Azeco Cosmeceuticals

Question Customer How to dissolve azelaic acid?

Answer

The limited solubility of azelaic acid in aqueous conditions requires some creativity. There are several methods to incorporate azelaic acid in a final formulation using a premix. The most straight forward approach is to dissolve azelaic acid in ethanol or isopropanol. For many preparations these alcohols are not the most preferred substances. In that case a suitable diol will do the job. We have tested propanediol (Zemea®; Dupont), as well as 1,3-butylene glycol and pentylene glycol. Pentylene offers the advantage that it also gives a massive microbiological protection. Pentylene glycol is available from petrochemical origin (Symrise, Minasolve), but also from vegetable origin, obtained by hydroge- nation of furfuraldehyde (from wood processing; Minacare Pentiol Green/Minasolve). Also glycerin and glycerin/water mixtures are suitable solvent systems; the maximum concentration water in this solvent mixture are not properly defined and not reported in the literature. A second, but far more expensive option is to dissolve azelaic acid is a mixture of phosphatidylcholine & isopropyl palmitate. In this case a premix is made of azelaic acid in an aqueous glycerin solution. This procedure is only recommended when dissolution in gly- cols of glycerin/water mixtures fails.

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