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Stabilize Vitamin C
Hello,
I’m trying to stabilize Vitamin C in a serum, I’ve already made which seems like ten failed bench samples… Any suggestions???ThanksMindy -
40 Replies
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Keep it away from oxygen and water…
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This isn’t an easy problem to solve. Like Robert says, make an anhydrous formula.
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Yes, I’ve been trying for awhile to do this and have had no success thus far. My formula now consist of no water and it only last about 7-10 days before it starts to turn really yellow. Is there any chemicals that have been shown to help stabilize Vit C at all? How do the big companies get a 20% stabilized Vit C serum but so many people can’t figure it out? Or is the question maybe that it’s not being stabilized but consumers really don’t know the difference anyway? I’ve seen my share of bad, terrible and plan shouldn’t be on the shelf cosmetics.
Also, would a nitrogen puff before induction sealing help keep shelf life of my Vit C formula? -
L’oréal (Skinceuticals) stabilizes vitamin C with ferulic acid and vitamin E. But theirs serums still oxidize easily. You buy them with a champagne color and after some days they are brownish.
What about using vitamin C derivatives, like magnesium ascorbyl phosphate? -
I think it the reality is that consumers can’t tell a difference whether their vitamin C is oxidized or not. All that matters to people is that they are putting something on their skin that says Vitamin C. The things that make the formula actually work (moisturizers, occlusive agents, etc) are what’s responsible for whether people like a product or not.
For the most part, unless you’re getting a prescription dose of Retinol, vitamins in cosmetic products have no effect on the results. At least I haven’t seen any real-life evidence that they do. -
why not use ascorbyl tetraisopalmitate instead?
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I agree with Perry, but the the combination of ascorbic acid (vitamin C) + ferulic acid + tocopherol in the right pH can help protect your skin from the sun:
Vitamin C also has an anti-melanogenic effect, so can help to diminish spots… -
@pma - Interesting studies. They were pretty small though <20 subjects in them all and they didn’t provide an adequate control in my view.
They did what many people do when investigating cosmetic products / ingredients. They missed the most important control.In these studies, the question isn’t whether Vitamin C can protect skin from the sun, the question is can Vitamin C protect skin from the sun better than the best technologies (e.g. traditional sunscreens). Since they didn’t include them, I’m guessing the answer is ‘no’.Therefore, for a formulator the best strategy would be to create a sunscreen using traditional sunscreens and add a drop of Vitamin C to make the claim that it is in there. -
I looked down that path but derivatives but get mixed results in how effective they are compared to L-ascorbic acid. Well I guess if I figure it out, I’ll be keeping my process ultra secret!
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I believe that the use of Vitamin C with Ferrulic acid is protected under patent.
I have had good luck with an anhydrous formulation based upon silicones. The ascorbic acid is soluble in PEG-8. The background for the Formulation is outlined in a C&T Article from 2006.
https://drive.google.com/file/d/0BwuqL_fQzYhiZjB5SFFDZ2JaU3c/edit?usp=sharing
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I don’t want to hijack the discussion, but I’ve seen so many offers over the internet of Vitamin C/Ferulic acid serums and I wonder how they get around the patent issue. Are they too small and fly under the radar? or, they use less than 0.2% of ferulic acid or its derivative, which is the lowest concentration claimed by the patent.
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I’ve read the patent. My question is how people/companies avoid infringing the patent.
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They stay under the radar I believe. Perry has some experience with patents so he may be able to better respond.
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Staying under the radar is one method. It is up to patent holders to track down infringers if they want to collect damages. As you can imagine, this could be costly.
More reputable companies just use amounts of the ingredient outside the concentration range. -
I had this problem recently with an Aloe Vera juice dietary supplement I developed for a customer. Everything looked fine on the shelf ( quickest way to see if anything goes wrong was to put on a shelf in bright sun… Mould shows up very quickly).
Sent this away for preservative efficacy tests and 3/4 products came back fine. The fourth passed after a tweak to the preservatives.So, we felt fine to release for sale whilst doing on-going stability.
Under accelerated stability the Vit C disappeared within hours in three of the four product. The fourth was still there but lower than the levels claimed.
The difference between the fourth product and the others was addition of Vitamin E (dl-alpha tocopheryl acetate).
The quickest solution to the problem was to add vitamin E to all products and increase the overage of the vitamin C by 120%. Ie 90 mg/serve claimed input amount was 198 mg/serve.
Admittedly I was working with pharmaceuticals rather than cosmetics, but I am sure there will be a cross-over of information that could be useful. We did consider using Ferulic acid, but we wanted a solution that didn’t require product relisting.
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You started selling a product before you knew it was stable and possibly with a compromised preservative system?
The lack of regulation in the dietary supplement industry in the US unsettling.
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Barnet Products sells a stabilized form of vitamin C but I think it is oil soluble. They refer to it as BV-OSC and it is Tetrahexyldecyl Ascorbate, CAS #: 183476-82-6
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Hi Perry,
I think I may not have been clear. We knew the preservation system was fine - that had been tested using preservative efficacy tests and 3 month accelerated stability to give 9 month shelf-life before the product went on sale. There has been on-going accelerated stability with each batch to ensure we can push this out to 36 months safely.
We were tweaking the vitamin C levels based on the claims to ensure it could be assayed to the claim levels. This is normal practice under TGA (Australia) to conduct on-going stability to ensure compliance.
I cannot comment on the US dietary supplement industry. There are different regulations to be dealt with.
Under Australian Dietary Supplements regulations, they come under the same regs as pharmaceuticals and cosmetics and compliance is defined in law.
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@Herbnerd - thanks for the clarification!
It’s good to hear some countries take dietary supplement regulation seriously. In the US, it’s pretty much anything goes as long as no one can prove you’ve killed someone. -
After Mark’s suggestion about using an anhydrous system to preserve vitamin c, I found this serum with vitamin c and caffeic acid that contain the following ingredients (I copied exactly as they were listed):
Cyclomethicone (slip agent), Dimethicone Crosspolymer-3, Ascorbic acid (antioxidant), Dimethicone (slip agent), Bis-vinyl Dimethicone/Dimethicone Copolymer (slip agent), Tetrahexyldecyl Ascorbate (antioxidant), Tocopherol (antioxidant), Caffeic acid (antioxidant).
I assume ascorbic acid and caffeic acid are not soluble in silicone at all, so I wonder how they were incorporated into the serum. Are they just in suspension?
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Think either they have omitted something critical or as Robert generally says it is not a complete ing list. If the product is hazy and thick then they have simply suspended them into silicone gel.
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The product will be just a suspension. The silicones will be very good at keeping water & air out and nothing in there that the ascorbic acid will react with.
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@alchemist Excellent point
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I just found that they claim the ascorbic acid is “encapsulated” in dimethicone copolymer??
Look down in the Comments section
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