Dielectric-based biosensors.

A basic background is given of the concepts and measurements of dielectric phenomena, and two examples of dielectric-based biosensors are described. The way in which the dielectric properties of immobilized urease can be used to monitor the hydrolysis of urea is first outlined, while the second example describes how the phenomenon of dielectrophoresis can be used to monitor the concentration and viability of suspensions of cells or micro-organisms.