Analyses of Drugs and Chemicals by Infrared Absorption Spectroscopy. XV. : Determination of Sulfonamides by Use of Dimethylformamide as Solvent

Abstract

A simple infrared spectrophotometric method is offered for determination of sulfathiazole and sulfamerazine in a mixture, and sulfathiazole and sulfadiazine in a mixture, by the use of dimethylformamide as a solvent. The infrared spectra of the two polymorphs of sulfathiazole are clearly different in the solid phase, but quite identical in dimethylformamide solution. Therefore, the solution method is available for quantitative analyses, and this method gave good results in both mixed samples of sulfathiazole (919 cm^-1) and sulfamerazine (958 cm^-1), and of sulfathiazole (729 cm^-1) and sulfadiazine (929 cm^-1).