD) of dopamine were obtained at porous 1–3 nm‐thick overoxidized polypyrrole (OPPY) membrane‐coated microdisk carbon fiber electrodes of small size (r=3.5 µm). The excellent mass transport through the porous OPPY membrane (efficiency as good as solution transport) contributes to the low LOD, together with dopamine preconcentration in the membrane. Structural characterization of the membrane coated electrodes confirms the contribution of membrane nanostructure to the high sensitivity and the low LOD.

Morphological changes in electrochemically deposited poly(3,4-ethylenedioxythiophene) films during overoxidation

“…For instance, many studies have demonstrated that overoxidized polypyrrole films exhibit molecular-sieve properties and such films have been used to fabricate glucose, alcohol, hydrazine, and dopamine sensors [25][26][27][28][29][30][31][32]. A demonstration of an organic electronic ion pump containing parts made of overoxidized PEDOT:PSS (poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate)) was provided in refs.…”

The Electrochemical Degradation of Poly(3,4-ethylenedioxythiophene) Films Electrodeposited from Aqueous Solutions

“…For instance, many studies have demonstrated that overoxidized polypyrrole films exhibit molecular-sieve properties, and such films have been used to fabricate glucose, alcohol, hydrazine, and dopamine sensors [29,[32][33][34][35][36]. (Over)oxidized PEDOT films were successfully used for sensing perchlorate [37].…”

“…According to [38] overoxidized poly (3,4-ethylenedioxythiophene) film-modified screen-printed carbon electrodes exhibited superior sensitivity and selectivity to dopamine. However, the basis for the observed selectivity of overoxidized polymer films is still not entirely clear [24,36,39].…”

Structural changes during the overoxidation of electrochemically deposited poly(3,4-ethylenedioxythiophene) films

“…For instance, many studies have demonstrated that overoxidized polypyrrole films exhibit molecular-sieve properties, and such films have been used to fabricate glucose, alcohol, hydrazine, and dopamine sensors [25][26][27][28][29][30][31][32]. (Over)oxidized PEDOT films were successfully used for sensing perchlorate [33].…”

“…According to [34] overoxidized poly(3,4-ethylenedioxythiophene) film-modified screen-printed carbon electrodes exhibited superior sensitivity and selectivity to dopamine. However, the basis for the observed selectivity of overoxidized polymer films is not entirely clear [32,35,36].…”