Tinosorb S-Application in sunscreen

Bis-ethylhexyloxyphenol methoxyphenyl triazine, Product name also known as Tinosorb S, is a new type of broad-spectrum sunscreen. It was developed by Swiss ciba specialty chemical company. Tinosorb S has an absorption wavelength between 290-370nm, has good protection against UVA, and can absorb part of UVB[1]. It has good light stability and is not easily absorbed by the skin.

In addition, Tinosorb S has a relatively large molecular weight, has strong photostability, is not easily absorbed by the skin, and does not have estrogen activity, so it has high safety and has been approved by the European Medicines Agency[2]. The sun protection band is very wide, the maximum absorption peak is at 342nm, after 370nm, the absorption is poor. Tinosorb S has high absorption efficiency, and a small amount will have a good effect of improving sun protection. Fat-soluble Tinosorb S has excellent compatibility with other sunscreens, a versatile ingredient, and will not be damaged by other ingredients stabilizing effect[3]. Tinosorb S is an indispensable substance in sunscreen.

When sunscreens are exposed to sunlight, photons in the ultraviolet rays collide with a pair of electrons in the sunscreen molecules. Molecules in the ground state absorb the energy of the photon, so they transition to the singlet excited state, freeing them from the constraints of the atom. Some excited molecules relax by radiation, return to the ground state after releasing photons, and emit fluorescence[4]; There are also some excited molecules that stay for a while and then return to the ground state through radiation-free relaxation[5]. The energy is dissipated in the form of heat by internal molecular isomerization and vibration relaxation, and some generate phosphorescence[6]. The sunscreen molecules returning to the ground state can continue to absorb photons in the ultraviolet[7]. In this way, Tinosorb S sunscreen absorbs and releases the energy of photons and prevents the skin from absorbing the energy in the sun.

References

[1] L. Dencausse, A. Galland, J. L. Clamou. Validation of HPLC method for quantitative determination of Tinosorb?S and three other sunscreens in a high protection cosmetic product[J]. International Journal of Cosmetic Science, 30(5):373-382.
[2] Kim, Sung Ho, Debnath, Dipen, Geckeler, Kurt E. Nanopumpkins and a sunscreen agent: the inclusion complex of cucurbituril and Tinosorb S[J]. Supramolecular Chemistry, 23(5):337-341.
[3] Arrandale V H, Liss G, Tarlo S M, et al. analysis of Occupationally-related Positive Patch Test Results in the 2001–02 North American Contact Dermatitis Group Canadian Data[J]. 2009, 21(4):185.
[4] Souza C, Pmbgm C. Development and photoprotective effect of a sunscreen containing the antioxidants Spirulina and dimethylmethoxy chromanol on sun-induced skin damage[J]. 2017, 104(2):52.
[5] Verena Schleyer, Oliver Weber, Amir Yazdi. Prevention of Polymorphic Light Eruption with a Sunscreen Very High Protection Level Against UVB and UVA Radiation Under Standardized Photodiagnostic Conditions[J]. Acta Dermato Venereologica, 2008, 88(6):555-560.
[6] https://www.chemspider.com/Chemical-Structure.10645286.html?rid=328f4358-b621-4a88-89d4-bfe51950862c&page_num=0
[7] https://pubchem.ncbi.nlm.nih.gov/compound/135487856