How Active Is Your Surfactant?

Dear Valerie: How do you approach calculating active surfactant matter of a product? What do you do when a supplier gives vague information (i.e. 29-35%)?  —Kate Ionic

Dear Kate:

The calculation of active surfactant matter in a cleansing preparation is useful to determine the cleansing or irritating potential of your product. For those unfamiliar, active surfactant matter, or active content, is calculated by taking the percentage of the surfactant used in your formulation and multiplying that by the percent of active matter disclosed in the surfactant used.

For example, if Cocamidopropyl Betaine (CAPB) contains 28% active content, and your formula contains 12% CAPB, you effectively added 3.36% CAPB to your formulation. The rest of the 12% is water, sodium chloride, glycerin, or whatever other by-products are contained within. You would do this calculation for each surfactant.

You can find the active content on a technical datasheet or specifications for the raw material…if you’re not looking at active matter, you should be!

While active matter is provided in a range, the intent is not done to be secretive or intentionally vague. The reality is there is a need to account for lot-to-lot variation in a batch of given surfactant, much like product specs have ranges.

The range provided should be sufficient for your theoretical needs. After all, you will have a theoretical range of active matter! When I worked at a large salon brand, where we were shampoo kings, we were never concerned with the range values provided by suppliers. When you take into consideration surfactant use level, the in-use range ends up not being a smaller variation. And your active matter in the final product should be a range.

On occasion we needed to get specific, so we reviewed certificates of analysis from the lots we historically purchased. This gives a good indication of what the manufacturer realistically produces. It may be in the center of the range, or it may be at one of the ends. However, it’s usually not all over the place. Evaluating the COA gives you a pretty great starting point for calculating your active matter.

If you have not actively used the material in the past, you can always request the historical data from the manufacturer or ask where they typically are in the range of active surfactant matter. 

Valerie George

askvalerie@icloud.com

Valerie George is a cosmetic chemist, science communicator, educator, leader, and avid proponent of transparency in the beauty industry. She works on the latest research in hair color and hair care at her company, Simply Formulas, and is the co-host of The Beauty Brains podcast. You can find her on Instagram at @cosmetic_chemist or showcasing her favorite ingredients to small brands and home formulators at simply-ingredients.com