title: Spectrophotometric reaction rate method for the determination of osmium by its catalytic effect on the oxidation of gallocyanine by bromate.
abstract: A simple kinetic spectrophotometric method was developed for the determination of osmium. The method is based on the catalytic effect of osmium as osmium tetroxide on the oxidation of gallocyanine by bromate at pH 7. The reaction is monitored spectrophotometrically by measuring the decreasing absorbance of gallocyanine at 620 nm by the fixed-time method. A detection limit of 0.01 ng/ml and linear calibration curve from 0.1 to 100 and from 100 to 1200 ng/ml Os(VIII) is reported. The relative standard deviation for 0.0100 microg/ml Os(VIII) is 0.8% (N = 10). The method is free from most interferences. Osmium in synthetic samples is determined by this method, with satisfactory results.
authors.affiliation: College of Chemistry, Isfahan University of Technology, Isfahan, Iran.
authors.forename: A A
authors.initials: AA
authors.lastname: Ensafi
authors.forename: E
authors.initials: E
authors.lastname: Shamss-E-Sollari