Abstract
Ultra performance liquid chromatographic method was described for determination of Miconazole Nitrate and Betamthasone Valerate in bulk powder and in topical cream. The chromatographic separation was achieved on Kinetex core-shell C18 column (75x 2.5 mm, 1.8 μm). The separation is achieved applying a simple gradient program. The mobile phase contain a mixture of 0.05% orthophosphoric acid as aqueous solvent and acetonitrile as organic solvent in a gradient program was investigated to separate the drugs from their stressed degradation products. The flow rate was 1.3 ml min-1 and the column temperature was maintained at 40ºC. The detector wavelength was 230 nm. Miconazole Nitrate and Betamthasone Valerate were subjected to stress degradation conditions of hydrolysis (acid and base), oxidation and thermal degradation at 80°C for 1 hour. Stressed samples were analyzed by the developed procedures. The described method shows excellent linearity over a range of 20-300 μgml-1, 1-15 μgml-1 and determination coefficients were 0.9999 and 1 for Miconazole Nitrate and Betamthasone Valerate, respectively. Limits of detection were 0.77 and 0.34 μgml-1 and limits of quantification were 2.3 and 1 μgml-1 for Miconazole Nitrate and Betamthasone Valerate, respectively. Degradation of Miconazole Nitrate was observed in oxidative condition but found to be stable in other stress conditions while Betamthasone Valerate degradation was observed in acidic, alkaline and thermal conditions but found to be stable in oxidative degradation. This method capable of complete chromatographic separation of Miconazole Nitrate and Betamethasone Valerate peaks from their degradation product peaks generated under various stress conditions.
