Determination of ultratrace amounts of ruthenium by differential pulse voltammetry using factorial design for optimization

A simple and sensitive electrochemical technique for the convenient determi nation of trace amounts of ruthenium was developed, based on the catalytic current of a Ru(III)-bromate system on the surface of a hanging mercury ele ctrode at about -0.2 V versus Ag/AgCl reference electrode. The influence of reagent and instrumental variables was completely studied by factorial des ign analysis. Optimum analytical conditions for the determination of ruthen ium were established. Ruthenium(III) can be determined in the range 0.005-0 .350 mu g/ml with a limit of detection of 0.003 mu g/ml. The influence of p otential interfering substances on the determination of ruthenium was studi ed. The method was evaluated by analyzing synthetic samples. (C) 1999 Acade mic Press.