In addition to an electrically conductive ECM-like fibre structure, a successful cardiac patch needs to exhibit biomechanical properties close to the human myocardium. In addition, detailed analysis of electrical bulk conductivities of PANi containing cast gelatin films highlighted a profound effect of the intrinsically conductive polymer, as average conductivity values of 1.5 mS/cm were observed, three times higher values than those of pure gelatin films. Thermoanalytical measurements (TGA, DSC) proved a protein-stabilising effect of gelatin by polyaniline and a generally improved thermal stability of the fibres. Chemical characterisation, including Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and UV-VIS spectroscopy measurements confirmed a successful introduction of the protonated conductive emeraldine salt form of PANi into the fibrous structure. It was found that by incorporating the electrically conductive polymer, both in powder form and by in situ polymerisation, the average fibre diameter of electrospun mats decreased by a factor of two, indicating an enhanced conductivity of the spinning solutions. Results were then compared with electrospun fibre mats, where polyaniline in emeraldine base powder form was successfully incorporated in gelatin before electrospinning. To introduce and electrospin polyaniline containing gelatin, a novel in situ polymerisation technique for PANi directly in the gelatin spinning solution was conceived and analysed. Since polyaniline occurs in diverse variations with differences in morphology and electrical conductivity, two main polymerisation routes were discussed and compared.
In the present work, several biomaterial-based approaches have been developed using electrospinning of gelatin-polyaniline (PANi) combinations as well as highly porous poly (glycerol sebacate) (PGS) substrates for the fabrication of 3D structured support patches for cardiac tissue engineering (CTE) applications. Due to the limited regenerative capacity of the myocardium and the shortage of donor organs, myocardial tissue engineering offers alternative strategies to produce functional myocardial tissue. One of the most common causes of death worldwide are cardiovascular diseases such as myocardial infarction.