the eternal search for PEG-free solubilizer

Till now the best and most widely used solubilizers are Polysorbate (specially Polysorbate-20, known as well as Tween-20 with CAS#9005-64-5) and PEG-40 hydrogenated castor oil with CAS#61788-85-0. Both of which containing PEG in the molecule.

I personally have nothing against PEG-containing ingredients in pharmaceuticals and cosmetics. They are (at least in the EC) declared on the package and it is up to the consumer if he chooses the product or not. Actually, PEG-derivatives are inherently nontoxic, do not bite and are noncarcinogenic. It's the byproduct of the ethoxylation process, "1,4-Dioxane" which is a known carcinogen. This byproduct should however be filtered out of the product or shall not be produced at all during a scrupulous and technically well-managed ethoxylation process.

(1,4-Dioxane is limited to max. 50 ppm in raw material and 10 ppm in end products in the EU, FDA hast no limitations on this by product). 

For my personal products and for those customers who do not strictly wish to have PEG-free ingredients in their recipes, I apply PEG-containing ingredients provided by known and serious providers with a clear conscience.


Nowadays however, with the increasing demand of the consumer for PEG-free ingredients and products (at least in Japan, western Europe, USA and Canada) it is important to find a broadspectrum substitute for PEG-containing solubilizers.

There are but little, if any at all, possibilities to incorporate oil soluble ingredients such as essential oils, perfume oils or other oil soluble active ingredients (alpha-bisabolol for example) in aqueous solutions such as skin and hair tonics, perfumes, room fragrances, etc.

One of the most praised PEG-free solubilizers which is recommended in some specialty forums was Dermofeel ® G 10 L from Dr-Straetmans (INCI:Polyglyceryl-10 Laurate) and it's diluted variation Dermofeel ® G 10 LW, which is already mixed with water. After I read a few reports and saw recipes made with it, I bought a small sample from a retail supplier and have tried all known to me tricks to prepare a facial tonic with 1% of an essential oil. It was really disappointing as I did not succeed. 

I've asked myself, why people write recipes which do not work, whether they really have touched any of the ingredients they mention in their recipes, or whether they copy recipes, exchange a couple of ingredients and concentrations and disclose it as their own recipe without even have touched a spatula?

Anyway,since Dermofeel ® G 10 L is mentioned on the homepage of the manufacturer as a solubilizer as well, I contacted them and asked for a tip. I was informed: this ingredient is not suggested as a substitute for PEG-40 hydrogenated castor oil and can not have the same performance and efficacy.


The company has suggested another ingredient (mixture) as a solubilizer, comparable to PEG-40 hydrogenated castor oil and sent me samples and test results. And it worked.  

The solubilizer has a lower viscosity and an intensive yellow color in comparison to PEG-40 hydrogenated castor oil. The yellow color would appear in end product by higher concentrations.

On the photo you can see a simple body splash with 1% of a fragrance oil. 4% of PEG-40 hydrogenated castor oil were enough to solubolize FO in comparison to 8% in case of the PEG-free solubilizer. Higher needed concentrations, the higher price and the yellow color are the main disadvantages of that ingredient. However, according to the manufacturer, the min. needed concentration is very dependent on the nature of FO or EO and there are some case in which the concentration is similar or even lower in comparison to that of the traditional solubilizer. 


We are working further on that solubilizer, trying to optimize its application in our own products. We plan to apply it in SKINChakra® products after all tests are completed successfully, and are going to offer it on our online Shop (expectedly from October) to other cosmetics-crafters.

This solubilizer, is which is called Symbiosolv® XC is a commodity blend:

Caprylyl/Capryl Wheat Bran/StrawGlycosides, Aqua, Fusel Wheat Bran/Straw Glycosides, Polyglyceryl-5 Oleate, Sodium
Cocoyl Glutamate, Glyceryl Caprylate.

24.07.12
Correction and Supplement:

After I wrote this post, I received lots of comments in other blogs and forums, until a nice crafter revealed her success to me. I emphasized on applying max. 10% of Ethanol. With this low concentration, Dermofeel ® G 10 LW is really ineffective as a solubiliser. From 20% Ethanol upwards it works as a solubiliser.