Adding Cyclomethicone to Reduce Stickiness in Serum

Improving a Pre-Mixed Serum to Reduce Stickiness

I understand you want to fix the stickiness of your already mixed serum without making a new batch. The stickiness you're experiencing is very likely due to the Hyaluronic Acid (Standard Molecule) at 0.5%, which might be a bit high for your desired feel.

Regarding your questions, here are the answers:

1. Can Cyclomethicone be added to fix the problem?

   • Adding Cyclomethicone (such as Cyclopentasiloxane) to a pre-mixed serum is theoretically possible to help reduce stickiness and add a smooth feel, as Cyclomethicone is a lightweight, fast-evaporating silicone.
   • However, adding ingredients to a finished formula is more complex than formulating from scratch. Since your original formula is a water-based serum, adding Cyclomethicone, which is soluble in silicones/oils, could lead to product separation if a suitable emulsifier is not present in the correct amount.

2. If it can be added, what percentage is suitable, and will adding it reduce effectiveness?

   • Suitable Percentage: There is no fixed percentage for adding Cyclomethicone to a pre-mixed product. The optimal amount depends on the remaining volume of your serum and the level of stickiness you want to reduce. Experimenting with a small portion of your serum first is the best approach (e.g., start with 1-5% of the remaining serum volume and gradually increase if needed). However, keep in mind that an emulsifier might be necessary, which makes adjustment difficult in a finished product.
   • Reduced Effectiveness: Yes, the effectiveness of the original active ingredients will be reduced. When you add Cyclomethicone ( or any other ingredient) to your existing serum, the total volume of the product increases while the total amount of the original active ingredients (like Vitamin B3, Panthenol, Glucosamine, Matrixyl 3000, Argireline, both types of Hyaluronic Acid) remains the same. This means the concentration of active ingredients per volume of serum will decrease. Therefore, with each application of the modified serum, your skin will receive a lower amount of these active ingredients compared to the original formula.

Additional Suggestions:

• Since adjusting a finished formula is challenging and can affect the stability and efficacy of the original product.
• You might consider using the current sticky serum as a Night Cream, as previously suggested, where the stickiness might be less of an issue than for daytime use.
• For future formulations, if you desire a lighter, faster-absorbing texture, you should reduce the amount of Hyaluronic Acid (Standard Molecule) and potentially include Cyclomethicone or other lightweight feel modifiers from the initial formulation stage.

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