Comparison of three extraction procedures for quantification of Cu, Mn, Ni, Pb and Zn in the plants

During this research, the content of five potentially toxic elements (Cu, Mn, Ni, Pb and Zn) was determined in different plant material by atomic absorption spectrophotometry after three methods of acid digestion: 1. HNO3+H2O2+HClO4 (10:3:1), 2. aqua regia+H2O2 (5:1), 3. HNO3+H2SO4+HClO4 (5:1:1). Analyzed plant samples were hay and quinoa shoots, vine tree and pear and apple leaves. Additional quality control was done with certified reference sample of the rye grass ERM®-CD281. Obtained results showed that the most effective extraction procedure for quantification of Cu, Mn, Ni and Pb in the examined plant samples was acid digestion with mixture of aqua regia and 30% H2O2. On the other hand, digestion with concentrated nitric acid followed by addition of hydrogen peroxide and perchloric acid was the most efficient procedure in the case of the Zn contents determination.