Azeco Cosmeceuticals

2.3.

Emulsions based on polymeric emulsifiers.

Polymeric emulsifiers behave in a similar fashion as acrylic acid-based polymers (see § 1.1) and these emulsions are easily broken using a saturated NaCl solution. The test sample is centrifuged using a standard centrifuge @10,000 rpm during eight minutes. The oil/water interface must be sharp. The two phases are separated and the oil phase is dried with anhydrous sodium sulphate. Both the oil phase and the water phase may contain azelaic acid and must be analysed according to the methodology as described in § 1.1.

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There is no general procedure available for the quantitative determination of the assay of azelaic acid in consumer products; a general procedure is also not possible.. Good laboratory practice and creativity of the analytical chemist(s) are prerequisites for the performance of the quantification of azelaic acid in consumer products.

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