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  • Author or Editor: S. Mehta x
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A novel, simple, robust, and rapid reversed-phased high-performance liquid chromatographic method has been developed for the separation and quantitative determination of the related substances of ezetimibe and simvastatin in combined dosage forms. Successful separation of the drug from the process-related impurities and degradation products formed under stress conditions was achieved on Inertsil ODS-3V (150 × 4.6 mm, 5.0 μm) column. The gradient liquid chromatography (LC) method employs solution A and solution B as mobile phase. The solution A contains 0.1% orthophosphoric acid solution in water, and solution B contains 0.1% orthophosphoric acid solution in acetonitrile. Flow rate was monitored at 2.0 mL/min, and the ultraviolet (UV) detection, at 238 nm. In forced degradation studies, the effect of acid, base, oxidation, UV light, and temperature was investigated, showing that good resolution between the peaks corresponds to process-related impurities and degradation products from both analyte. The performance of the method was validated according to the present International Conference on Harmonization (ICH) guidelines for specificity, limit of detection, limit of quantification, linearity, accuracy, precision, ruggedness, and robustness. To the best of our knowledge, a rapid LC method, which separates all the impurities of ezetimibe and simvastatin in combined dosage forms, disclosed in this investigation was not published elsewhere.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Alrakabi, G. Singh, A. Bhalla, S. Kumar, S. Kumar, A. Srivastava, B. Rai, N. Singh, J. Shahi, and D. Mehta

Abstract  

The elemental concentration of uranium in the samples collected from the ground water and the canal water in the Bathinda district of Punjab state, India, have been investigated using X-ray fluorescence technique. The residues obtained after drying the water samples were analysed using the energy dispersive X-ray fluorescence spectrometer consisting of Mo-anode X-ray tube equipped with selective absorbers as an excitation source and an Si(Li) detector. The uranium concentration values in significant fraction of the shallow ground water samples from the hand pumps is found to be above the permissible level of 15 ppb recommended by World Health Organisation for the drinking water, and its values in the canal water samples are below 5 ppb. To investigate the flyash from the coal-fired thermal power plants as a possible source of ground water contamination, the water samples collected from the surroundings of the power plants and the flyash samples were also analyzed. The results rule out flyash as a source of uranium contamination. Agrochemical processes occurring in the calcareous soils in the region are the favoured potential source of uranium contamination of the ground water.

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