Conductive nanostructured materials based on poly-(3,4-ethylenedioxythiophene) (PEDOT) and starch/κ-carrageenan for biomedical applications

Smart electroactive biomaterials are sought to allow the direct delivery of electrical, electrochemical and electromechanical signals to biological tissues. Specifically, poly-(3,4-ethylenedioxythiophene) (PEDOT) is a polymer of special interest attending to its biocompatibility, tuneable electrical conductivity and processing versatility. In this work, nanostructured PEDOT was synthesized using starch/kappa-carrageenan aerogels as templates. kappa-carrageenan biopolymer acted as doping agent of the conductive polymer to enhance the biocompatibility and the electrical response. The physicochemical, morphological, mechanical and electrical properties of the nanostructured PEDOT and templates were characterized. The incorporation of kappa-carrageenan to the nanostructured materials resulted in an increase in the compressive strength of ca. 40% and a decrease in the electrical impedance of one order-of-magnitude. The synergistic combination of the inherent electrical properties of the PEDOT, the advantageous features of kappa-carrageenan as doping agent and the porous morphology of the aerogel template resulted in electroactive PEDOT nanostructures with relevant properties for biomedical applications.