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Published on: August 30, 2018
Spectrophotometric determination of cephalexin in dosage forms with imidazole reagent
A A Alwarthan1, S A Fattah, N M Zahran
1Chemistry Department, College of Science, King Saud University, P.O. Box 2455, Riyadh-11451, Saudi Arabia.
Abstract:
A simple spectrophotometric method is proposed for the determination of cephalexin. The method involves acetylation of cephalexin with acetic anhydride in aqueous solution at pH 11.5 to yield alpha-acetamidocephalexin and subsequent measurement at 335 nm of alpha-acetamidocephalexin mercuric mercaptide. The method characterizes a newly developed, sensitive procedure for the determination of cephalexin in different pharmaceutical preparations. The effect of several reaction conditions were investigated. Beer's law was obeyed over the concentration range 30-340 mug/ml. The results compare favourably with those obtained by the official B.P. 1980 method.
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