Lovorka Pitarević Svedružić

ICP-AES analysis of metal content in shell of mussel Mytilus galloprovincialis from Croatian coastal waters.

Metal content in samples of shell of mussel Mytilus galoprovincialis was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The efficiency of conversion of crude samples into solution by acid digestion in an open plate and in a microwave oven was examined by use of certified reference material of marine sediment and laboratory made standards of calcite and aragonite. Influence of high Ca content matrix on emission intensities of Al, Ba, Cd, Cu, Fe, Mg, Mn, Na, Ni, Pb, Sr and Zn was observed as depression of emission signal for most of the measuring elements, ranging from 0.8% to 8%. Greater values were noted at Ba and Ni emission lines. Enhancement of signals was observed for Na and Mg lines. The determination of As, Sb, Se and Sn was performed by HG/ICP-AES. The greater abundance of Sn was found in samples collected near the Al-processing industry centre. No detectable concentrations of As, Sb, and Se were found in shell samples. Results of ICP-AES metal analysis showed that samples collected near harbours, city waste or sewage outlets, and chemical industry centres indicate the certain level of contamination. It is shown that shell analysis provides useful data in determination of marine environment status.

Elemental Composition and Chemometric Characterization of Pyrethrum Plant Materials and Insecticidal Flower Extracts

The elemental composition of native and cultivated pyrethrum plants (Tanacetum cinerariifolium) and their insecticidal extracts obtained from dried flower heads was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The accuracy of the analytical procedure which included pressurized digestion of plant samples in HNO3/H2O2 was tested by certified reference materials. Acceptable recoveries (90–110%) for the majority of elements were obtained measured in a simultaneous multi-element mode. The total pyrethrins content was determined by HPLC and it was 2.09% for cultivated plants and 1.58% for native species. The concentrations of 18 elements and pyrethrin content were subjected to statistical multivariate analysis which showed different patterns among plant parts. The roots were characterized by a combination of loadings of iron, aluminum, nickel, chromium, strontium, and barium, while the stems, leaves, and flowers showed more contributions from sodium, potassium, calcium, magnesium, phosphorus, sulfur, manganese, and copper. A higher loading of pyrethrins was the main characteristic of dried flower extracts. It was also observed that microelements such as copper, aluminum, and iron were more readily transferred into natural insecticide extracts.

Determination of chemical composition of pottery from antic Siscia by ICP-AES after enhanced pressure microwave digestion

This study describes the results of chemical characterization of archaeological pottery excavated at Sisak, Croatia known as prehistoric town Segestica (IV–I century BC) or Siscia, the capital of Roman province Pannonia Savia (I–IV century AD). Chemical composition of pottery shards and a sample of raw clay material was determined by ICP-AES analysis after high pressure microwave digestion. High efficiency of the applied system allows decomposition of ceramics by the use of nitric acid exclusively. All shards excavated from prehistoric, Early-Roman and Roman strata were decomposed without additional load of hydrofluoric acid. The accuracy of the performed procedure was tested by certified reference materials of medium and high silica content. The obtained results of sixteen element concentrations were in good agreement with certified values. Measured concentrations of main, minor and trace elements were subjected to univariate and multivariate statistical analyses. Based on principal component analysis and clustering of data, a grouping of samples in four clusters was established. The results of chemical analysis of ceramic products were found to be comparable to archaeological interpretation that denotes differentiation between local production and imported goods.