3D silk fibroin scaffold incorporating titanium dioxide (TiO2) nanoparticle (NPs) for tissue engineering

The present study deals with fabrication of scaffolds composing of silk fibroin and TiO2 NPs fabricated using a salt-leaching process. At first instance, the TiO2 NPs were prepared by using sol-gel synthesis, affording to have average diameter of 77±21μm. Furthermore, the aqueous solutions of silk fibroin were mixed with 0.2%, 2.0% and 4.0% of TiO2 NPs and salt-leaching process was introduced which resulted in creation of porous scaffolds modified with TiO2 NPs. The presence of TiO2 NPs in scaffolds was confirmed by VP-FE-SEM-EDS, TGA and XRD. The presence of TiO2 NPs influenced in decrease in pore size and swelling behavior of composite scaffolds. The resultant mechanical property of scaffolds was improved upon the introduction of TiO2 NPs. Moreover, cell cytotoxicity results for 1, 3 and 7 days; revealed no toxic behavior to osteoblasts. However, a mild toxicity to NIH 3T3 fibroblasts was observed with the scaffolds containing 4.0% TiO2 NPs. The cell fixation results from 1 and 7 days of incubation indicated the attachment, spreading and subsequent proliferation of fibroblasts. However, these findings were independent to the amount of TiO2 NPs in scaffolds.