Determination of the Aptamer Probe Density by Double Layer and Redox Capacitance of CNT-Based Electrochemical DNA-Aptasensors

• Published in: Proceedings - 2023 IEEE Regional Symposium on Micro and Nanoelectronics, RSM 2023
• Main Author: Mamun M.A.; Abdul Wahab Y.; Motalib Hossain M.A.; Hashem A.; Johan M.R.; Ezaila Alias N.; Hussin H.; Muhamad M.
• Format: Conference paper
• Language: English
• Published: Institute of Electrical and Electronics Engineers Inc. 2023
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85179843421&doi=10.1109%2fRSM59033.2023.10327172&partnerID=40&md5=2114e90b773c4a1697aff6508f438b7a

Electrochemical DNA-Aptasensors are gaining increasing popularity for the recognition of numerous analytes ranging from tiny molecules to entire microorganisms due to their multiple benefits over antibody-based biosensors. However, the reliable determination of aptamer probe density in DNA-Aptasensors is a potential barrier to ensuring their quality and performance. In this regard, an innovative, simple, and reliable electrochemical method has been introduced by exploring the redox capacitance (CR) using [Ru(NH3)6]3+/2+as a model redox species to determine the DNA-Aptamer probe density on a CNT (carbon nanotube) modified gc (glassy carbon) electrode surface. Moreover, the results were compared with the probe density calculated by the existing method using double layer capacitance (CD). Despite a lack of reproducibility caused by the non-specifically adsorbed aptamers on CNT, an excellent coincidence was found between the results obtained following those two methods. Therefore, the new method will accelerate the commercialization of electrochemical DNA-Aptasensors by confirming their quality through assessing the reliable DNA-Aptamer probe density. © 2023 IEEE.