Simple Spectrophotometric Methods for the Determination of Sulfamethaxazole in Pharmaceuticals Using Folinciocalteau and Orcinol as Reagents

• Published in: E-journal of chemistry 2009, Vol.6 (2), p.357-360
• Main Authors: Raja, G. Vijaya, Sekaran, C. Bala, Teja, D. Winnie, Madhuri, B., Jayasree, B.
• Format: Article
• Language: English
• ISSN: 2090-9063; 0973-4945; 2090-9071; 2090-9810
• DOI: 10.1155/2009/457130

Two simple, sensitive and reproducible spectrophotometric methods (Method A and Method B) were developed for the determination of sulfamethaxazole in bulk and in dosage forms. Method A is based reduction of phosphomolybdic acid present in Folin Ciocalteau reagent by the drug sulfamethaxazole in the presence of sodium carbonate to form a blue colored chromogen having maximum absorption at 760 nm. Method B is based on the diazotization of the drug by sodium nitrite in acidic medium at 5 ° C followed by coupling with orcinol to form yellow colored species (λ max 390 nm). Beer’s law is obeyed in the range of 5‐25 μg/mL for method A and 2‐10 μg/mL for method B. Results of analysis were validated statistically and by recovery studies. These methods are successfully employed for the determination of sulfamethaxazole in various pharmaceutical preparations and biological fluids.