Preparation and modeling of electrospun polyhydroxybutyrate/polyaniline composite scaffold modified by plasma and printed by an inkjet method and its cellular study.

The reconstruction of the nerve tissue engineering scaffold is always of particular interest due to the inability to recover and repair neural tissues after being damaged by diseases or physical injuries. The primary purpose of this study was obtaining a model used to predict the diameter of the fibers of electrospun polyhydroxybutyrate (PHB) scaffolds. Accordingly, the range of operating parameters, namely the applied voltage, the distance between the nozzle to the collector, and solution concentration, was designed for the electrospinning process at three different levels, giving seventeen experiments. These data were modeled utilizing response surface methodology and artificial neural network method using Design Expert and Matlab software.The effect of process parameters on the diameter, as well as their interactions were investigated in detail, and the corresponding models were suggested. Both the RSM and ANN models showed an excellent agreement between the experimental and predicted response values. In the second phase of the study, PHB natural polymer was electrospun into scaffolds with high biocompatibility, resulting in a 224-360 nm diameter range .To further modify the scaffold in order to improve the compatibility of PHB, the fibrous surface of scaffolds was exposed to oxygenated plasma gas radiation under controlled conditions. Next, polyaniline (PANI) nanoparticles were then synthesized and printed on the surface of scaffolds as parallel lines. Then samples were exposed to the electric field. Fourier-transform infrared spectroscopy, water contact angle, optical and electron microscopy, tensile test, and cell viability analysis were performed to study properties of resulting scaffolds. The results indicated the fact that modification of the scaffolds by oxygen plasma and printing PANI nanoparticles in particular patterns had a favorable impact on cell adhesion and direction of cell growth, showing the potential of resulting scaffolds for nerve tissue engineering applications.