Analytical Sciences


Abstract − Analytical Sciences, 21(12), 1561 (2005).

A New Objective Method to Compare Different Color Reactions for the Detection of Cyclic Ureides
Manuela MEUSEL, Maxim FRIZLER, and Michael GÜTSCHOW
Pharmaceutical Institute Poppelsdorf, University of Bonn, Kreuzbergweg 26, D-53115 Bonn, Germany
Modifications of the Zwikker- and Parri color detection tests were examined and compared according to their ability to distinguish between nine different barbituric acids and hydantoins. These tests comprised the formation of complexes with cobalt(II) and copper(II) salts and organic amines. Using the color palette introduced herein, the evaluation of the tests could be reduced to a simple yes/no decision on the basis of only seven defined colors. Suitable components for the color tests could be selected from the thirty six modifications.