Spectrophotometric determination of methyldopa in pharmaceutical formulations
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Abstract
determination in pharmaceutical preparations is described. This method is based on the complexation
reaction of methyldopa with molybdate. Absorbance of the resulting yellow coloured product is measured
at 410 nm. Beer’s Law is obeyed in a concentration range of 50 – 200 μg ml -1 methyldopa with an
excellent correlation coefficient (r = 0.9999). No interference was observed from common excipients in
formulations. The results show a simple, accurate, fast and readily applied method to the determination of
methyldopa in pharmaceutical products. The analytical results obtained for these products by the proposed
method are in agreement with those of the Brazilian Pharmacopoeia procedure at 95% confidence level.
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