Development of an impedance spectroscopy device for on-line cell growth monitoring

The impedance and dielectric properties of biological samples are often used to estimate the number of cells growing in a culture, and monitor the cell growth in real time. For these type of studies, high-cost and complex commercial equipment is often required. The design and implementation of a standalone device for impedance spectroscopy of cell samples is presented, featuring low cost, portability and easy reconfigurability of frequency and voltage. The device can generate sinusoidal, square and triangular signals with frequencies up to 125 kHz, at voltages in the range from 0 V to 100 mV. Cell growth experiments were carried out with yeast cultures, and the results are compared with a commercial Agilent 4284A LCR meter. The error percentages for magnitude and phase measurements are <5%.