Tu Yifeng, Zhai Suyan, Fang Chen, Zhao Qun and Yan Jilin
Soochow University, P R China
Posters & Accepted Abstracts: Insights Anal Electrochem
The variation of I27L gene associates with increasing risk of type 2 diabetes. It will be greatly significant to develop various methods to identify or monitor I27L genovariation. We report here a novel label-free electrochemiluminescent (ECL) DNA biosensor for simple and effective determination of I27L gene based on Au nanoparticles functionalized ITO electrode. The fabricated electrodes were characterized by scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The ECL technique was employed to monitor the hybridization of DNA by measuring the changes of its intensity. Here, the ECL signal was quenched since the electrostatic repulsion and space resistance of negatively charged sensor surface toward the probe (luminol anion) to block its access. The quantification of target strand was directly accomplished by calibrating the quenched ECL signals. Under optimal conditions, the decreased ECL intensity had a good linear relation upon the logarithm of target DNA concentration in the range of 1.0 �?�? 10â�?�?11 to 1.0 �?�? 10â�?�?7 M with a detection limit of 8.06 �?�? 10â�?�?12 M. In addition, the biosensor exhibited acceptable stability, excellent reproducibility and outstanding selectivity against one-base mismatched DNA. Whatâ�?�?s more is that the simple, low-cost, sensitive device could be easily miniaturized, which makes it an attractive candidate for integrating into portable platforms for point-of-care molecular diagnostics.
Tu Yifeng has completed PhD in 2002 from Nanjing University, China. He is currently a Professor and Supervisor of PhD students in Soochow University. He is the Director of the research group of “Analytical Chemistry for Life Sciences”. He has published more than 100 papers in reputed journals.