Ingredient pH Compatibility in Low pH Cream Formulas

Hello,

Thank you for your detailed questions and information! We understand that you are focusing on selecting ingredients for maximum effectiveness and stability.

Allow us to confirm your understanding regarding pH based on the information previously provided by our staff:

• Oil-soluble ingredients or ingredients in oil form: Generally, these ingredients do not have a pH value that can be practically measured, as pH is a measure of hydrogen ion concentration in an aqueous solution. Therefore, your understanding that this group of ingredients does not have a pH and can be mixed into formulas with high or low pH is correct.
• Water-soluble ingredients: Most of these ingredients have their own pH and a suitable pH range for stability (stable pH range). This understanding is correct. If a water-soluble ingredient is outside its suitable pH range, it may degrade, lose effectiveness, or undergo physical changes.

Regarding your concern about the 17 moisturizer ingredients you are interested in, many of which do not specify a suitable pH range:

Based on the general principle previously communicated by our staff, for ingredients where the manufacturer has not specifically indicated a suitable pH range, the standard range of pH 3.5-7 can be used as a general guideline for stability.

Therefore, the 17 moisturizer ingredients you listed, most of which do not have a specified pH range (except Natural Moisturizing Amino Acids, which indicates the pH of the ingredient itself is 6-7 but not a stable range), should generally be usable in a cream formula with a pH of 3.5. This is because pH 3.5 falls within the standard range of 3.5-7. However, if you intend to adjust the formula's pH to be below 3.5, it may be necessary to check for more specific data from each ingredient supplier or perform stability testing on your formula.

Regarding whether Hydro-Urea® (Hydroxyethyl Urea) is the same as regular Urea: Hydroxyethyl Urea is a derivative of Urea. It is often developed to improve certain properties, such as reducing tackiness, providing a better skin feel, or increasing stability under certain conditions, but both have similar moisturizing properties.

Finally, formulating a stable cream base at a low pH, especially a rich occlusive cream, can be challenging in terms of maintaining emulsion stability and preventing separation. You may need to consider using emulsifiers and thickeners that are suitable for acidic conditions.

We hope this information is helpful for your formulation process. If you have any further questions, please feel free to ask.

Thank you for your kind words about the MyskinRecipes team. We are very happy to share knowledge and be a part of your product creation journey.