Abstract
With the use of the apparatus described in Report III of this series, experiments on electrophoresis have been carried out in three buffer solutions of Clark-Lubs, Sorensen, and Kolthoff. The maximum mutual differences of migration distance of sulfamines in any of these buffer solutions were shown at pH 7.0, and the differences of migration distance of anilides were great at pH 2.0. The separation and identification of those with these pH values were possible by carrying out the test at 400 V, 1mA/cm, and at 15°C for 60 minutes. The detection of migration zones was accomplished by spraying a solution composed of 3 g p-dimethylaminobenzaldehyde and 7 g conc H2SO4 in 100 ml water on the air-dried paper used for electrophoresis. This treatment caused the sulfamines to give an orange color up to 0.2γ and the anilides to give a yellow color with the limit of detection up to 0.25γ.
