Use of various spectroscopic techniques (ICP-MS, ICP-OES and AAS) in determination of metals in Elderberry
The purpose of the masterˈs degree is to determine the assay of metals in samples of elderberry. In the first part we analyzed the content of metals in different parts of plant in two parallels: Test roots, D 103 Strawberries, 3/8 Inflorescence, Leaves, Snigra BB stips, Test shoots and 4/16 Bark. Due to the highest differences in metal assay we continued to explore content of metals in bark and young shoots. Bark and young shoots cover the third and fourth generations of elderberry crosses, comprising combinations of two, three or four species: black (Samucus nigra), blue (S. cerulea), red (S. racemosa) and Javanese (S. javanica). Together with its subspecies, we also included an independent type of S. nigra in the study. Some of sampled plants have the same genetic record (same parental structure), but due to genetic segregation, they represent different genotypes. In analysis, we also included some clones (C1). Samples were prepared with classical acid and microwave digestion. We have determined the content of metals using various spectroscopic techniques (ICP-OES, AAAS and ICP-MS). Prior to start of the analysis samples were prepared by acid digestion by heating over the burner (use of H2SO4, HNO3 and H2O2) and the use of MW digestion. We compared the results of the metal content obtained with various spectroscopic techniques.
In scope of masterˈs degree, we also determined linearity, LOD, LOQ, repeatability, interval of confidence and search for an outliner with Dixon and Grubbs test. With the statistical tests: Spearmanˈs coefficient and Kruskal-Wallis test we studied connections between individual elements and the zero hypothesis that the median populations are the same. We also investigated effect of wavelengths on metal concentrations. With digestion with nitrogen(V) acid, various extractions of metals in which different reagents were used, we wanted to determine which metals are present and their assay in samples.
For further analysis, ICP-OES method was chosen due to low detection limit, wide linear concentration range and accuracy. We also performed partial validation of method. Assay of metals in samples was determined with method using calibration curve.
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