Azeco Cosmeceuticals

6.2. How to avoid crystallization Crystallization of azelaic acid is best determined using optical microscopy using polarised light. Crystals of azelaic acid in emulsions or gels are birefringent and are easily detected. To avoid crystallization suitable solvent(s) shall be used that is/are able to keep azelaic acid mono-molecularly in solution. That is applicable for emulsions in both the water or oil phase, but also for aqueous/ hydrophilic gel preparations. Eventually also a solvent can be applied (see the solubility tables reported above), but the amount of azelaic acid that can be solubilized is rather limited. An exception are gels based on phospholipids, more particularly phosphatidylcholine. These are the so-called organogels that exhibit an extreme potential for transdermal transport for pharmaceutical and cosmetic actives (see: Formulation of organogels).

The highest grade of azelaic acid for skin- and haircare

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