Formulation Questions Answered

Here are the answers to your questions regarding your cosmetic formulation:

1. Your Formulation and Dissolving Issue

The formulation you attempted, combining Hyaluronic Acid (nano and standard), Glycolic Acid (AHA), and water, is possible in principle, but the concentrations and dissolving method you used are likely the cause of the issues.

• Dissolving Hyaluronic Acid: Hyaluronic Acid powder, especially the standard molecular weight, takes time to fully hydrate and dissolve in water to form a gel. Simply shaking for 5 minutes is usually not sufficient. The recommended method is to add the powder to the water, shake briefly, and then refrigerate for at least 3 hours (or longer) until the powder is completely dissolved and a clear gel forms. Shaking again during this period can help.
• Glycolic Acid Concentration: You used 9g of Glycolic Acid in a total of 100g (90ml water + 10g powders), resulting in a 9% concentration. For consumer cosmetic products, the recommended maximum concentration for AHA like Glycolic Acid is typically 5%, with a pH no lower than 3.5. Using 9% is generally considered for professional use under supervision and can cause significant skin irritation and sensitivity, especially at a low pH which is likely with this concentration of acid.

Therefore, the clumping is due to the Hyaluronic Acid not being fully dissolved using the correct method, and the formulation itself uses a Glycolic Acid concentration too high for typical consumer use.

2. Weighing Scale vs. Measuring Spoons

For accurate cosmetic formulation, especially when working with active ingredients like AHA or different types of Hyaluronic Acid where precise concentrations are important for efficacy and safety, a weighing scale is highly necessary. Measuring spoons measure by volume, and the density of powders and liquids varies, leading to inaccurate measurements by weight. Using a scale ensures you achieve the intended percentages of each ingredient, which is crucial for the stability, effectiveness, and safety of your product.

3. Using HA Standard and Cyclomethicone in Serums

• Hyaluronic Acid (Standard Molecule) is water-soluble and is suitable for use in water-based serums. It hydrates the outer layers of the skin and can help form a gel texture.
• Cyclopentasiloxane (Low-Odor Cyclomethicone) is a silicone oil and is not water-soluble. It is suitable for use in silicone-based or oil-based serums, or as part of the oil phase in emulsion-based products like lotions or creams. It provides a light, smooth, non-greasy feel and helps spread other ingredients.

You cannot simply mix Hyaluronic Acid (Standard) and Cyclomethicone together in a single-phase serum because they are not miscible (one is water-based, the other is oil/silicone-based). To use them in the same product, you would need to create an emulsion (like a lotion or cream) using appropriate emulsifiers to blend the water phase (containing HA) and the oil/silicone phase (containing Cyclomethicone). Alternatively, you can use them in separate serum formulations (a water-based HA serum and a silicone-based Cyclomethicone serum).

Remember to always include a preservative in any water-based formulation to prevent microbial growth.