Notes on the estimation of the members of the sulphanilamide group, with special reference to sulphathiazole

Abstract

Osterheld''s unexpected difficulties in the estimation of 2-p-aminobenzene-sulfonamidothiazole (i.e., sulfathiazole), especially in urine, have been accounted for and overcome. Details of the method adopted by the writers are given. The color-production[long dash]concentration curves on an absorp-tiometer showed that > 1 standard is essential if comparison is to be made with a colorimeter. Many expts. were made using a great variety of coupling agents, in the hope of finding one which gave an azo dye of sufficient color intensity for use in a micromethod. No coupler was found to compare with N-(l-naphthl)-ethylenediamine dihydro-chloride in this respect.