Tuning Surface Charge and Morphology for the Efficient Detection of Dopamine under the Interferences of Uric Acid, Ascorbic Acid, and Protein Adsorption

• DOI: 10.1021/acsami.5b06526
• Publication Date: 2015-09-18T17:12:13Z
• Authors: Chien-Hsun Chen; Shyh-Chyang Luo
• Keywords: Protein Adsorption; Surface charge; Bovine serum albumin; Selective adsorption

In this research, we aimed to evaluate the impact of surface charges and morphologies electrodes on electrochemically detecting dopamine (DA) in presence protein adsorption, uric acid (UA), ascorbic (AA). Through electropolymerization functionalized 3,4-ethylenedioxythiophenes (EDOT) directly Au electrodes, successfully created PEDOT-coated with three different functional groups nanostructures. Negatively charged carboxylic attracted DA while reducing interferences UA AA due electrostatic effect. We used charge-free tetra(ethylene glycol) zwitterionic phosphocholine are interference adsorption sensing because they both can effectively prevent nonspecific proteins. These two avoid yet proved ineffective for sensing: electroneutral have minimal interactions DA. also proteins isoelectric points - bovine serum albumin, lysozyme, fibrinogen influence detection. found that an electrode coated acid-functionalized PEDOT, positively lysozyme promote detection sensitivity UA, all lowers contrast, nanostructures molecules. All our tested demonstrated good stability functionality buffers.