Tuesday, March 8, 2011

Learning to formulate: What are cosmeceuticals?

I realized that I hadn't really addressed the concept of cosmeceuticals before diving right into the topic. This is partially because my brain has been addled by the stomach flu and partially because I didn't have 'net access for three days. So let's take a step back...

So what exactly are cosmeceuticals? There is no legal definition for these ingredients, but I found this definition, which I think works quite well. Cosmeceuticals are "cosmetic products with properties very similar to a pharmaceutical product (drug-like benefits)". (p. 295, Handbook of Cosmetic Science and Technology.) In other words, they are active ingredients we add to our products to offer a specific benefit, usually anti-aging. The problem is that there are no known proven ingredients that will reverse photo-aging, but we can include ingredients that will help reduce or slow down what we consider the signs of aging skin.

A note on this last sentence…Most of the tests done on these ingredients are done with skin cultures in a lab or with very small groups of women. We can say that the ingredients show promise, but not that they definitively stop or eliminate the signs of aging. Take a look at your favourite moisturizer commercial some time. You'll see that the disclaimers say things like "from women's reports after 28 days" or "subjective reports", not information on the clinic trials of the product. 

There are ingredients that have been tested extensively, like retinoids, AHA, salicylic acid, and anti-oxidants, and all of them show promise but aren't the magic bullet for removing every line and wrinkle from our skin. Clinical studies have shown very good results for plant anti-oxidants like the polyphenols in green tea (specifically the EGCG), soya isoflavones, tannins in pomegranate, and resveratrol in grape seeds. Other well studied anti-oxidants include Vitamin C, Coenzyme Q10, alpha-lipoic acid, and niacinamide.

Not all cosmeceuticals are exotic, expensive ingredients found only at specific suppliers. I'm sure you have a few in your workshop right now. Panthenol behaves as a hygroscopic ingredient, offering an improvement in skin's elasticity and cell regenerating features. Vitamin C offers anti-oxidant properties as well as stimulation of collagen synthesis in our skin. Soy bean oil contains isoflavones that can even skin tone and improve pigmentation. And think of all those lovely botanical extracts like green tea and grape seed that offer a ton of anti-oxidant benefits.

The problem in formulating with cosmeceuticals is that you must make sure that the lotion or serum or other product you are making is compatible with the cosmeceutical you wish to use. AHAs work best at a pH of 4.0, but you don't want to go below 3.5 if you are using esters in the mix or they will hydrolyze and smell really awful. But some of our preservatives and emulsifiers don't work well in fairly acidic environments. Some ingredients, like retinoic acid and Vitamin C, need to be kept in an opaque container away from oxygen, which is fairly difficult for large companies, let alone homecrafters!

If you really want to make moisturizers with cosmeceuticals, you will want to ensure you have a pH meter on stand-by and that you know your ingredients and how they interact with other ingredients very well. And you want to make sure you are using these ingredients at the recommended rates. It's always wise to stay within the formulating guidelines listed by the manufacturer or supplier because we don't want to waste our supplies, but in the case of ingredients like AHA or salicylic acid we want to make sure we aren't putting too many exfoliating or skin regenerating ingredients together in one place.

This is one of the reasons we want to be careful when combining extracts in our products. It's one thing to combine grape seed and green tea extract in the same product; it's another to combine papaya and white willow bark (two exfoliating ingredients). When it comes to cosmeceuticals, we can't be too careful. 

Okay, back to our regularly scheduled programming...


Pam said...

Hi Susan,

If the PH is incorrect would we add Stearic Acid? How would we know how much of an ingredient is needed to balance our PH?

Can you provide us with the model# of your PH meter? When I go to the website there are so many and they all look alike.



Susan Barclay-Nichols said...

Hi Pam. Stearic acid doesn't alter pH - it's a thickener. You'd add citric acid to alter pH. And it's hard to tell how much you'd have to use because it depends on the pH of the creation. In a surfactant based product, I found that 0.2% citric acid reduced the pH about 0.9, but that was only for that product and that recipe. You'll have to tinker with the amounts and see what works for the specific product in question. Start at 0.2%, test the pH, add another 0.2% if necessary, and so on.

I have the Jenco VisionPlus 630, but they have other models. Make sure you get right temperature model- mine measures fahrenheit, but I wanted Celcius! Check out the models at the Herbarie as they come with calibration fluid and other cool stuff!

terriblybadgrrl said...

I have a burning question about r-lipoic acid. Am going thru utter hell with it at moment. I've used the stabilized versions before, and tho ran into difficulties combining the RLA with other ingredients, it appeared that I'd managed to fully dislove and integrate it eventually.
But I've decided to purchase the pure form powder, so it's not stabilized and needs to be kept in the fridge.
Managed to desolve it, experimenting w/different solvents, but as soon as I attempt combining it w/other ingredients, it solidifies, and ends up the thickest goo, on the spatula.
What's worse, I can't reverse and save the darn goo. Once it solidifies, I can't deslove it at all again.
Is there anything you could possibly suggest? It's expensive stuff, as you might know. I'm now even wondering what it might turn to, once ingested. What if it just sticks to the walls of my intestines! Waiting to hear from purebulk, who I bought it from, but feeling rather hopeless as to a sulution...I'd be so very grateful if you might be able to help figure this out, please?

suki-san said...

terriblybadgrrrl: i know this is 37yrs late, but i thought others might have some thoughts on this subject also, for my edification, if nothing else!
So, i've also been wrestling w/rs-alpha-lipoic acid (not r-a-l a, like yourself, too spendy for me!)
1st of all, thank you for clarifying which of my ingredients was causing the undissolveable goobies i've been attempting to smoosh into solution. 2nd of all, i'm assuming you know that although a-l a is supposedly both hydro- & lipophilic, it plays much more friendly w/fats than w/waters, & is totally soluble in oils, especially slightly warmed oils..And, its also totally soluble in DMSO, (although, unfortunately, it smells exactly like pee, when mixed)..Its also soluble in ethanol (95% alcohol), although it starts to cake or powder up around the mouth of the bottle after awhile.
Pretty much the whole reason i'm posting on this topic is not b/c i have any real answers on the subject of seamlessly incorporating this substance into your concoctions, but b/c i'd love for Susan or any other bright, chemistry-oriented mind to put their amazing brains on it & devise some amazing work-around for doing exactly that, so i can learn how!
Actually, ANY little tidbit of data, in general, on this fascinating anti-oxidant, would be thoroughly helpful & thrilling to learn; especially anything useful re:the practical applications of, how to use & in what amount, which solvent is the best vehicle when trying to incorporate it into an emulsion! & so on..basically, only everything..
Its not like i haven't read every online study worth its salt, its the basic utility, in practice, that's eluding me..
If that's not too much to ask..
i lovelovelove your blog!, Susan, you are an inspiration to all of us science-minded readers, who, @ least for me, have yet to get off their butts & go get a degree, already!
Thank you so much for your brilliance & legendary open-source awesomeness! Best regards, suki