Ingredient Compatibility Issues: Zinc PCA, Glutathione, L-Carnitine, and Vitamin C
Question
I am formulating a product containing Glutathione (ID 225), Zinc PCA (ID 252), L-Carnitine (ID 157), and Vitamin C (L-ascorbic acid, ID 133). I am encountering difficulties with Glutathione not dissolving in the formula.
Could you please advise on the potential reasons for this solubility issue and the compatibility of these specific ingredients with each other in a single formula, particularly regarding the interaction between Zinc PCA and the other components like L-Carnitine and Vitamin C?
Answer
Based on the staff's testing, the issue with Glutathione not dissolving in your formula seems to stem from incompatibilities between ingredients, although they noted Glutathione itself should be soluble. Specifically, the staff found that:
- Zinc PCA reduces the solubility of L-Carnitine.
- Zinc PCA causes Vitamin C (L-ascorbic acid) to degrade quickly because Vitamin C is incompatible with metal ions.
The staff's recommended solution to address these issues (and implicitly the Glutathione problem, as it was the main change in their suggested revised formula) is to remove Zinc PCA from the formula.
If you wish to use both Zinc PCA and Vitamin C, the staff recommends using them in separate formulas applied at different times (e.g., morning and evening) to avoid interaction.
The staff also mentioned contacting customer service regarding the damaged ingredients.
Relevant product IDs from the discussion are:
- Glutathione: 225
- Zinc PCA: 252
- L-Carnitine: 157
- Vitamin C: 133
Related Products Mentioned
Vitamin C (L-ascorbic acid) (Ultra-Fine)
L-Carnitine (Carnitine)
Glutathione (L-Glutathione) (Extrasol)
