Synthesis and characterization of PEDOT-PEGDA blends for bioelectronic applications: Surface properties and effects on cell morphology

One of the burning questions in bioelectronics concerns the discovery of new materials which might properly couple the conductive properties of historical metallic electrodes and the softness of hydrogels structures, widely employed for engineered cell culture. This demand leads to the massive increase in the use of conductive polymers (CPs), such as Poly(3, 4-ethylenedioxythiophenes) (PEDOT:PSS) mixed with other polymers in order to reach the best compromise among conductivity, surface morphology and biocompatibility. In this work, we tested multiple blends of (PEDOT:PSS) with different percentages of poly(ethylene glycol) diacrylate (PEGDA), a photoactive crosslinker which is highly employed for fabricating biomimetic interfaces. We carried out an accurate electrical and topographical characterization, also comparing spin and spray deposition techniques. The resulting blends were tested as cell culture substrates for primary fibroblasts cells. The biocompatibility and morphological analysis revealed that these materials can be suitable for this cell line. The best results in terms of conductivity, morphology and biocompatibility was accomplished in the case of the mixture PEDOT:PSS 8% PEGDA, which provides an essential starting point for future development of 3D organic electrodes and bioelectronics interfaces to be coupled with biological systems.