Modifying Serum Formula: Adding Centella Extract and Fixing Cloudiness

Subject: Serum formulation question, modifying Skinceuticals formula

Hello,

Regarding your questions about modifying the Skinceuticals-like Vitamin C serum formula by adding Centella Asiatica Extract:

1. Can Centella Asiatica Extract be added to the formula?
   Yes, it can be added. However, Centella Asiatica Extract is oil-soluble, while the base formula is water-based. This requires a suitable solubilizer or emulsifier to properly incorporate it. Also, as noted previously, the collagen-boosting benefits of Centella Asiatica may overlap with those already provided by Vitamin C.

2. Is the cloudy texture normal? If not, what caused it and how to fix it?
   No, the cloudy texture is not normal for a clear serum like the original Skinceuticals formula. It occurred because the oil-soluble Centella Asiatica Extract (and potentially the Vitamin E) was not fully dissolved or emulsified in the water phase. The amount of Laureth-23 in the original formula is likely insufficient to solubilize the added Centella Asiatica Extract.
   To fix this and achieve a clear serum, you need to use a more effective solubilizer.

3. How to make a clear serum that includes Centella Asiatica Extract?
   To make the serum clear, you should replace Laureth-23 with a suitable solubilizer like Flora Solve™ Clear.
   The recommended method is to mix the oil-soluble ingredients (Centella Asiatica Extract and d-Alpha Tocopherol Vitamin E) with Flora Solve™ Clear first until clear, and then add this mixture to the water phase.
   Based on your formula which includes 1% Centella Asiatica Extract and 1% Vitamin E (total 2% oil-soluble ingredients), you would need approximately 7-8% Flora Solve™ Clear to achieve clarity. If it is still cloudy, you can gradually increase the Flora Solve™ Clear concentration up to 9-10%.
   It is highly recommended to test this in a small batch first, as cloudiness is difficult to correct once the full batch is made.

Thank you.