Selective Hplc Method: Stability Indicating Method

Selective HPLC method , Stability indicating high performance liquid chromatographic method ,simultaneous precise determination of promethazine (PROM) and sodium benzoate (SBENZ), even in the presence of the main oxidative degradation products of PROM , Promethazine (PROM), like other phenothiazines, may become photobiologically active via formation of photolytic products, a number of them being cytotoxic,determination of the comparative protective effect of different antioxidants usually added. Different stability studies were planned to show any interference in the separation of PROM from SBENZ especially in the presence of some common auto-oxidation supressants, such as buylated hydroxy toluene (BHT), buylate hydroxy anisole (BHA) or sodium metabisulfite