Non Aqueous Titration for the Determination of Azelaic Acid: Introduction and Method Validation

Alpha-hydroxylic acids are widely used in the treatment and control of skin disorders. Azelaic acid is a naturally occuring Alpha-hydroxy acid that can be formed endogenously from long-chain dicardoxylic acids, metabolism of oleic acid or omega oxidation of mono carboxylic acids. It shows bacteriostatic and bactericidal activities against aerobic and anaerobic micro-organisms present on acne-bearing skins. The beneficial effects of azelaic acid have been lead to different pharmaceutical formulations such as creams, gels, etc. HPLC and GC techniques are mostly used for the determination of Azelaic acid in plasma. These techniques are very accurate but, they are expensive and time consuming due to the lack of chromophore and consequently the necessity of pre-column sample preparation. For the determination of Azelaic acid in pharmaceutical dosage forms, a simple method with suitable accuracy and precision is needed. In this research, non aqueous titration was used for the determination of azelaic acid. For this purpose, azelaic acid was titrated by sodium methoxide in the presence of thymol blue. The results of method validation by considering various parameters showed the accuracy of the suggested method in the determination of azelaic acid in pharmaceutical formulations