Flow-injection photometric determination of nanogram levels of iron based on the catalysis of oxidative coupling of N-phenyl-p-phenylenediamine with m-phenylenediamine in a micellar medium.
A highly sensitive photometric flow-injection method is described for the determination of iron(II, III) based on the catalytic action on the oxidative coupling of N-phenyl-p-phenylenediamine with m-phenylenediamine in the presence of hydrogen peroxide. The sensitivity of the method was enhanced by the addition of Tween 80 as a surfactant. The dynamic range was 0.5-30 ng/ml of iron(II, III) with the relative standard deviations below 3% at a sampling rate of 30 h(-1). The proposed method was subject to few interferences from coexisting metal ions and was successfully applied to the determination of iron in natural water samples.
Nakano
S
S
Chemical Institute, Faculty of Education, Tottori University, Koyama-cho, Tottori 680, Japan.
Tsujii
K
K
Kawashima
T
T