Novel Conducting, Biocompatible and Biodegradable Copolymer PEDOT-co-PLLA for Biomedical Applications

Electroactive biomaterials are a new generation of “smart” biomaterials based on conducting polymers. Poor molecular interaction with cells is the main challenge to face for the use of conducting polymers as biomaterials, even though that their biocompatibility can be highly improved by doping with specific anions but, despite this, electroactive polymers still present low or none biodegradability. The challenges for developing biomaterials for active scaffolds by electrical stimulation are: (1) the difficulty of working with conducting polymers which can only be obtained over electrodes by electrochemical synthesis; (2) to achieve surface chemistry which enables surface charge keeping biocompatibility for living cells culture and (3) poor compatibility between conducting and biodegradable polymers. Here we developed the synthesis of a novel electroactive, biodegradable and biocompatible copolymer (PEDOT-co-PDLLA) in different proportions of PEDOT:PDLLA (1:5; 1:25 and 1:50) which joins the properties of both homopolymers in a single biomaterial. Furthermore, we characterized/studied its surface properties as work function, charge/current distribution and surface chemistry by using Conductive Atomic Force Microscopy and Force Spectroscopy with an AFM-tip functionalized with Fibronectin as model protein. Additionally, the biocompatibility of PEDOT-co-PDLLA was investigated with Embryonic Stem Cells, showing an excellent growth and differentiation for Neural Cells with better results for PEDOT-co-PDLLA 1:50 in good agreement with AFM studies.