AHA 30% Gel Formulation and Cloudiness Issue

Regarding your questions about making a 30% AHA gel for facial peeling:

1. pH Adjustment: You are correct. For a 30% Glycolic Acid peel intended for professional use (like in a clinic), the pH should be adjusted to not lower than 3.0. This is in line with regulatory guidelines for higher concentrations of AHA.

2. Cloudiness with Eye Preserved: The reason your gel became cloudy after adding Eye Preserved is due to an incompatibility issue. Eye Preserved (Polyhexamethylene Biguanide, PHMB) is a cationic ingredient, while Pro Polymer (ACRYLATES/C10-30 ALKYL ACRYLATE CROSSPOLYMER) is an anionic polymer. When cationic and anionic ingredients are mixed, they can interact and cause the polymer to precipitate or destabilize, leading to cloudiness or a loss of viscosity.

   The staff's suggestion to add Eye Preserved before the gel maker is a good attempt to avoid adding a cationic ingredient directly into an already-formed anionic gel structure, which can cause immediate collapse. However, the fundamental incompatibility between the two ingredients means that mixing them in the same formula will likely still cause stability issues or cloudiness over time, regardless of the mixing order.

   To avoid this problem, you would ideally use a preservative that is compatible with anionic polymers like Pro Polymer, or choose a gel maker that is compatible with cationic ingredients if you specifically need to use Eye Preserved.

3. Pro Polymer vs. Xanthan Gum Texture: Both Pro Polymer and Xanthan Gum can be used to create viscous gels. As discussed in the replies, they offer different textures. Pro Polymer tends to give a smoother, less "slimy" feel compared to some types of Xanthan Gum. However, it's important to note that both Pro Polymer and Xanthan Gum are anionic polymers and are incompatible with cationic ingredients like Eye Preserved, which would cause the same cloudiness issue with either gel maker.

In summary, maintaining a pH of 3.0 for a 30% Glycolic Acid peel is correct. The cloudiness is caused by the incompatibility between the cationic preservative (Eye Preserved) and the anionic gel maker (Pro Polymer). Consider using compatible ingredients to achieve a clear and stable gel.