Optical biopsy is the most commonly used method in cell growth studies. This study designs a Petri dish with a 32-electrode array for electronic biopsy. A simplified electrical model of a cell culture is proposed. Electrical impedance spectroscopy has been widely applied to characterize the electrical properties of cells during culture. To determine the electrical properties of PC12 cells for electronic biopsy, the Cole-Cole plot method is used for feature extraction. The analysis uses an equivalent three-element circuit model with a constant-phase element. A distribution curve is also used to determine how parameters affect the impedance loci in the three-element model. A PC12 cell line continuously cultured for 30 hrs without change of medium is used to illustrate the feasibility of the proposed electronic biopsy. The results show that the maximum phase decreases and the other parameter curves increase when cell necrosis occurs. The slope of Cole-parameters and diameter of Cole-Cole plots are useful for cell growth and cell property characterization.