paint pigment factories

When used in food specifically, titanium dioxide is known as an additive called E171 and can be found in products like candy, chocolate, coffee creamer, cake decorations, chewing gum and even vitamin supplements. E171 is often used as coloring additive in foods, to lend the processed item a natural whiteness and opacity — such as in Skittles candy, where it's used as a white base to help give the candies their signature bright, colorful hue.

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Hemolysis was studied on suspensions of P25TiO2NPs (0.2 mg/mL and 0.02 mg/mL), vitaminB2@P25TiO2NPs (0.2 mg/mL and 0.02 mg/mL) and vitamin B2 (0.2 mg/mL and 0.02 mg/mL) were prepared and mixed with 500 μL of anticoagulated blood (donated by Laboratorio de Hemoderivados, UNC) in a rate of 1/10. A solution of NaCl 10% was used as the positive control and PBS as the negative control. Then, the samples were irradiated using the LED described above for 3 and 6 h to simulate the light penetration into the skin. Also, a set of samples was kept in the dark as control. Finally, the samples were centrifuged and the absorbance at 540 nm was measured in the supernatants. The experiment was reproduced twice; the standard deviation was calculated and p-value < 0.05 were considered significant.

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