title: Determination of trace osmium by supramolecular catalytic kinetic spectrofluorimetry of beta-CD-osmium-KBrO(3)-o-vanillin furfuralhydrazone.
abstract: A supramolecular catalytic kinetic spectrofluorimetric method was developed for the determination of osmium(IV) and the possible mechanism of catalytic reaction was discussed. The method is based on the fluorescence enhancing reaction of o-vanillin furfuralhydrazone (OVFH) with potassium bromate, which was catalysed by osmium(IV) in water medium. Beta-cyclodextrin (beta-CD) obviously sensibilized the determination at pH 6.10 and 55 degrees C. Under optimum conditions, beta-CD-osmium(IV)-KBrO(3)-OVFH supramolecular kinetic catalytic reaction system had excitation and emission maxima at 337 and 490nm, respectively. The linear range of this method was 0-120ngml(-1) with a R.S.D. of 1.1%, and the detection limit was 0.38ngml(-1). The effect of interferences was studied. Distillation was used to separate osmium from interfering elements in the samples. The proposed method was applied successfully to determine osmium(IV) in synthetic mixture and mineral samples, the results were well consistent with the reference standard values.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Tang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang