| 摘要 |
FIELD: pharmaceutical industry. SUBSTANCE: cyclomethylaside is high-active diuretic, derivative of 1,4-benzotiadiazine. Wide usage of preparation supposes availability of high-effective, sensitive, selective methods of analysis of given preparation. There are widely known methods of quantitative determination of cyclomethylaside by process of potentiometric titration and by method of ultra-violet spectrophotometry. Proposed method of photocolorimetric and spectrophotometric determination of cyclomethylaside is performed as follows: cyclomethylaside is subjected to acidic hydrolysis, formed product of hydrolysis is injected into reaction of diazotization and subsequent interaction of formed diazonium salt with alcohol solution of 3-α,γ-dicarboxypropylrodanine in alkaline medium with subsequent photometric measurement of obtained colored solution. Optical density of obtained colored solutions is measured by means of photocolorimeter KFK-2 at l-490 ± nm and spectrophotometer SF-46 at 499 nm. Calculation of content of cyclomethylaside in samples is carried out by calibration graphs or by intercept form of equation of straight lines corresponding to rectilinear sections of calibration graphs plotted in advance. Proposed method of quantitative determination makes it possible to find cyclomethylaside with relative error not exceeding + 1.95%. Method is highly efficient and sensitive. Technique of photometric determination of cyclomethylaside developed by inventors may be recommended for practical usage in quality control and chemical laboratories. EFFECT: increased efficiency and sensitivity of method. |
