Synthesis and characterization of electrically conducting polymers for regenerative engineering applications: sulfonated ionic membranes

Conductive polymers have found extensive application in fuel cells, sensors and more recently as scaffolds for tissue and organ regeneration. Scaffolds that can transmit electrical impulses have been shown to be beneficial in regeneration of tissues like muscle and nerve that are electroactive in nature. Most cellular events and cell functions are regulated by ion movement, and their imbalance is the cause of several diseases. We report synthesis and characterization of sulfonated polymers of poly(methyl vinyl ether‐alt‐maleic anhydride) (PMVEMA), poly(ether ether ketone) (PEEK), poly(ether sulfone) (PES) and poly(phenylene oxide) (PPO) and evaluate their potential for tissue regeneration. The ionic conductive property stems from the presence of sulfonic groups on the polymer backbone. The structure of the polymer was confirmed using Fourier Transform Infrared Spectroscopy and membrane hydrophicity was determined by water contact angle measurement. The electrical conductivity of these sulfonated membranes was found to be 53.55, 35.39 and 29.51 mS/cm for SPPO, SPEEK and SPMVEMA, respectively. The conductivity was directly proportional to the sulfonic acid content on the polymer backbone. The ionic membranes namely SPPO, SPEEK and SPMVEMA demonstrated superior cell adhesion properties (~7–10 fold higher) than cells seeded onto tissue culture polystyrene. The sulfonated membranes exhibited static water contact angle in the range of 70–76°. The membranes supported the proliferation of human skin fibroblasts over 14 days in culture as evidenced by confocal and electron microscopy imaging. The ionic materials reported in this study may serve as scaffolds for a variety of tissue healing and drug delivery applications. Copyright © 2014 John Wiley & Sons, Ltd.