White crystalline powder. It is a mixture of zinc sulfide and barium sulfate. The more zinc sulfide it contains, the stronger the hiding power and the higher the quality. Density 4.136～4.34 g/cm3, insoluble in water. It easily decomposes when exposed to acid to produce hydrogen sulfide gas, but does not work when exposed to hydrogen sulfide and alkaline solutions. It turns into light gray after being exposed to ultraviolet rays in the sun for 6 to 7 hours, but it still returns to its original color when placed in a dark place. It is easy to oxidize in the air and will agglomerate and deteriorate when exposed to moisture.
Testing samples were made mixing 100 uL of TiO2NPs suspensions (0.2 mg/mL and 0.02 mg/mL) and vitamins@P25TiO2NPs (0.2 mg/mL and 0.02 mg/mL) with 100 μL ATCC 29,213 methicillin-sensitive Staphylococcus aureus (MSSA) (107 in PBS, pH 7). Controls were made replacing nanoparticles with the same volume of PBS. The concentrations of nanoparticle suspensions were chosen based on the FDA approved maximal and the minimal amount usually found in sunscreens, which are 20% and 2% (this is equivalent to 0.2 mg/mL and 0.02 mg/mL for nanoparticles suspensions). The cream concentration, on the other hand, was an intermediate value of 10%.
Titanium dioxide has similar uses in non-food products. It is used in sunscreen as effective protection against UVA/UVB rays from the sun, which creates a physical barrier between the sun’s rays and the skin. It’s also used to whiten paint, paper, plastic, ink, rubber, and cosmetics.
Lithopone, a white pigment composed of a mixture of barium sulfate and zinc sulfide, is commonly used in the leather industry as a coloring agent
. Leather suppliers around the world rely on lithopone to achieve the desired color and finish on their products.