Serum Formulation: Texture, Stickiness, and Stability with High Actives

Hello,

Based on your proposed serum formula and the previous feedback, here's an analysis and recommendations:

1. Serum Texture:

• Your initial formula with 35-36% actives, plus other ingredients like silicones, SiliSolve Plus, etc., is likely to result in a very thick texture, potentially too thick and difficult to spread or absorb quickly. While you want a thick texture, achieving thick, smooth, fast-absorbing, and non-greasy simultaneously is challenging, especially with a high total percentage of ingredients. The subsequent formula adding Transamine, DMAE, Safe B3, and GlucoBright, while reducing water, would likely be even stickier, as confirmed by the staff regarding DMAE.

2. Ingredients to Reconsider from Section 1 (Initial Formula):

• Vitamin A (Retinyl Palmitate) and Vitamin E (Tocopheryl Acetate): These are oil-soluble. Your formula appears to be primarily water and silicones, with SiliSolve Plus designed to help combine water, oil, and silicones. However, incorporating significant amounts of oil-soluble vitamins like A and the very viscous E requires a properly formulated emulsion system with a defined oil phase, which adds complexity. Without a clear oil phase, they may not be effectively incorporated or stable. Vitamin E's high viscosity also contributes to a heavy feel.

3. Stability:

• Stability is a significant concern when mixing ingredients with different solubilities (water-soluble actives, oil-soluble vitamins, silicones) without a robust and compatible emulsification system. While SiliSolve Plus helps, the high concentration of various ingredients increases the risk of instability (separation, changes in texture or appearance) over time. A simpler formula with water-soluble actives (like B3, HA, GlucoBright, Transamine, DMAE) is generally more stable in a water/silicone base with a suitable emulsifier/dispersant and preservative.
• As noted by staff, SiliSolve Plus requires mechanical blending, not just manual stirring, for proper emulsification.

Regarding the Subsequent Formula and Stickiness:

• You asked about stickiness with the formula containing Transamine (3%), DMAE (3%), Safe B3 (5%), GlucoBright (4%), and Hyaluronic Preserve Free base, with reduced water.
• As the staff confirmed, DMAE is the primary ingredient among those listed that contributes significantly to stickiness, even at 3%. The total percentage of these added actives (3+3+5+4 = 15%) plus the HA base and other ingredients from your initial list (silicones, SiliSolve Plus, etc.) would result in a very high total concentration, leading to a sticky texture, especially for oily to normal skin types.

Recommendations to Achieve Desired Texture (Thick, Smooth, Fast-Absorbing, Less Sticky):

1. Reduce Total Active Concentration: The combined percentage of actives (35-36% initially, plus more later) is very high for a serum aiming for fast absorption and a non-greasy feel. Lowering the total percentage of actives will significantly improve the texture.
2. Reduce or Remove DMAE: Since DMAE is identified as a key contributor to stickiness, reducing its percentage or removing it will help achieve a less sticky feel, particularly important for oily and normal skin.
3. Reconsider Oil-Soluble Vitamins (A & E): If a non-greasy, water/silicone-based serum is the goal, it's best to avoid oil-soluble vitamins unless you formulate a proper emulsion with a suitable oil phase and emulsifier, which is a different type of product.
4. Use a Gel Maker: If you want a thicker texture without relying solely on high concentrations of actives that might cause stickiness, consider incorporating a suitable water-based Gel Maker (like Pro Polymer) into the water phase. This allows you to control viscosity independently of the active concentrations.
5. Balance Ingredients for Skin Type: For oily and normal skin, lower concentrations of potentially sticky ingredients (like DMAE and high percentages of humectants/actives) are generally preferred for a lighter, faster-absorbing feel. Dry skin might tolerate slightly higher concentrations of moisturizing actives, but excessive stickiness is usually undesirable for any skin type.

Regarding the Smell:

• As previously noted, the specific actives you mentioned adding (Transamine, DMAE, Safe B3, GlucoBright) do not have strong odors and are unlikely to significantly change the overall smell of the serum.

In summary, to get a less sticky, faster-absorbing serum while still having a pleasant texture, you need to reduce the total concentration of ingredients, especially those known to cause stickiness like DMAE. Consider using a Gel Maker for viscosity control and carefully select actives based on their solubility and impact on texture.