Abstract
Impedance detection based on a non-faradaic process is suitable for making real-time label-free biosensors by measuring the capacitance change at the electrode-solution interface. A few capacitive DNA sensors have been developed in recent years with detection limits ranging from sub-attomolar to micromolar. This chapter provides a summary of the sensing principles, detection methods, and related works in this field. To realize miniaturized, highly sensitive, and cost-effective capacitive DNA sensor arrays for point-of-care applications, it is advantageous to integrate sensing electrodes and capacitive readout in a single chip by using integrated-circuit technologies.