Injectable electroactive hydrogels based on Pluronic® F127 and tetraaniline copolymer

Nowadays, injectable electroactive hydrogels have received much attention in biomedical field. In this article, an electroactive copolymer was successfully synthesized by chemical coupling of tetraaniline (TA) onto the chain end of Pluronic F127. The structure of the resultant copolymer was characterized by Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), and H-1 NMR. Cyclic voltammetry (CV) measurements of the copolymer solution indicated good electroactivity. Moreover, the electroactive copolymer showed temperature-responsive sol-gel transitions in aqueous media. Gelation properties of the hydrogels were also studied by rheometer and the results showed that the introduction of TA segment could enhance the mechanical properties of hydrogel. Based on the analyses of C-13 NMR spectra and dynamic light scattering (DLS), the sol-gel transition mechanism was attributed to the dehydration of PEG chains in F127. The MTT assay revealed that the TA conjugated F127 copolymer showed excellent biocompatibility. And the copolymer could form gel in vivo at 15 min post injection. Therefore, this biocompatible copolymer acted as injectable electroactive hydrogels may have great potential in biomedical uses. (C) 2017 Elsevier Ltd. All rights reserved.