[9a-S421-1~12] 12.7 Biomedical Engineering and Biochips

▲ [9a-S421-1] DNA 3D structure detection by Electrochemical Impedance Spectroscopy (EIS)

〇Huanwen Han¹, Kazuyuki Nobusawa¹, Fumie Takei², Ichiro Yamashita¹ (1.Grad. Sch. of Eng., Osaka Univ., 2.NDMC)

Keywords:Electrochemical Impedance Spectroscopy, DNA structure

Easy, fast and trusty DNA sequencing and detection has been a central issue in clinical research, like pathogen's identification, drug resistance sensitivity. Many sensing principles have been studied, such as Field Effect Transistor (FET), Surface Plasmon Resonance (SPR), Quartz crystal Micro valance (QCM) and Electrochemical impedance spectroscopy (EIS). Among them, EIS has high sensitivity under a wide variety of solution conditions and is non-destructive and label-free measurement method ^[1]. EIS detects impedance of the modified electrode ^[2]. The interface is represented as an equivalent circuit, Randles equivalent circuit with Warburg. Randles circuit is a parallel capacitance and resistance, which represent charge bilayer capacitance and charges transfer resistance (Rct) respectively. Rct changes ^[3] depending on the molecular absorption and accumulation on the electrode surface. In this study, we compare the performance of two DNA probes with EIS.