Substoichiometric determination of iridium using PAN as a reagent

Conditions are established for the substoichiometric determination of iridium employing 1-/2-pyridylyzo/-2-naphthol /PAN/ as a chelating agent. Iridium forms a red coloured complex /12/ with PAN at pH 5 /acetate buffer/, on heating for 60 min in a boiling water bath. The complex was extracted with chloform. Tens of micrograms of iridium were determined with an accuracy of ±0.38%. Effects of diverse metal ions on the determination of iridium were studied and methods for suppression of interferences were developed.