11:00 AM - 11:15 AM
▲ [8a-A502-8] Electrochemical Impedance Spectroscopy (EIS) for Bio-sensing
Keywords:Electrochemical impedance spectroscopy, Biosensor
A Lab on a chip (LoC) is integrated several laboratory processes in a device. Recently the LoC type bio-sensor is now attracting interests. The LoC type sensor carries out sample preparation, purification and sensing on a chip, which can reduce the time and sample amount for detection. The result can make it possible to decide rapid diagnostic/prescription. To realize such LoC-type biosensor, simple and high-sensitive biosensing method is necessary.
Electrochemical impedance spectroscopy (EIS) is now commonly used in battery researches and the interfaces among electrodes and electrolyte layer are characterized. This EIS measurement could be applied to interfaces between the electrode and aqueous solutions, i.e. bio-sensors [1]. From an electrical circuit point of view, the interface could be interpreted as a parallel-connected capacitance and resistance. The capacitance is from electric charge bilayer and the resistance is from the charge-transfer between electrode and mediator [2]. When the electrode is modified bio-receptor, the charge transfer resistance (Rct) increases in proportion to biomolecules absorption (Figure1). We are now proving this technique can be applicable to the DNA hybridization detection. In this presentation, we describe the EIS theory and experimental results.
Electrochemical impedance spectroscopy (EIS) is now commonly used in battery researches and the interfaces among electrodes and electrolyte layer are characterized. This EIS measurement could be applied to interfaces between the electrode and aqueous solutions, i.e. bio-sensors [1]. From an electrical circuit point of view, the interface could be interpreted as a parallel-connected capacitance and resistance. The capacitance is from electric charge bilayer and the resistance is from the charge-transfer between electrode and mediator [2]. When the electrode is modified bio-receptor, the charge transfer resistance (Rct) increases in proportion to biomolecules absorption (Figure1). We are now proving this technique can be applicable to the DNA hybridization detection. In this presentation, we describe the EIS theory and experimental results.