Concentrated Arbutin Serum Formulation

To create a concentrated arbutin serum, the primary ingredient should be Alpha Arbutin. It is a highly effective and safe skin brightening agent that works by inhibiting the enzyme responsible for melanin production.

For a concentrated serum, it is recommended to use Alpha Arbutin at a rate of 2%. There are different grades available, including Alpha Arbutin (Switzerland) and Alpha Arbutin from China (Enzymatic Synthesis or Crystal Form), all of which are effective.

Key Considerations for Formulation:

• Solubility: Alpha Arbutin is water-soluble. Add it to the water phase of your formulation.
• Mixing Temperature: Add Alpha Arbutin during the final phase of mixing, ensuring the temperature of the cosmetic base is below 30°C.
• pH Level: The optimal pH range for Alpha Arbutin stability and effectiveness is 3.5-6.5. Avoid formulations with a pH higher than 8, as this can cause Alpha Arbutin to break down into hydroquinone.
• Discoloration Prevention: To help prevent the serum from discoloring, it is highly recommended to include ActiveProtec™ OX at a rate of 0.6% in your formula.

Alternative Ingredient:

Deoxyarbutin (D-Arbutin) is another ingredient known for its high whitening efficiency. However, it is oil-soluble and can cause significant skin irritation in some individuals. If considering Deoxyarbutin, start with a low concentration (e.g., 0.5%) and be cautious, especially on sensitive skin. It requires different mixing conditions (dissolved in oil phase below 60°C) and has a different optimal pH range (5.0-5.8). ActiveProtec™ OX is also recommended for Deoxyarbutin formulas.

Given the user's request for a concentrated serum and the desire for effectiveness with safety, Alpha Arbutin at 2% is the most suitable primary recommendation, following the specified pH and mixing guidelines, and including ActiveProtec™ OX for stability.