Serum Formulation with Salicylic Acid, Lactic Acid, and Copper Peptide

Regarding your proposed serum formulation with Encapsulated Salicylic Acid (6.6%), Lactic Acid (10%), and Sterile Water, and your question about using it with Copper Peptide, here is some information:

Your proposed formulation uses high concentrations of both Salicylic Acid and Lactic Acid. While these are effective exfoliating ingredients, combining them at these percentages can lead to significant skin irritation, redness, and sensitivity, especially for sensitive skin types.

Additionally, the type of Encapsulated Salicylic Acid is important. If you are using the Encapsulated Salicylic Acid (Liquid, Timed-Release, Wash-Off), this type is specifically designed for products that are rinsed off, not for leave-on serums. Using a wash-off ingredient in a leave-on product may not provide the intended benefits and could potentially cause issues.

Regarding the use of Copper Peptide with this formulation, it is generally not recommended to combine high concentrations of alpha hydroxy acids (like Lactic Acid) and beta hydroxy acids (like Salicylic Acid) with Copper Peptide in the same product. Copper Peptides are most stable and effective within a specific pH range, typically between 4.5 and 7.4. A serum containing 10% Lactic Acid and 6.6% Encapsulated Salicylic Acid (which is equivalent to 2% active Salicylic Acid for the wash-off type) will likely have a very low pH, well below the optimal range for Copper Peptide stability. This low pH environment can degrade the Copper Peptide, making it less effective or even inactive.

To safely and effectively use these ingredients, it is best to incorporate them into separate formulations or use them at different times of the day. For example, you could use the acid serum in the evening and a Copper Peptide serum in the morning, or alternate their use on different days.

When formulating with acids, always pay close attention to the final pH of your product to ensure both efficacy and minimize irritation. For Lactic Acid, using a neutralized form like Lactic Acid (AHA) Neutralized can help maintain a higher pH compared to the standard 90% concentration.

In summary, while the individual ingredients have beneficial properties, combining high concentrations of Salicylic Acid and Lactic Acid in a single serum can be irritating, and this acidic environment is likely to destabilize Copper Peptide. It is advisable to use these ingredients in separate products.