A new spectrophotometric method has been developed for determining diphenhydramine. HC1, based on solvent extraction into chloroform of the complex formed with bromocresol green. The complex solution in chloroform showed maximum absorption at 415 nm and obeyed Beer's law over the concentration range of 3.0-12.0 microgram/ml. The molar absorptivity of the complex was 2.02 x 10(4). Complex formation and extraction was complete and quantitative over the pH range from 2 to 5. The ratio of diphenhydramine to bromocresol green was 1:1. Excipients, coloring matter, flavoring agents, and other substances likely to be present in diphenhydramine preparations do not interfere in the determination. Direct determinations in tablet, capsule, sirup, and lotion preparations were carried out satisfactorily, and the average recovery was 100 +/- 1.0%.
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Inflammopharmacology
January 2010
Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
We clarified the roles of histamine H(1)-, H(2)-, H(3)-receptors and oxyradicals in the exacerbation of acid-induced gastric haemorrhage and stomach ulcer in endotoxaemic rats by measuring changes in gastric mucosal glutathione concentrations, lipid peroxide generation and histamine levels as well as in luminal electrolytes and haemoglobin contents. Stomach ulcers were evaluated by morphological and histological examination. Rats were deprived of food for 24 h, and challenged intravenously with lipopolysaccharide (LPS, 3 mg/kg) at 0, 12, 18 and 24 h after withdrawal of food.
View Article and Find Full Text PDFJ Assoc Off Anal Chem
July 1977
A new spectrophotometric method has been developed for determining diphenhydramine. HC1, based on solvent extraction into chloroform of the complex formed with bromocresol green. The complex solution in chloroform showed maximum absorption at 415 nm and obeyed Beer's law over the concentration range of 3.
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