Fabrication of conductive gelatin methacrylate-polyaniline hydrogels

Abstract

Hydrogels with inherently conductive properties have been recently developed for tissue engineering applications, to serve as bioactive scaffolds to electrically stimulate cells and modulate their function. In this work, we have used interfacial polymerization of aniline monomers within gelatin methacrylate (GelMA) to develop a conductive hybrid composite. We demonstrate that as compared to pure GelMA, GelMA-polyaniline (GelMA-Pani) composite has similar swelling properties and compressive modulus, comparable cell adhesion and spreading responses, and superior electrical properties. Additionally, we demonstrate that GelMA-Pani composite can be printed in complex user-defined geometries using digital projection stereolithography, and will be useful in developing next-generation bioelectrical interfaces.

Statement of significance: We report the fabrication of a conductive hydrogel using naturally-derived gelatin methyacrylate (GelMA) and inherently conductive polyaniline (Pani). This work is significant, as GelMA-Pani composite has superior electrical properties as compared to pure Gelma, all the while maintaining biomimetic physical and biocompatible properties. Moreover, the ability to fabricate conductive-GelMA in complex user-defined micro-geometries, address the significant processing challenges associated with all inherently conductive polymers including Pani. The methodology described in this work can be extended to several conductive polymers and hydrogels, to develop new biocompatible electrically active interfaces.

Keywords: Conductive hydrogels; Fabrication methods; Gelatin methacrylate; Polyaniline; Processing; Scaffolds.