Non-faradaic electrochemical impedance spectroscopy analysis of C-MEMS derived bio-modified glassy carbon electrode

• Published in: Journal of micromechanics and microengineering Vol. 32; no. 8; pp. 84001 - 84007
• Main Authors: Patel, Rhea, Islam, Md Saiful, Mandal, Naresh, Pramanick, Bidhan
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.08.2022
• Subjects: bio modification; biosensor; C-MEMS; EIS; electrochemical sensing; glassy carbon
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/1361-6439/ac78bf

Abstract In this work, we have developed a carbon-microelectromechanical systems derived glassy carbon electrode (GCE) for non-faradaic electrochemical impedance spectroscopy (nf-EIS) measurement to detect electrode interfacial changes upon biomodification. This is carried out using a three-electrode system configuration. The fabricated electrode was electrochemically characterized in phosphate-buffered solution, and then changes in impedance were observed upon bio-modification of the electrode surface. The absence of any labelling molecule and no redox indicators makes the measurement system more straightforward and precise. The investigations were done using a standard deoxyribonucleic acid (DNA) immobilization on the GCE. The surface modification was done using a two-step assembly protocol linking the probe to the carbon electrode and blocking the unwanted sites using a spacer chemical-mercaptohexanol. The results obtained help us to understand the electrical signatures upon bio-modification of electrodes in the presence of a probe and its complementary 50 ng μ l −1 DNA target. nf-EIS relies on various microscopic interactions, which occur at the electrode–electrolyte interface system. We are currently working on extending this study to develop a precise, accurate and sensitive sensor to detect bio-molecular interactions occurring on the GCE to detect disease-causing microorganisms in contaminated water samples.