Preparation and characterization of TIO2/SPI composite film

Nanocrystalline titanium dioxide (TiO2) particles coated with soy protein isolate (SPI) were fabricated in aqueous solution at near room temperature. The X-ray diffraction, UV scanning spectrum, photoluminescence and FT-IR measurements were applied to characterize the nanoscaled composite structure of SPI/TiO2. Laser scattering particle analyzer and zeta potential were used to determine the average particle size and stability of the system in basic solutions by adding various amounts of titanium dioxide. When exposed to two hour irradiation of UV light at 365 nm, the bactericidal activity of SPI films containing TiO2 nanoparticles (2.00 g/150 mL) against Escherichia coli and Staphylococcus aureus can reach 71.01% and 88.49%, respectively.

► TIO2/SPI composite film was fabricated by Nano-TiO2 solution and SPI.
► X-ray, UV–vis, FT-IR and XRD were applied to characterize the structure.
► TIO2/SPI composite film showed the bactericidal activity.
► We report here its preparation and characterization for the first time.