MICROWAVE DIGESTION OF BIOLOGICAL-MATERIAL FOR VOLTAMMETRIC TRACE-ELEMENT ANALYSIS

Wet mineralization using microwave irradiation have been applied for t he decomposition of organic samples followed by differential pulse ano dic stripping voltammetry determination of Zn, Cd, Pb and Cu. Digestio ns have been performed in a Milestone rotor (p(max) = 30 bar) and a do mestic microwave oven with a mixture of HNO3-HClO4. Samples have been weighed into quartz crucibles placed inside Teflon vessels and determi nations have been performed in the same crucibles. Standard reference materials (plant, animal tissue, milk powder) have been decomposed und er established conditions.