Design and Development of Microfluidic Based Dielectric Sensors for Biomedical Applications

A microfluidic device capable of sensing even fraction of pico Farad capacitive change is proposed. Purpose of the developed device is fluid concentration identification and characterization on the basis of the dielectric permittivity. A microchannel, realized on Silicon layer, below a sensing capacitor formed by electrodes sputter printed on a glass substrate. Fluids inside the microchannel affects the capacitance that is measured by a standard electronic interface system. Experimental results obtained for different fluids injected in the microchannel demonstrate the ability of the system to differentiate the fluids and estimate their dielectric permittivity both as pure samples and as mixtures at varying concentration of solute fractions. This makes the device a promising building block for fluid mixing monitoring in microfluidic systems.