Thanks for the concise and entertaining short! Was a little surprised that more of the chemistry aspects of sunscreen weren't covered given how in-depth others in the series are. My students were always so focused on the chemistry of bad breath and acne videos, but I think this video didn't quite have the impact those did. There is all sorts of fascinating nano-tech issues with some of the new sunscreens... Still, great work and VERY much appreciated!!! Thanks so much!
You've got the substances wrong, it's the Avobenzone which absorbs UV-A. It also absorbs some UV-B, but that causes the molecule to break down into derivatives of benzoic acid and acetophenone. And that's where the UV-B filter comes in. Not only it absorbs UV-B to protect the skin, but also to protect the UV-A filter. That's also why you can get UV-B-only filter, but not a UV-A-only, unless it's a scattering (a.k.a. physical) filter like TiO2, which would not degrade upon UV exposure.
thank you for the clarification..You are correct, but, I did not find that Avobenzone which blocks UVA (1) has any UVB blocking coverage... Mark Sibley,M.D.
Does homosalate, Octycrylene and octisalate go together with Uvinal A and Tinosorb M? I ask because I put a tinted spf over a Korean PA+++ and I don’t want to affect the effectiveness. I ask because I use the Korean sunscreen Beauty of Joseon and then I put IT cosmetics cc cream, SPF 40 over the top.
this is a nice ''primer'' on sunscreens and the way they work and the ingredients and the difference...The listing at 1:56 was incorrect.The 2 items were switched as to which blocked UVA(1) =Avobenzone...and which blocked UVB =Octinoxate (which, by the way, harms the oceans, especially coral reef death)...And finally, Zinc Oxide is the better and safer UVA(1+2) blocker, compared to Titanium Dioxide which only blocks UVA(2) and also has been found to harm the coral reefs... Mark Sibley,M.D.
a completely new kind of sunscreen that lasts more than a month could be based on a thing like transparent Henna. A chemical at henna does a Michael reaction with the keratin protein of skin and links a colored molecule to it durably, not washing off. There are molecules that do the Michael reaction that are transparent. Linking that michael reaction group to a UV absorber then makes a sunscreen that lasts longer than a month. This could be a completely new anti-photoaging product as a new revenue product. Notably, the UV absorbers in commercial sunscreens last only a few hours, but, fortunately, the UV absorbers in printing inks lasts months. Those chemicls could be tested to find out which are body harmless, and be a part of the michael reaction sunscreen that lasts longer than a month. This is a complimentary public domain idea and can be commercially developed without further contact 7/29/23 Treon Verdery, North Bend, Oregon
Thanks for the concise and entertaining short! Was a little surprised that more of the chemistry aspects of sunscreen weren't covered given how in-depth others in the series are. My students were always so focused on the chemistry of bad breath and acne videos, but I think this video didn't quite have the impact those did. There is all sorts of fascinating nano-tech issues with some of the new sunscreens...
Still, great work and VERY much appreciated!!! Thanks so much!
You've got the substances wrong, it's the Avobenzone which absorbs UV-A. It also absorbs some UV-B, but that causes the molecule to break down into derivatives of benzoic acid and acetophenone. And that's where the UV-B filter comes in. Not only it absorbs UV-B to protect the skin, but also to protect the UV-A filter. That's also why you can get UV-B-only filter, but not a UV-A-only, unless it's a scattering (a.k.a. physical) filter like TiO2, which would not degrade upon UV exposure.
thank you for the clarification..You are correct, but, I did not find that Avobenzone which blocks UVA (1) has any UVB blocking coverage... Mark Sibley,M.D.
Does homosalate, Octycrylene and octisalate go together with Uvinal A and Tinosorb M? I ask because I put a tinted spf over a Korean PA+++ and I don’t want to affect the effectiveness.
I ask because I use the Korean sunscreen Beauty of Joseon and then I put IT cosmetics cc cream, SPF 40 over the top.
this is a nice ''primer'' on sunscreens and the way they work and the ingredients and the difference...The listing at 1:56 was incorrect.The 2 items were switched as to which blocked UVA(1) =Avobenzone...and which blocked UVB =Octinoxate (which, by the way, harms the oceans, especially coral reef death)...And finally, Zinc Oxide is the better and safer UVA(1+2) blocker, compared to Titanium Dioxide which only blocks UVA(2) and also has been found to harm the coral reefs... Mark Sibley,M.D.
a completely new kind of sunscreen that lasts more than a month could be based on a thing like transparent Henna. A chemical at henna does a Michael reaction with the keratin protein of skin and links a colored molecule to it durably, not washing off. There are molecules that do the Michael reaction that are transparent. Linking that michael reaction group to a UV absorber then makes a sunscreen that lasts longer than a month. This could be a completely new anti-photoaging product as a new revenue product. Notably, the UV absorbers in commercial sunscreens last only a few hours, but, fortunately, the UV absorbers in printing inks lasts months. Those chemicls could be tested to find out which are body harmless, and be a part of the michael reaction sunscreen that lasts longer than a month. This is a complimentary public domain idea and can be commercially developed without further contact 7/29/23 Treon Verdery, North Bend, Oregon
TROLLLLLLLLLL!!!!!!1
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