Quantification of Noble Metals in Biological and Environmental Samples

Quantification of Noble Metals in Biological and Environmental Samples 

Department of Analytical Chemistry, Warsaw University of Technology, Warsaw, Poland e-mail mbal ch.pw.edu.pl 

This chapter describes analytical procedures of the highest potential for analysis of biological (physiological fluids and tissues) and environmental (plants, airborne particulates and dusts, soils and sediments) samples for Pt and Ru used in chemotherapy and for Pt, Pd, and Rh used as components of autocatalysts. 

The quality of analytical results obtained in the analysis of biological and environmental materials substantially depends on the sample preparation procedures applied, particularly when low concentrations of the metals and species of low stability are determined in complex matrices. Concentrations below the detection limits (DLs) of the available instrumental techniques and interfering effects from the matrix components require separation and preconcentration procedures. Instrumental techniques applicable to direct examination of solid materials are valuable for minimizing the effect of sample preparation steps on the quality of obtained results. In the analysis of noble metal samples, in particular those of complex environmental origin, use of such techniques is strongly limited because of interference from matrix components and the heterogeneity of examined materials. 

Chlorination using chlorine attack can be an attractive method for determination of noble metals in samples of complex composition. All noble metals undergo chlorine attack. Binary chlorides or salts dissolved in diluted mineral acids are the products of chlorination. Dry chlorination by chlorine passing over the sample, either alone or mixed with a small amount of NaCl, in an open mbe at 500-600 °C, is the most promising method because of the low amounts of chemicals introduced into the sample, low blanks, and the possibility of direct combination with the detection technique. The effectiveness of such a digestion procedure compared with FA in the analysis of rocks was reported [63]. 

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