Effect of copper nanoparticles on physico-chemical properties of chitosan and gelatin-based scaffold developed for skin tissue engineering application

Development of new and effective scaffold continues to be an area of intense research in skin tissue engineering. The objective of this study was to study the effect of copper nanoparticles over physico-chemical properties of the chitosan and gelatin composite scaffolds for skin tissue engineering. The copper-doped scaffolds were prepared using freeze-drying method. Chitosan and gelatin were taken in varied composition with 0.01%, 0.02%, and 0.03% Cu nanoparticles. The physico-chemical properties of the copper nanoparticles and the scaffolds were analyzed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy. Porosity of the scaffolds was measured by liquid displacement method and hemocompatibility was tested using goat blood. SEM micrographs of the scaffolds displayed the interconnected pores which ranged between 25 and 40 µm. This average pore size was later enhanced to 95 µm after the addition of copper nanoparticles. Cell viability assay was performed to ensure the growth and proliferation of the skin cells over the scaffolds. FTIR, EDS, and XRD analysis of scaffolds confirmed the presence of copper in the chitosan-based scaffolds. Porosity measurement showed the interconnectivity between pores which ranged between 65 and 88% as required for skin tissue engineering application. The degradation study of the scaffolds was done which depicted that, after the addition of copper nanoparticles with 0.03%, degradation rate was decreased. SEM and cytocompatibility assay on all scaffolds showed the cell adhesion and proliferation on the scaffolds which was not affected after addition of copper nanoparticles. Oxidative stress evaluation was done to study the effect of copper nanoparticles on the cells which showed that there was no such production of ROS in the scaffolds. Hence, scaffolds prepared after doping of copper nanoparticles show suitable physico-chemical and biological properties for skin tissue engineering application.