Given that most bioelectronic device applications operate in ionic media, we sought to understand how the electronic properties were affected by the adherence of cells. Cells were seeded onto UV-Ozone treated pDPP3T films and impedance was monitored as a function of time. Electrical impedance spectroscopy (EIS) is a well utilised method for cell growth monitoring as impedance can be measured across a range of frequencies allowing for the electrical resistance and capacitance of cells to be extracted . The pDPP3T treated films were cast onto ITO coated glass and used as the working electrode in a three-electrode electrochemical cell with platinum counter and Ag/AgCl reference electrodes. From our previous results, we found that t = 30 s exposure was suitable for promotion of cell growth while maintaining the electrical properties of the pDPP3T film. Therefore, the films were UV-Ozone treated using this optimised time before seeding with SCL4.1/F7 Schwann cells. As a control, 30 s UV-Ozone treated pDPP3T films were tested in cell culture media with no cells. EIS measurements were taken immediately before seeding (0 h), and at 6, 18, 24, 48, and 120 hours. The resulting impedance and phase plots for the films with and without Schwann cells are shown in Figure and Figure respectively. A clear reduction in low frequency (<100 Hz) impedance over time was observed in the pDPP3T films without cells (see Supplementary Figure for 100 Hz and 1 kHz measurements).