Gel Formulation for Acne Dark Spots: pH, Ingredient Solubility, and Texture

Question

I have a few questions about formulating a gel for acne dark spots: What is the stable pH range for Apple Stem Cell Extract? Can I use the following gel formula at pH 4 to reduce acne dark spots? Please also advise on potential texture issues at this pH: Mandelic Acid 5% Salicylic Acid EZ™ (water-soluble type) 5% Aloe Vera Extract 3% Polymer™ (Gel Maker) 1% Mild Preserved Eco™ 1% Water 85% Can Ethoxydiglycol dissolve powders that typically require oil for dissolution? For example, dissolving such a powder in Ethoxydiglycol instead of oil. If I have a liquid ingredient that is soluble in oil, can I dissolve it directly in a Cream Maker?

MySkinRecipes Expert · Accepted Answer

Apple Stem Cell pH Stability

Apple Stem Cell Extract (AppleCell™ Powder) is stable within a pH range of 3.5 to 6.5.

Gel Formula for Acne Dark Spots at pH 4

The gel formula you provided, containing Mandelic Acid, Salicylic Acid EZ™, Aloe Vera Extract, Pro Polymer™, Mild Preserved Eco™, and Water, can be formulated at pH 4.

Ingredient Compatibility: Mandelic Acid, Salicylic Acid EZ™, Aloe Vera Extract, and Mild Preserved Eco™ are generally stable and effective at pH 4 or within a range that includes pH 4.
Gel Texture: Pro Polymer™ can be used in formulas with electrolytes (like acids), but high concentrations of electrolytes can soften the gel. You might need to use a higher percentage of Pro Polymer™ than usual (e.g., 2-3% instead of 1%) to achieve the desired gel consistency at this pH, as Mandelic Acid can also affect the gel structure.
Mixing Order: Ensure Salicylic Acid EZ™ is fully dissolved in the water phase before adding the gel maker (Pro Polymer™) to maintain stability and prevent precipitation.

Ethoxydiglycol as a Solvent for Oil-Soluble Powders

Ethoxydiglycol is a solvent and carrier that is soluble in water, glycols, ethanol, and some natural oils. While it can dissolve many substances, it is not a universal solvent for all oil-soluble powders. Whether it can dissolve a specific oil-soluble powder depends on the chemical nature of that powder. It cannot be assumed that Ethoxydiglycol can replace oil for dissolving any oil-soluble powder unless that specific powder is known to be soluble in Ethoxydiglycol as well as oil.

Dissolving Oil-Soluble Liquid Ingredients in Cream Makers

Ingredients that are already in liquid form and soluble in oil do not need to be "dissolved" in the traditional sense. When formulating an emulsion (like a cream), you would typically mix the oil-soluble liquid ingredient with the other oil-based ingredients in your formula. This oil phase is then combined with the water phase in the presence of an emulsifier (cream maker) to create the final cream texture. So, yes, you would incorporate the oil-soluble liquid into the oil phase and mix it with the cream maker as part of the emulsification process.