Topographical and Electrical Stimulation of Neuronal Cells through Microwrinkled Conducting Polymer Biointerfaces

The development of smart biointerfaces combining multiple functions is crucial for triggering a variety of cellular responses. In this work, wrinkled organic interfaces based on the conducting polymer poly(3,4-ethylene dioxythiophene) doped with poly(styrene sulfonate) are developed with the aim to simultaneously convey electrical and topographical stimuli to cultured cells. The surface wrinkling of thin films on heat-shrink polymer sheets allows for rapid patterning of self-assembled anisotropic topographies characterized by micro/sub-microscale aligned wrinkles. The developed interfaces prove to support the growth and differentiation of neural cells (SH-SY5Y, human neuroblastoma) and are remarkably effective in promoting axonal guidance, by guiding and stimulating the neurite growth in differentiating cells. Electrical stimulation with biphasic pulses delivered through the conductive wrinkled interface is found to further promote the neurite growth, demonstrating the suitability of such interfaces as platforms for conveying multiple stimuli to cells and tissues.