کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2509740 1117685 2009 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A new spectrophotometric method for the determination of methyldopa
موضوعات مرتبط
علوم پزشکی و سلامت داروسازی، سم شناسی و علوم دارویی علوم دارویی
پیش نمایش صفحه اول مقاله
A new spectrophotometric method for the determination of methyldopa
چکیده انگلیسی

A new, simple and low cost spectrophotometric method for the determination of methyldopa in pharmaceutical preparations was developed. The method was based on the coupling of methyldopa with 2,6-dichloroquinone-4-chlorimide (DCQ). The absorbance maximum (λmax) of the resulted colored product was at 400 nm. Different buffers were used to determine the optimal pH for the reaction. About 1% w/v acetate buffer with pH 8.0 gave the optimal pH required for the reaction. Of the different solvents tried, water and ethanol were found to be the most suitable solvents. Beer’s law was obeyed in concentration range of 4–20 μg/ml methyldopa. The correlation coefficient was found to be (r = 0.9975). The limit of detection and limit of quantification were 1.1 μg/ml and 3.21 μg/ml, respectively. The reaction ratio between methyldopa and DCQ was studied and found to be 1:3. The work included the study of the possible interference of hydrochlorothiazide found in combination with methyldopa tablets. The method was validated and results obtained for the assay of two different brands of methyldopa tablets were compared with the BP method (colorimetric). The repeatability and reproducibility of the developed method were evaluated and the obtained results quoted. The derivative formed as a result of the reaction of methyldopa with DCQ was isolated and its possible mechanistic pathway was suggested.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Saudi Pharmaceutical Journal - Volume 17, Issue 4, October 2009, Pages 289–293
نویسندگان
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