PC12 cells proliferation and morphological aspects: Inquiry into raffinose-grafted graphene oxide in silk fibroin-based scaffold

Highlights: • The idea of this research is to investigate the modified wonder biomaterial (i.e. graphene oxide) through chemical grafts of raffinose trisaccharide for bio-application. • In this literature, it has been considered how pristine graphene oxide (GO) and its grafted form with raffinose (RafGO) in the silk fibroin structure effect on proliferation, attachment, and some eminent neuron specific gene expressions. Peripheral nerves injuries (PNIs) still associated with both clinical and social problems. Accordingly, tissue engineers' and surgeons' attentions have been drawn for finding efficient solutions. Herein, scaffolds based on silk fibroin (SF)/raffinose-grafted-GO (S.RafGO) nanocomposite were fabricated. Subsequently, PC12 cells growth in term of number and morphology were investigated on neat SF polymer, SF/GO (S.GO), and S.RafGO scaffolds. Characterization via scanning electron microscopy (SEM) exhibited more fibrous structures with few lamellar nanosheets for S.GO; although, S.RafGO showed extended lamellar with lower fibrous structure. Due to the incorporation of GO and raffinose-GO nanosheets into SF structure, electrical conductivity increased ~30 and 40%, respectively. Water contact angle data revealed that S.RafGO is more wettable than SF and S.GO. Real-time PCR technique detected higher expressions of the β-tubulin, MAP2 genes on S.RafGO scaffolds in comparison with S.GO and the control group. Immunocytochemistry staining studies confirmed the overexpression of neural-specific proteins including nestin, β-tubulin of S.GO, and S.RafGO nanocomposites in comparison with pure SF scaffolds.