Determination of Ultratrace Amounts of Ruthenium(III) by the Delayed Autocatalytic Reaction Using Citric Acid

摘要

A method for determination of ultratrace amounts (ppq levels) of ruthenium(III) was developed using a copper(II)-phthalocyanine-3,4′,4″,4′′′-tetrasulfonic sodium salt (Cu-PTS) as an indicator in a potassium bromate autocatalytic reaction system. A satisfactory calibration curve of ruthenium(III) ion was obtained by the time measurement in the concentration range of 1 × 10-13 M to 5 × 10-12 M with the relative standard deviation (RSD) of 2.8% (n = 5). The determination limits (3 σ) were 3.30 × 10-14 M (3.34 ppq).