An antifouling electrode based on electrode–organic layer–nanoparticle constructs: Electrodeposited organic layers versus self-assembled monolayers

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 2016-10, Vol.779, p.229-235
• Main Authors: Taufik, Safura, Barfidokht, Abbas, Alam, Muhammad Tanzirul, Jiang, Cheng, Parker, Stephen G., Gooding, J. Justin
• Format: Article
• Language: English
• Subjects: Antifouling; Aromatic compounds; Aryl diazonium salts; Biosensors; Chemical reduction; Electrochemistry; Electrodes; Ethylene; Ethylene oxide; Gold; Human behavior; Monolayers; Nanoparticles; Protein adsorption; Proteins; Self-assembled monolayers; Self-assembly; Serum albumin
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2016.01.031

Electrodes modified with organic layers and nanoparticles are promising tools for analytical devices. A major challenge however is how to make electrodes that resist the nonspecific protein adsorption from biological media? Herein, we report gold electrode–organic layer-gold nanoparticle constructs as a platform for electrochemical biosensing. This study focuses on the fabrication of antifouling electrodes with the organic layers formed by two different approaches; self-assembled monolayer (SAM) procedure and electrochemical reduction of aryl diazonium salts, followed by the attachment of gold nanoparticle (AuNP) to allow the electrochemistry to proceed. The results show that the electrodes modified with ethylene oxide-based SAM enable a better antifouling behaviour with less adsorption of human serum albumin (HSA) as compared to the electrodes modified with ethylene oxide-based aryl diazonium-derived layer. Furthermore, findings suggest such distinction could be due to the surface packing and/or conformation of organic film on Au electrodes. •Fabrication of antifouling electrode as platform for electrochemical biosensing is demonstrated.•Two methods were employed for fabrication of antifouling electrode based on gold-organic layer-nanoparticle construct.•Self-assembled formation of organic layer has superior antifouling behaviour compared to those formed by electrodeposition.•The gold electrode-self assembled monolayer-nanoparticle construct is an ideal interface for biosensing in complex media.