C E Ferulic Serum Formulation Guidance

Based on your list of ingredients for a C E Ferulic serum, here is some guidance, particularly regarding the type of hyaluronic acid to use and information on the other components.

Hyaluronic Acid Selection

For a serum, using a combination of different molecular weights of hyaluronic acid is beneficial for providing comprehensive hydration to multiple layers of the skin. Consider the following types:

• Small Molecule Hyaluronic Acid: This type has a lower molecular weight, allowing it to penetrate deeper into the skin for hydration at a deeper level.
• Standard or Large Molecule Hyaluronic Acid: These have higher molecular weights and primarily work on the skin's surface, forming a hydrating film that helps reduce water loss and provides a smoothing effect.
• Blends like 4D or 8D Hyaluronic Acid: These products are pre-mixed combinations of different molecular weights, designed to offer hydration to various skin layers and provide a good texture.

Combining a small molecule hyaluronic acid with a standard or large molecule type, or using a blend like 4D or 8D Hyaluronic Acid, would be suitable for your serum to achieve multi-depth hydration.

Other Ingredients

Here is information on the other ingredients you listed:

• Vitamin C (L-ascorbic acid): A potent antioxidant. It requires a low pH (ideally 2.0-4.0, but >= 3.5 for leave-on products per FDA) for effectiveness and is unstable in water. Antioxidants like Vitamin E and Ferulic Acid help stabilize it. Consider Ultra-Fine, Fine, or Standard grades.
• DL-alpha tocopherol (Vitamin E): A key antioxidant that works synergistically with Vitamin C and Ferulic Acid. Use Vitamin E (dl-alpha tocopherol).
• Ferulic acid: A powerful antioxidant that boosts the stability and efficacy of Vitamins C and E. It dissolves in solvents like Ethoxydiglycol or ethanol. Pure-Ferulic Acid™ or the water-dispersible Micromul™ Ferulic Acid are options.
• Ethoxydiglycol: Acts as a solvent and carrier, helping to dissolve ingredients like Ferulic Acid and improving penetration.
• Propylene Glycol and Glycerin: Humectants that attract and retain moisture. Propylene Glycol also acts as a solvent. Use Propylene Glycol and Glycerin (USP/Food Grade).
• Laureth 23: Typically functions as an emulsifier or surfactant. Use Laureth-23.
• Triethanolamine: Used to adjust pH. Use Triethanolamine 99% within recommended rates (max 2.5%).
• Panthenol (vitaminB5): Provides moisturizing and soothing benefits. Water-soluble. Consider Panthenol (Vitamin B5, DL-Panthenol, Powder) or D-Panthenol Care (Pro-Vitamin B5, 100% Liquid).
• Glutathione (L-glutathione reduced): An antioxidant with potential brightening effects. Water-soluble but sensitive to heat and pH. Consider Glutathione (L-Glutathione) (Extrasol) or Glutathione (L-Glutathione Reduced).

Remember to consult reliable formulation resources, such as the forum post linked by the staff member, and follow specific mixing instructions and usage rates for each ingredient to ensure a stable and effective serum.