There has been some confusion about the difference between Ascorbyl Tretaisopalmitate and Tetrahexyldecyl Ascorbate.

There is no difference!

Ascorbyl Tretaisopalmitate and Tetrahexyldecyl Ascorbate are the same product with a different name.

Tetrahexyldecyl Ascorbate is a colorless to pale yellow liquid.  Its CAS number is 183476-82-6 (CAS# 183476-82-6). Its INCI name is Tetrahexyldecyl Ascorbate (INCI: Tetrahexyldecyl Ascorbate) and its chemical name is Ascorbyl Tetraisopalmitate (Chem. Name: Ascorbyl Tetraisopalmitate).

What is Tetrahexyldecyl Ascorbate?

Tetrahexyldecyl Ascorbate is a very stable, oil-soluble Vitamin C ester which has anti-oxidant activity, inhibiting lipid peroxidation. Topical use can mitigate the damaging effects of UV exposure. Studies have shown it to stimulate collagen production as well as clarifying and brightening the skin by inhibiting melanogenesis (the production of pigment) thereby promoting a more even skin tone. Unlike ascorbic acid, it will not exfoliate or irritate skin.

How do I use Tetrahexyldecyl Ascorbate?

Tetrahexyldecyl Ascorbate is one of the easiest skin care actives to use in DIY skin care.  It can be added to any cream or lotion, and it is also the key ingredient in an Anhydrous C product.  I wrote a previous post about Anhydrous C  ( l-ascorbic acid and Tetrahexyldecyl Ascorbate in a silicone base) here: http://bulkactives.com/blog/index.php/2009/11/anhydrous-c-for-skin-care-absorption-of-l-ascorbic-in-a-silicone-base/

Dimethyl Isosorbide (DMI) is a high purity solvent and carrier which offers a safe, effective delivery enhancement mechanism for active ingredients in personal care products. Sunless tanners, facial and eye-zone treatments, skin serums, anti-acne formulations and make-up removers are just some of the products whose performance can be improved with the use of Dimethyl Isosorbide (DMI) in formulation. In addition to improving performance, its use as an epidermal penetration enhancer can allow formulators to reduce the amount of actives required to achieve effects, resulting in reduced formulation costs, and lower skin irritation with aggressive active ingredients.

Active ingredients for skin care formulations are only as effective as the delivery system. The more efficient the delivery system, the more likely it is that the active ingredient will perform as intended. Consider all of the benefits made possible by Dimethyl Isosorbide delivery enhancer, a safe carrier ingredient proven to place active ingredients where they are needed most on skin. A water-white liquid with excellent solvent properties,Dimethyl Isosorbide offers formulators the option to boost the penetration of actives in the epidermis layer of skin, enabling targeted delivery for products such as self-tanners, anti-acne treatments and more.

Consumers of skin care products will notice the difference in products formulated with a delivery enhancement agent. Test results show that Dimethyl Isosorbide contributes to fast color development of sunless tanner, with less streaking and longer lasting tan as compared with self-tanner products without the carrier ingredient. In other specialty products, such as eye-zone treatments, skin serums, scalp treatments, Dimethyl Isosorbide may be used to enhance skin penetration. The unique solvency properties of Dimethyl Isosorbide boosts performance of formulations such as make-up removers.

The skin care formulators’ performance booster

Ask consumers why they use a skin care product and chances are good they will purchase one they perceive to be effective. Formulators can improve the odds that an active ingredient will work to the benefit of the consumer in products designed for skin treatment. With Dimethyl Isosorbide, the formulator can enhance the delivery of active ingredients without having to add more active. Effective delivery of actives such as salicylic acid, Vitamin C, lactic acid, hydrocortisone and hyaluronic acid can even reduce the active ingredient concentration requirement, serving to reduce the formulation cost of finished products.

Other benefits of Dimethyl Isosorbide:

• Dimethyl Isosorbide offers enhanced penetration of actives to the epidermis, enabling targeted delivery.
• Dimethyl Isosorbide provides a lower level of skin irritation with a reduction in the required concentration level of aggressive actives.
• Dimethyl Isosorbide gives improved formulation shelf stability, including those susceptible to hydrolysis and transesterfication.
• Dimethyl Isosorbide has miscibility with most organic solvents and non-ionic surfactants.
• Dimethyl Isosorbide allows incorporation within many product forms, including clear gels.
• Dimethyl Isosorbide has a long history of safe usage.
• Dimethyl Isosorbide has the ability to transport water soluble actives into skin, without recrystallization of the active.
• Dimethyl Isosorbide has the ability to produce formulations with standard equipment, without the need for flammable materials handling.

