Titanium dioxide (TiO2) is a naturally occurring mineral that is mined from the earth, processed and refined, and added to a variety of foods, as well as other consumer products. White in color, it is used to enhance the color and sheen of certain foods and is also key for food safety applications. In its natural state it exists in different bulk crystalline forms, such as anatase and rutile, but during processing it is ground into a very fine powder.
Titanium dioxide (TiO2). Titanium dioxide is the most common white pigment used today. As a pigment, titanium dioxide is unique because it combines both high colouring and high opacifying capacity. This is mainly due to its high refractive index (2.7). Furthermore, titanium dioxide is an excellent UV absorber (it is used in sun protective creams). Some typical properties are: density 3.3-4.25 g/cm3; pH of water suspension 3.5-10.5; particle size 8–300 nm; oil absorption 10–45 g/100 g; specific surface area 7–160 m2/g. Most titanium dioxide is produced from the rutile (TiO2) or ilmenite (titanate of ferrous iron). Titanium dioxide can be obtained using different processes.
Fig. 6. AOPP measured on samples of MSSA with: A) 0.2 mg/mL P25TiO2NPs; B) 0.02 mg/mL P25TiO2NPs; C) 0.2 mg/mL VitaminB2@P25TiO2NPs; D) 0.02 mg/mL VitaminB2@P25TiO2NPs after 3 h of irradiation (red) and 6 h (blue). SD <1 (error bars too small to be seen) and p < 0.05 between C-D and A-B.