Catalytic spectrophotometric determination of ruthenium by flow injection method

A sensitive and selective method has been introduced for the determination of ultra trace amounts of Ru(III) based on its catalytic effects on the oxidation of Brilliant green (BG) by sodium bromate. A flow injection method has been used with spectrophotometric detection. The method is based on measuring the decrease in absorbance of BG at λmax=615 nm. The decrease in absorbance of BG is linear with the concentration range of 0.005–0.500 μg ml−1 Ru(III). The limit of detection is 0.002 μg ml−1. The influence of reagent concentration, manifold parameter and potential interference species has been investigated. The method was used for the determination of ruthenium in synthetic samples with satisfactory results.