Acta Pharm. 58 (2008) 87-97
Original research paper
A sensitive spectrophotometric method for the
determination of H2-receptor antagonists by means of N-bromosuccinimide
and p-aminophenol
IBRAHIM A. DARWISH, SAMIHA
A. HUSSEIN, ASHRAF M. MAHMOUD and AHMED I. HASSAN
idarwish@ksu.edu.sa
Department of Pharmaceutical Analytical Chemistry,
Faculty of Pharmacy,
Department of Pharmaceutical
Analytical Chemistry, Faculty of Pharmacy,
Accepted December 11, 2007
A simple, accurate and sensitive spectrophotometric method for
determination of H2-receptor antagonists: cimetidine (CIM),
famotidine (FAM), nizatidine (NIZ), and ranitidine hydrochloride (RAN) has been
full developed and validated The method was based on the reaction of these
drugs with NBS and subsequent measurement of the excess N-bromosuccinimide
by its reaction with p-aminophenol to give a violet colored product (lmax at 552 nm). Decrease in the absorption intensity (DA) of the colored product, due to the presence of the drug, was
correlated with its concentration in the sample solution. Different variables
affecting the reaction were carefully studied and optimized. Under optimal
conditions, linear relationships with good correlation coefficients
(0.9988-0.9998) were found between DA values and the corresponding
concentrations of the drugs in a concentration range of 8-30, 6-22, 6-25, and 4-20 mg mL-1 for CIM, FAM, NIZ, and RAN, respectively. Limits of detection were 1.22, 1.01, 1.08, and 0.74 mg mL-1 for CIM, FAM, NIZ, and RAN, respectively. The method was validated
in terms of accuracy, precision, ruggedness, and robustness; the results were
satisfactory. The proposed method was successfully applied to the analysis of the
above mentioned drugs in bulk substance and in pharmaceutical dosage forms;
percent recoveries ranged from 98.5 ± 0.9 to
102.4 ± 0.8% without interference from the
common excipients. The results obtained by the proposed method were comparable
with those obtained by the official methods.
Keywords: H2-receptors antagonists, N-bromosuccinimide,
p-aminophenol, spectrophotometry, pharmaceutical analysis