Controlling Mammalian Cell Detachment via The PEDOT:PSS Redox Reaction

Cell-based assays are some of the most common experiments for biomedical research across a wide range of fields. Many researchers perform cell culture tasks daily at large scale. Therefore, developing a fast, simple, enzyme-free, non-damaging and effective technology for on-demand cell detachment could improve the ability to culture delicate cell types, as well as enable new modalities for automating cell culture workflows. Here, we demonstrate the use of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) surfaces as a cell culture surface with excellent biocompatibility, and the ability to significantly decrease cell adhesion on demand. The application of AC voltage to PEDOT:PSS cycles a redox reaction which results in ion flux at the cell-surface interface, and disrupts cell adhesion, allowing cells to be more easily detached from the surface. The application of 5V resulted in cell cells becoming more rounded within minutes. At the same shear force (1.5nN), cell detachment can be increased from 1% to 95% by tailoring the frequency of the voltage applied. For this system, the optimal frequency was found to be 0.05 Hz. However, at higher frequencies (a frequency of 0.1 Hz and above), the redox reaction does not have time to fully complete, and the cell adhesion is not significantly impacted. Cell viability was not significantly impacted by the use of PEDOT:PSS as a cell culture material or by the application of voltage to the surface, with viability &gt;90%. In all, this suggests that PEDOT:PSS could be used as a cell culture material that allows for on demand cell detachment <i>via</i> a simple voltage application.