Serum Formulation Review

Your proposed serum formulation for hydration and brightening appears to be well-designed and includes a good combination of active ingredients targeting these concerns.

Ingredient Compatibility

Based on the ingredients listed, most are water-soluble or dispersible and should be compatible with each other in a serum base. The formulation includes several effective humectants and moisturizing agents such as Glycerin, Snail Secretion, Double Hyaluron Liquid, Fucus Film, MOIST24, and Rice Vitamin, which will contribute to skin hydration.

For brightening, you have included Safe-B3 (Niacinamide), n-acetyl glucosamine (GlucoBright), and Lemon Peel Bioferment. Niacinamide and n-acetyl glucosamine are known to work synergistically for improving skin tone and reducing hyperpigmentation. Lemon Peel Bioferment also acts as a tyrosinase inhibitor, further aiding in brightening.

Dimethyl Isosorbide (DMI) is a suitable penetration enhancer for many of the water-soluble active ingredients in your formula, which should help improve their efficacy.

Pro Polymer is included as a gel maker to provide the desired serum texture. Mild Preserved Eco is a broad-spectrum preservative that should help ensure the stability and safety of the formulation.

Recommendations and Considerations

1. Mixing Procedure: Ensure that the Pro Polymer is fully hydrated in the water phase before adding ingredients that might affect its viscosity. Add heat-sensitive ingredients like Lemon Peel Bioferment in the final cooling phase (below 40°C).
2. pH Adjustment: The optimal pH range for the key active ingredients like Niacinamide, Acetyl Glucosamine, Lemon Peel Bioferment, and Rice Vitamin is generally between 4 and 7. You should check the final pH of your formulation and adjust it to be within this range for optimal stability and effectiveness.
3. DMI Odor: Dimethyl Isosorbide can have a slight ether-like odor. If this is noticeable in the final product, you might consider adding a small amount of fragrance or an odor-neutralizing ingredient.
4. Stability Testing: It is always recommended to perform stability testing on your final formulation to ensure it remains stable and effective over time under various storage conditions.

Overall, the formula seems viable and contains a promising blend of ingredients for achieving both hydration and brightening benefits. With careful preparation and pH adjustment, this serum should be effective.