Buy Arlasolve DMI / Dimethyl Isosorbide

Recent posts on various DIY skin care forums have discussed the issue of the penetration of L-ascorbic acid suspended in a silicone base into the skin.

More precisely, a few posters have started promoting the idea that L-ascorbic acid cannot penetrate into the skin, because silicone forms a barrier on the skin.

I would like to address this issue in more detail.

Background: Stable L-ascorbic acid products for skin care

The DIY skin care community has long struggled with the formulation of a stable L-ascorbic acid skin care product. In fact, professional skin care companies and formulators have also struggled with the same problem.

Some attempts have been made by professionals to develop a stable vitamin C skin care product.  The best example of this is the Skinceuticals C+E+Ferulic product.  This is based on the 2006 study “Ferulic acid stabilizes a solution of vitamins C and E and doubles its photoprotection of skin” by Pinnel and others.

This study claimed that

“Ferulic acid is a potent ubiquitous plant antioxidant. Its incorporation into a topical solution of 15% L-ascorbic acid and 1% tocopherol improved chemical stability of the vitamins (C+E) and doubled photoprotection to solar-simulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation.” http://www.nature.com/jid/journal/v125/n4/full/5603565a.html

However, consumers have found that skinceuticals C E ferulic product is often orange tinted.  This color usually indicates that the L ascorbic acid has oxidized, thus making it pro-oxidant.  So, even though Ferulic acid may stabilize l ascorbic acid in the lab, in practicality there appear to be some serious issues that have not been addressed.

DIY skin care formulators are able to work around this.  By making a CE Ferulic product at home, it is possible to have a fresh supply every week, thus reducing (but not eliminating) the amount of vitamin C oxidization.

Solution: The Fitzpatrick study

Another study of interest is the 2002 “Double-blind, half-face study comparing topical vitamin C and vehicle for rejuvenation of photodamage” by Fitzpatrick.

Even though this study predates the CE+Ferulic study, it did not start getting discussed on the DIY skin care forums until quite recently.

Fitzpatrick’s method was as follows:

“Ten patients having facial photodamage were recruited for a double-blind pilot study of a newly formulated vitamin C complex having 10% ascorbic acid, a water soluble acid, and 7% tetrahexyldecyl ascorbate, a lipid soluble analog.

Both of these are combined in an anhydrous polysilicone gel base, which acts as a ‘dermal patch,’ releasing the water soluble acid slowly and the lipid soluble analog rapidly. The active vitamin C complex was applied to one side of the face and the inactive placebo base was applied to the opposite side of the face once a day.” http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=11896774&query_hl=7&itool=pubmed_ExternalLink

Now, this is where a very few posters start having some issues.  The base used is an anhydrous silicone gel, and the doubt seems to be in the fact that a very few posters believe that silicone forms a barrier and therefore hinders the absorption of active ingredients.

However, let’s look at the next part of Fitzpatrick’s study:

“Biopsies showed increased Grenz zone collagen, as well as increased staining for mRNA for type I collagen. This formulation of vitamin C results in clinically visible and statistically significant improvement in wrinkling when used topically for 12 weeks. This clinical improvement correlates with biopsy evidence of new collagen formation.”

Now, if silicone prevents the absorption of active ingredients, than there would not have been an increase collagen.

So, this should put to rest the claims that using silicone as a base prevents the absorption of active ingredients.

Flawed study

There is one troubling aspect about the Fitzpatrick study.  The study did not test the use of each key ingredient separately.

The two key ingredients in the anhydrous C product are L-ascorbic acid (which is water soluble), and Ascorbyl Tetraisopalmitate (also known as Tetrahexyldecyl Ascorbate ) which is oil soluble.

So, even though the study shows that the combination the two active ingredients in a silicone base led to an increase of collagen, we do not know if this was caused by the Tetrahexyldecyl Ascorbate, the Vitamin C, or the combination of the two.

This brings us back full circle to the original problem! We do not know which active is responsible for the increase in collagen. So it is possible to claim that the L-ascorbic acid is in fact not absorbed by the skin, and that the increase of collagen is cause by the Tetrahexyldecyl Ascorbate.

The blame for this confusion can be put purely with Fitzpatrick. It seems a simple matter to have tested the activity of both l-ascorbic and Tetrahexyldecyl Ascorbate in anhydrous silicone, separately. However, he chose not to do this.

So, we remain with his original statement.

“Both of these are combined in an anhydrous polysilicone gel base, which acts as a ‘dermal patch,’ releasing the water soluble acid slowly and the lipid soluble analog rapidly.”

To me the dermal patch idea makes sense, and I personally put more trust in this than the doubt caused by a very few (but very ‘vocal’) posters on skin care forums.

In the end the choice is yours.

