A Validated, Specific Stability-indicating Rp- Lc Method for Citicoline and Its Related Substances in Oral Drops

A validated, specific, stability indicating reversed-phase liquid chromatographic method has been developed for quantitative analysis of citicoline and its related substances in oral drops formulation. Forced degradation studies were performed using acidic, basic and oxidizing conditions, and thermal and photolytic stress, to show the stability indicating power of the method. The method was optimized by analysis of the samples generated during the forced degradation studies and sample solutions spiked with the impurities. Good resolution between the analyte peak and peaks corresponding to process related impurities and degradation products was achieved on a Whatman Partisil SAX C 18 (250X4.6mm, 10µm) column with a mobile phase constituted of phosphate buffer and acetonitrile (40:60 % v/v) and further comprises of 1gm of 1-hexane sulphonic acid sodium salt. The pH of the mobile phase was adjusted to 3.4 with ortho phosphoric acid. Detection was performed at 280 nm. Citicoline sodium was subjected to stress conditions of hydrolysis (acid, base), oxidation, photolysis and thermal degradations. The method was validated in accordance with ICH guidelines and the validation data showed that the assay is sensitive, specific and reproducible for the determination of citicoline in the presence of related substances and degradation products.