Ingredient Compatibility and pH Stability in Galactomyces Serum Formula

Question

I am formulating a serum using Galactomyces as a base, including ingredients like Magnesium Ascorbyl Phosphate, Hi-EGCG, Licochalcone A, and Zinc PCA. Are these ingredients compatible, and will the formula be stable and effective, considering the different optimal pH ranges for Magnesium Ascorbyl Phosphate (pH 7-9) and other actives (pH 6-7)?

MySkinRecipes Expert · Accepted Answer

Regarding the compatibility of the ingredients in your proposed formula using Galactomyces as a base:

Most of the ingredients you listed are generally compatible with each other. However, the main challenge lies with Magnesium Ascorbyl Phosphate (MAP).

MAP is most stable and effective in a slightly alkaline pH range (pH 7-9).
Many of the other active ingredients in your list, such as Hi-EGCG, Licochalcone A, Zinc PCA, and others, typically perform best and are more stable in a slightly acidic pH range (pH 6-7).

Formulating all these ingredients together in a single product makes it difficult to achieve the optimal pH for all actives simultaneously. If you adjust the pH to be optimal for MAP (alkaline), it may reduce the efficacy or stability of the other ingredients. If you adjust the pH to be optimal for the other ingredients (slightly acidic), MAP may not be stable or effective.

Therefore, while the ingredients might not cause immediate precipitation or flaking upon mixing, achieving the full intended benefits from all actives in a single formula with this combination, particularly due to the pH conflict with Magnesium Ascorbyl Phosphate, is challenging. You might consider using a different Vitamin C derivative that is more stable at a slightly acidic pH, or formulating these ingredients into separate products.