Self-actuating multilayer scaffold for skeletal muscle tissue engineering

Electroactive polymers (EAP) can alter and change their shape when subjected to an electric field, they have been investigated for a variety of purposes including smart drug delivery and artificial muscles. However, approaches to design electroactive hydrogel structures can be hindered by low polymeric conductivity, which then requires high electrical input to induce movement and results in low cellular viability. Our purpose in this study, was to reduce the input voltage required for movement by layering electroactive PEGDA:Acrylic acid (PEGDA:AA) with poly(ethylene glycol) diacrylate (PEGDA) modified with a conductive nanocomposite of colloidal poly(3,4 ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) and graphene oxide (GO). In this study PEDOT:PSS/GO was a flexible electrode that stimulated the PEGDA:AA. The multilayered hydrogel was evaluated for angular movement, electrical properties, and biocompatibility with C2C12 myoblast cells. The data showed that increasing the PEDOT:PSS/GO in the hydrogel decreased the conductivity, potentially due to the presence of GO. The addition of PEDOT:PSS/GO increased scaffold movement compared with PEGDA:AA alone when stimulated at 1 V. Fewer scaffolds displayed significantly more movement with increased voltage, but the 10% PEDOT:PSS/GO group experienced more movement at each tested voltage. C2C12 cells on the 10% PEDOT:PSS/GO were more metabolically active than cells on scaffolds with increased concentrations of PEDOT:PSS/GO. This work is an initial step in creating biocompatible scaffolds capable of actuation for tissue engineering.