The Electrical Stimulation of Osteoblast Cell Lines Using Self-Doped Sulfonated Polyaniline-Based Interdigitated Electrodes

Electrically conducting polymers (CPs) were found to stimulate various cell types such as neurons, osteoblasts, fibroblasts in both in vitro and in vivo studies. Here we report a facile method of synthesis and fabrication of self-doped sulfonated polyaniline (SPAN)-based interdigitated electrodes (IDEs) for cell stimulation. In this method, layer-bylayer of SPAN copolymers were deposited by in situ polymerization on a micropattern printed polyethylene teraphthalate (PET) film. Bone marrow stromal cells (BMSCs) and pre-osteoblast cells (MC3T3-E1) were utilizing for the cell compatibility and proliferation studies. Increased degree of sulfonation was found to increase the SPAN conductivity, which improved the cell attachment and cell growth as well. The in vitro osteogenesis of the BMSCs or the MC3T3-E1 cells grown on the SPAN based IDEs under the electrical stimulation was investigated by utilizing an alkaline phosphatase (ALP) activity assay. The Von Kossa staining of the cells revealed significantly increased mineralization by both the cells comparing to their respective controls (without electrical stimulation). The high electrical conductivity and stability of the SPAN in a broad pH range of physiological culture medium in addition to the excellent cytocompatibility make the SPAN based IDEs as potential scaffold materials for in vitro cell culture and tissue engineering applications.