Designing and Implementing BIO-IMPEDANCE SPECTOROSCOPY DEVICE BY MEASURING IMPEDANCE IN A MOUSE TISSUE

Studies show that any complications including hemorrhage, lack of blood supply, lack of oxygen supply, and death of cells in a tissue, will have a clear effect on electrical properties of that tissue. Thus, by measuring impedance of a set of tissues, potential problems of the damaged tissue may be found. Since electrical impedance is closely related to the measuring frequency, obviously, every tissue exhibits its own specific impedance according to its electrical properties at each frequency. This research project investigates design and manufacture method of a device for measuring tissue impedance at different frequencies. To this end, design of a multi frequency sinusoidal current source is required. This current source is built using a single harmonic Generator sample (DDS AD9835) with working frequency (design-point frequency) between 1 Hz and 10 MHz and accuracy of 1 Hz, and microcontroller (PIC16F628) capability. For measurement and display of tissue impedance, ARM AT91SAMs256 microcontroller was used. Thus, with this hardware created, it shows that there are significant impedance changes between mouse tissues.