Azeco Cosmeceuticals

Sommario Solubility 1. Question: How to improve the solubility of Azelaic acid?

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2. Question: How to dissolve Azelaic acid?

3. Question: Should we consider 10-15 % Azelaic acid in Propanediol?

4. Question: Is the solubilty of Azelaic acid in propanediol 1,3 similar to that of propylene glycol?

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5. Question: We have tried another source of Azelaic acid (not Azepur99®) and experienced some problems with crystallization for an skin prone to acne application.

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6. Question: Is Azepur99® is soluble in glycerin, 1.3-Butylene Glycol or Propanediol?

7. Question: When Azepur99® is dissolved in glycols or glycerin, what rheology modifier should be used to make a fully transparent gel of this solution? 8. Question: Except Hydroxypropylcellulose (HPC), and Sodium Polyacryloyldimethyl Taurate, can other rheology modifier be used?

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9. Question: What can be done to make the Azelaic accid penetrate even deeper into the skin?

Formulations 10. Question: We have developed an emulsion with 10% Azelaic acid, to increase the solubility of Azelaic acid, we need to increase pH of the aqueous phase before emulsification and before adding the Azelaic acid. Should the pH raised to 7 or more? To have good stability and to avoid the crystallization of Azelaic acid, what should be the optimum pH of the emulsion?

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11. Question: How to create a base formulation and add per skin type a different active

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ingredient?

12. Question: In the formulation we experienced some colouring due to oxidation. Could you recommend addition of an anti-oxidant in the formulation? 13. Question: Which combination can you recommend for Azelaic acid together with other ingredients to reinforce the whitening action: niacinamide? 14. Question: Question on the activity in the free acid or neutralized state: I’ve been pretty careful not to neutralize by post adding it to a PH of 5.5. Are there any differences in the free or salt state? 15. Question: How to formulate a peeling with 10-15 % Azelaic acid? The final product should be a liquid or a gel. 12 18. Question: We are developing a new formulation. We encountered an issue of solubility in water. Did an suggestion to use ethoxydiglycol. The condition improve a lot after the application of ethoxydiglycol. 13 19. Question: In a formulation we add Azelaic acid directly in the oil phase. The pH is between 4 and 5, is this the correct pH or should it be higher? 13 20. Question: Can a natural hydrocolloid (INCI: Carrageenan and Algin, pH 8-11), carbomer be used? 13 mulation? 10 10 11 12 16. Question: Can you recommend some formulation concepts?

Mussenberg 1 • 6049 GZ Herten • The Netherlands

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