Spectrophotometric determination of iron, copper and zinc in sera using 2-(5-nitro-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol

摘要

2-(5-nitro-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol (nitro-PAPS) reacts with iron (II), copper and zinc, but not with iron (III). The iron (II) complex is formed at pH 3.4-9 and has an absorption maximum at 582nm. Copper forms a 1:1 complex at pH2.5-4.5 and a 1:2 complex at pH 8-9. Zinc reacts at pH 8-9. The absorp- tion maxima of copper and zinc complexes are at 565nm.