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Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry | ||
Journal of the Iranian Chemical Research | ||
مقاله 8، دوره 2، شماره 4، اسفند 2009، صفحه 293-297 اصل مقاله (42.86 K) | ||
نویسنده | ||
Ateesa Yazdanipour* | ||
Department of Chemistry, Faculty of Sciences, Islamic Azad University, Arak Branch, Arak, Iran | ||
چکیده | ||
The acid-base equilibrium of lorazepam was studied by means of potentiometry and multiwavelengths spectrophotometry. The stoichiometric equilibrium constants were determined at 25 °C and constant ionic strength 0.1 mol L-1 (NaCl). The acidity constants pK1=1.58±0.05 and pK2=11.67±0.07 were found by potentiometry, and pK1=1.54±0.02 and pK2=11.61±0.03 by multi-wavelengths spectrophotometry. Potentiometric determination of equilibrium constants was performed by application of the formation function method. Data analysis program applied for multi-wavelengths spectrophotometric determination of acidity constants. | ||
کلیدواژهها | ||
Lorazepam؛ Acidity constants؛ Potentiometry؛ Spectrophotometry | ||
مراجع | ||
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