Information Regarding Stabilized Vitamin C (Natural-C Glycol™) Serum Formulation

Thank you for your questions regarding the Stabilized Vitamin C (Natural-C Glycol™) Serum and formulation possibilities. Based on the product information and general formulation principles, here are the answers to your questions:

1. Can other ingredients be added, such as Alpha Arbutin, Niacinamide, Tranexamic Acid, Repair Activator™, or others?
   Adding other ingredients to Stabilized Vitamin C (Natural-C Glycol™) Serum is generally not recommended. The product is formulated as a stable, ready-to-use base with a specific composition designed to maintain the stability and effectiveness of 15% L-Ascorbic Acid in a glycol base. Adding other ingredients can disrupt this stability.

2. How should one determine if adding something is suitable (e.g., based on pH)?
   Yes, pH is a crucial factor, but not the only one. The Stabilized Vitamin C (Natural-C Glycol™) Serum has a very low pH (2-3) to help stabilize the L-Ascorbic Acid. Many common active ingredients like Alpha Arbutin (optimal pH 3.5-6.5), Niacinamide (optimal pH 3-8, best 4-7), and Tranexamic Acid (optimal pH 3-8) require a higher pH range to be stable and effective. Mixing them into a base with a pH of 2-3 would likely cause them to degrade or lose efficacy. Furthermore, the serum is primarily glycol-based with minimal or no water, meaning powder ingredients that require water to dissolve (like Alpha Arbutin, Niacinamide, Tranexamic Acid) would not dissolve properly and could destabilize the formula. Liquid ingredients containing water might mix but could still affect the overall stability due to the pH difference and potential interactions. Repair Activator™ also has a pH range (4-5.5) that is higher than the serum's pH.

3. If other ingredients are added, will the concentration of Stabilized Vitamin C (Glycol) decrease?
   Yes, if you add any other ingredient to the Stabilized Vitamin C (Natural-C Glycol™) Serum, the total volume or weight of the mixture will increase, while the amount of Stabilized Vitamin C (which contains 15% L-Ascorbic Acid) remains the same. This will result in a lower overall concentration of Stabilized Vitamin C (and thus L-Ascorbic Acid) in the final mixture.

4. If I want to increase the concentration of Stabilized Vitamin C (Glycol) to 20%, can I do that? (If so, how?)
   The Stabilized Vitamin C (Natural-C Glycol™) Serum contains 15% L-Ascorbic Acid dissolved in a glycol base. Achieving this concentration in glycols is challenging, as glycols typically can only dissolve L-Ascorbic Acid up to about 5%. The manufacturer uses a special process or technology to achieve the 15% concentration and stability. Simply adding more L-Ascorbic Acid powder or another form of Vitamin C to this serum is unlikely to work. The additional Vitamin C would likely not dissolve and could destabilize the existing solution. Increasing the concentration to 20% would require specialized formulation knowledge and technology, which is not feasible for standard DIY mixing.

5. I noticed that Stabilized Vitamin C (Glycol) is a mixture of Ethoxydiglycol, Butylene Glycol, L-Ascorbic Acid, and Phenoxyethanol (0.7%). Can I mix these myself? What ratio or percentage should I use to get the product sold?
   While the INCI names list the components (Butylene Glycol, L-Ascorbic Acid, Ethoxydiglycol, Phenoxyethanol), simply mixing these raw materials at home will not replicate the Stabilized Vitamin C (Natural-C Glycol™) Serum. As mentioned regarding the concentration, achieving 15% L-Ascorbic Acid stability in a glycol base requires specific manufacturing technology beyond simple mixing. The ratios and process are proprietary to the manufacturer. Attempting to mix these yourself without the necessary technology will likely result in an unstable product where the L-Ascorbic Acid does not fully dissolve and degrades quickly.

In summary, the Stabilized Vitamin C (Natural-C Glycol™) Serum is designed as a finished product base for stability. Modifying it by adding other active ingredients or attempting to replicate it from raw materials is not recommended due to stability issues, pH incompatibility, solubility challenges, and the need for specialized manufacturing processes.