Selective spectrophotometric determination of trace amounts of iron with di(2-pyridyl)-NN-di[(8-quinolyl)amino]methane: determination of iron in blood serum

Abstract

Di(2-pyridyl)-NN-di[(8-quinolyl)amino]methane (DPQAM) has been examined to evaluated its usefulness as a sensitive and selective spectrophotometric reagent for iron. A green complex is formed, which is extracted into chloroform at pH 2.9–5.4 in the presence of perchlorate and ascorbic acid (the molar absorptivity, ε= 1.14 × 10⁴l mol^–1 cm^–1 nm). The distribution ratio of this extraction is very favourable, so that iron can be determined in the range 0.25–2.50 p.p.m. (ε= 1.71 × 10⁵l mol^–1 cm^–1). The effect of foreign ions has been studied and the method has been applied to the determination of iron in blood serum with good results.