3D Bioelectronic Platforms for Monitoring and Guiding Stem Cell-to-Neuron Development

Organic electronic materials, notably conducting polymers, enable functional 3D bioelectronic interfaces and bridge the dimensionality mismatch between 2D/static electronics and 3D/dynamic biology. Here, we describe the development of biomimetic 3D platforms for in vitro stem cell cultures by combining organic electronic materials, extracellular matrix materials, and microfabrication techniques. First, we demonstrate the development of electroactive, porous scaffolds based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and their integration into an electrode configuration. These 3D bioelectronic devices are used as platforms for 3D human adipose-derived stem cell (hADSC) growth and their differentiation into neuron-like cells. We employed electrochemical impedance spectroscopy to non-invasively monitor these biological processes. Next, we present the development of 3D multifunctional porous scaffolds that exhibit both electrical conductivity and photosensitivity. Water-based solution mixtures of PEDOT:PSS and the semiconducting polymer P3CPT are transformed into 3D scaffolds via freeze-drying. Evidence shows that light can be converted into a bioelectric cue, assisting the differentiation of hADSCs into neurons. Finally, we describe the development of electrically conducting hydrogels and their use in creating 3D neural networks from human induced pluripotent stem cells (iPSCs). We combine PEDOT:PSS with classic hydrogel materials as well as extracellular matrix materials to synthesize biocompatible, conductive, and transparent hydrogels under physiological conditions.<br/> <br/><u>References</u>:<br/>[1] 3D organic bioelectronics for electrical monitoring of human adult stem cells, A. Savva,* J. Saez, A. Withers, V. Stoeger, C. Barberio, S. Elias-Kirma, Z. Lu, C.-M. Moysidou, K. Kallitsis, C. Pitsalidis, R.M. Owens, Materials Horizons, 2023, 10, 3589-3600.