Tailor-made conductive PANI-coated nanofibers for tissue engineering applications

Due to the challenges related to the cytotoxicity of polyaniline (PANI), tissue engineering applications of PANIcoated nanofibers are limited. For this reason, PANI-based nanofibers are usually made through the blending of PANI and biocompatible polymers to reduce the cytotoxicity of the final scaffold. In the present study, PANIcoated nanofibers with no cytotoxic effects were prepared. Two types of PANI-coated nanofibers with different dopants including hydrochloric acid (HCl) and taurine (Tau) were fabricated, characterized, and compared to introduce a conductive scaffold with no cytotoxicity. In fact, Tau as a bioactive dopant was used to enhance the biocompatibility of PANI-coated nanofibers. To this end, plasma-treated poly(ethersulfone) (PES) electrospun nanofibers were used as the template. Then, the PANI-coated nanofibers were fabricated via in situ chemical oxidative polymerization of PANI-HCl and PANI-Tau. The PANI-coated nanofibers were assessed by microscopy, infrared spectroscopy, porosity analysis, conductivity analysis, contact angle measurement, and indirect MTT assay to ascertain the effects of dopants on the properties of the nanofibers. Severe cytotoxicity was observed in the extraction of the PES/PANI-HCl nanofibers, while the extraction of PES/PANI-Tau nanofibers enhanced cell viability. On the other hand, between PANI-HCl and PANI-Tau, the first compound had higher conductivity while the second one had higher conductivity stability in the cell culture medium. With respect to the biocompatibility and physicochemical properties of the above-mentioned nanofibers, Tau-doped-PANIcoated nanofibers could be considered as a novel biocompatible conductive scaffold for tissue engineering applications.