The active role of biomaterials in the regeneration of tissues and their ability to modulate the behavior of stem cells in terms of their differentiation is highly advantageous. Here, polypyrrole, as a representantive of electro-conducting materials, is found to modulate the behavior of embryonic stem cells. Concretely, the aqueous extracts of polypyrrole induce neurogenesis within embryonic bodies formed from embryonic stem cells. This finding ledto an effort to determine the physiological cascade which is responsible for this effect. The polypyrrole modulates signaling pathways of Akt and ERK kinase through their phosphorylation. These effects are related to the presence of low-molecular-weight compounds present in aqueous polypyrrole extracts, determined by mass spectroscopy. The results show that consequences related to the modulation of stem cell differentiation must also be taken into account when polypyrrole is considered as a biomaterial.

Centre of Polymer Systems Tomas Bata University in Zlín 760 01 Zlín Czech Republic

Department of Experimental Biology Faculty of Science Masaryk University 625 00 Brno Czech Republic

Department of Surface Engineering Jožef Stefan Institute Jamova cesta 39 SI 1000 Ljubljana Slovenia

Faculty of Technology Tomas Bata University in Zlín 760 01 Zlín Czech Republic

Institute of Macromolecular Chemistry Academy of Sciences of the Czech Republic 162 06 Prague 6 Czech Republic

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Method for in situ polypyrrole coating, and the example of its use for functionalization of polyurethane anisotropic electrospun mats

New approach to prepare cytocompatible 3D scaffolds via the combination of sodium hyaluronate and colloidal particles of conductive polymers