ABSTRACT
Approximately 0.25 g of dry plant sample was predigested in 5 mL of mixture HNO3/HClO4 in ratio 7:1 (v/v) overnight at lab temperature. Then 3 mL of acid mixture were added to clean the walls of tube and the contents of the closed Teflon vessel digested in gradient to 100% power after 15 min. and at 100% power for further 25 min. Digestion was accomplished in a Multiwave reaction system (Multiwave PRO, Anthon Paar GmbH, Austria). The cooling was made another 20 min. The samples were filled up to 10 mL volume and analyzed by an AAS spectrophotometer (SenAA, GBS, Australia).