I will continue to use the anhydrous C product as my number one weapon in anti aging skin care.  Why? Because no matter which active did the job, somehow this product has improved my skin and that is ultimately what I want.

http://www.bulkactives.com/siliconegel.htm

http://www.bulkactives.com/ascorbicacid.htm

http://www.bulkactives.com/ascorbyltetraisopalmitate.htm

I recently read a post on another forum, and was slightly annoyed that an email I wrote about one of my recipes was either not understood or quoted out of context, or maybe I was not clear enough in my answer.

So, let me explain.

Ferulic acid is soluble in an alcohol.

I know that some people claim they have dissolved it in water of glycerin, but I wonder if they confuse ‘well dispersed’ with ‘dissolved’. There is a big difference, but because Ferulic acid is such a very fine powder it may be hard to physically tell the difference.

Now, what alcohols are suitable for dissolving Ferulic acid?

In my recipe I suggest ethanol or Propylene Glycol. My recipe does not suggest denatured alcohol, and I also do not suggest that people buy this.

There is a difference between ethanol and denatured alcohol.

“Ethanol, is also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol.” http://en.wikipedia.org/wiki/Ethanol

“Denatured alcohol is ethanol that has additives to make it toxic, unpalatable, or otherwise undrinkable. In some cases it is also dyed.” http://en.wikipedia.org/wiki/Denatured_alcohol

My recipe clearly states to use ethanol. One customer wrote that she bought ethanol, and got a bottle of denatured alcohol. This is an issue between her and the supplier she used. I suggested that she contact her supplier to verify what it was she actually ordered and received.

I personally can buy NON-denatured  ethanol where I live, so it is a non-issue for me. However, in some countries this product is not available. In the USA people could buy Everclear (if available in your state), or you can simply use a high alcohol content VODKA.

Regarding the use of alcohols in skin care products.

I am well aware that a particular supplier makes a big deal out of this.

On their product pages they clearly state the solubility of their powder IF it is water or oil soluble.

If it is not, then there is no solubility info displayed, but they then claim that “The powder will not dissolve immediately, but will release components slowly into the cream/lotion.”

I think that this is a ridiculous claim to make, but it most definitely does help sell all their powders.

What really cracks me up is when I look at the ingredient listings for some of their ready-to-use products. Here we can see that they do actually use alcohol related compounds, mainly Butylene Glycol ( http://en.wikipedia.org/wiki/Butylene_glycol ).

For example, in the infamous ‘Canvas base cream’, it is the 4th ingredient in the listing (although they claim it is used for ’slip’).

So, rant over.

In short, if you want to use actives that are alcohol soluble then use NON-denatured  ethanol, Everclear, or vodka. DO not use denatured alcohol.

If you don’t want to use any alcohol in your skin care products, then do not buy powders that only dissolve in alcohol.

If you want to try alternative solvents, like glycerin, please make sure that the powder has actually dissolved, not just well-dispersed.

I sometimes get emails asking me about the purity of our products.  This is usually because of names like ‘Green Tea extract (standardized for 90% EGCG)’ or ‘Resveratrol 98%.’

There appears to be some confusion with these percentages and it appears that some people believe that our products use ‘fillers’ and are therefore no good.

Let me explain this

If someone emails me and asks “Are your products pure?” then the answer is “YES.”

They are pure, because we do not add any fillers.  So, that means when you buy our Grapeseed extract, it is 100% Grapeseed extract, NOT 60% Grapeseed extract and 40% red colored flour.

What about those percentages?

The percentages indicate the amount of the active ingredient in the powder.  For example, the active ingredient we want in Grapeseed extract are the Proanthocyanidins.

So, when you see the name Grapeseed extract 95% Proanthocyanidins, then you know that the active is 100% pure Grapeseed extract and that it has been standardized for 95% Proanthocyanidins.

The term used to show you this is the assay (http://en.wikipedia.org/wiki/Assay), we list the assay for all our products on each product’s page.

Why do we sell products that are standardized for 70% or 95%, why not 100%

Well, the more a plant extract is standardized, the more expensive the manufacturing process.  This REALLY makes a big difference.  For example, White Willow Bark extract is standardized for 25.23% Salicin, it costs hundreds of dollars per KG. It is also possible to buy the same product standardized for 95% Salicin, but that will cost THOUSAND of dollars per KG.

So, sometimes it is prohibitively expensive to buy plant extracts that are standardized at a high percentage.

We therefore buy products that are standardized at as high a percentage as possible, while at the same time keeping the price reasonable.

I really do not think you would be willing to spend US$80 for a gram of White Willow Bark 95%, especially when it is easier, a lot cheaper, and just as effective to use Salicylic acid (BHA).