Optimization of bipolar and tetrapolar impedance biosensors

Impedance detection plays a crucial role in the development of Lab-on-a-Chip (LOAC) technologies. Various types of impedance biosensors have been developed over the years, with the main focus being centered on interdigital sensors. Optimization of impedance sensors has only recently attracted interest. In this paper we present a conformal mapping approach to the optimization of bipolar and tetrapolar impedance sensors. This technique enables an analytic equation for the sensitivity of the sensors to impedance changes to be obtained. Optimization of these sensors using this analytic equation was performed and a number of optimized sensor designs are presented in this paper.