Naturally derived silk fibroin/gelatin composites as novel sacrificial template for synthesis of silica nanotubes with controllable size and their in vitro biocompatibility

Silica nanotubes with controllable size were synthesized as the electrospun silk fibroin/gelatin composite nanofibers as novel sacrificial template were firstly coated with silica in the Stöber-type sol-gel precursor and then burned out at 600 °C. The aqueous stability of composite nanofibers was much better than that of gelatin nanofibers due to the presence of silk fibroin. FT-IR spectrum showed that silica nanotubes had the strong adsorption band at 1115 cm −1 for Si–O–Si groups. TEM observation showed that the diameter of silica nanotubes could be controlled from 225 ± 11 nm to 470 ± 9 nm by tuning the silk fibroin/gelatin weight ratio from 1.25 to 2. After incubation with the osteoblast MG63 cells, silica nanotubes (0–200 μg/mL) had no significant cytotoxicity and presented excellent biocompatibility.