Sunscreen Cream Formulation with Vitamin C, Phloretin, and Green Tea SPF32 PA++

Creating a stable and effective sunscreen cream with Vitamin C, Phloretin, and Green Tea extract requires careful consideration of ingredient compatibility, especially regarding pH and stability.

Key Ingredients and Considerations:

• Vitamin C: While L-Ascorbic Acid is a potent form, it is highly unstable in water and requires a low pH (2.0-4.0) for stability, which can be challenging to formulate in a cream and may affect other ingredients. A more stable water-soluble derivative like Ascorbyl Glucoside (AA-2G) is often preferred for cream formulations, although it requires a specific pH range (6.5-6.8) for optimal stability.

• Phloretin (Pure-Phloretin™): This antioxidant can enhance the effectiveness of Vitamin C and provides its own free radical protection. It disperses in cream bases but does not dissolve in water or oil.

• Green Tea Extract (Hi-EGCG™): Known for its antioxidant and anti-inflammatory properties, this extract is water-soluble and typically used at a pH between 4.0-6.5. It is sensitive to heat and metal ions.

• Sunscreen Filters: To achieve SPF32 PA++, a combination of UV filters is necessary to provide broad-spectrum protection against both UVA and UVB rays. Filters like BEMT (Tinosorb S), Bisoctrizole (Tinosorb M), and Octocrylene are commonly used for their effectiveness and stability.

• Cream Base (Soft Cream Maker™): A suitable emulsifier system is needed to create the cream texture and ensure the stability of the oil and water phases.

Formulation Challenges:

The primary challenge in combining these ingredients is their differing optimal pH ranges for stability and efficacy. L-Ascorbic Acid requires a significantly lower pH than Ascorbyl Glucoside or Green Tea extract. Formulating with Ascorbyl Glucoside and Green Tea extract together requires finding a compatible pH range, likely between 6.0-6.5, which may not be ideal for either ingredient individually but could be a workable compromise. The stability of the chosen Vitamin C form, Phloretin, and Green Tea extract within the final sunscreen base, especially under UV exposure, must be carefully evaluated.

General Formulation Approach (Conceptual):

A typical approach would involve creating a water phase containing water-soluble ingredients like Ascorbyl Glucoside and Green Tea extract (added during the cool-down phase). An oil phase would contain oil-soluble sunscreen filters and the cream maker, heated to melt the emulsifier. The two phases would be combined and emulsified, followed by cooling and the addition of heat-sensitive ingredients like Phloretin and the pre-dissolved Vitamin C and Green Tea extract, with final pH adjustment.

Please note: Developing a stable and effective sunscreen formulation with a specific SPF and PA rating requires specialized knowledge, precise measurements, and rigorous testing (including in-vivo or in-vitro SPF/PA testing) to ensure both efficacy and stability. The compatibility and stability of all ingredients in the final mixture must be confirmed.