Determination of the aptamer probe density by double layer and redox capacitance of CNT-based electrochemical DNA-aptasensors

• Main Authors: Mohammad Al Mamun, Mohammad Al Mamun, Abdul Wahab, Yasmin, Hossain, M. A. Motalib, Abu Hashem, Abu Hashem, Johan, Mohd. Rafie, Alias, Nurul Ezaila, Hussin, Hanim, Muhamad, Maizan
• Format: Conference or Workshop Item
• Published: 2023
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utm.my/108360/; http://dx.doi.org/10.1109/RSM59033.2023.10327172
• Institution: Universiti Teknologi Malaysia

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.