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Here a new flow injection system is reported for the preconcentration of technetium by solid phase extraction. The system provides analyte preconcentration, reduces interferences from polyatomic ions, and prevents interaction of concentrated nitric acid with the inductively coupled plasma mass spectrometer. The volume of eluate was significantly reduced by collecting the eluate of the highest analyte concentration in an injection loop followed by transport to the spectrometer with dilute nitric acid. Due to the absence of a suitable standard reference material, the determination of technetium in peat was compared with liquid scintillation spectrometry.

Manganese as an essential element is required by organisms from simple bacteria to plants, animals and human beings. The identification and determination of organic or inorganic manganese forms are important from many viewpoints, such as their bioavailability or bioactivity. A review of the use of different analytical methods, which allow manganese speciation and fractionation in various types of matrices, such as soils, sediments, air, aerosols, water, plants, animals and polluted environmental samples, is presented in this study. The presented approaches assume mainly the use of indirect techniques from simple ones, such as extraction, through multistep procedures to more complex ones, such as hyphenated techniques. Direct analysis of manganese species is also possible, but unfortunately only in some cases and for selected samples. Significance of manganese speciation and fractionation in different areas of life and difficulties in performing such analysis pose a challenge.

Trace elements have an impact on numerous physiological processes. The monitoring of their levels in the organism allows you to detect not only their deficiencies, but also several illnesses. The aim of this study was to compare the levels of essential elements (calcium, magnesium, zinc, copper, iron, manganese) in hair, nails and serum of both patients with laryngeal cancer and healthy people. The determination of six metals was performed by an inductively coupled plasma mass spectrometry (ICP-MS) and an inductively coupled plasma optical emission spectrometry (ICP-OES). The concentration of essential elements in hair and nails of the control group was statistically significantly higher than in the group of patients with laryngeal cancer. In the case of serum, differences were found between the patients and controls in respect of the level of three metals. The results of principal component analysis (PCA) revealed the strong and similar clustering behavior of essential elements in hair and nails. The metals did not correlate between two alternative materials. The present study indicated that, using the level of essential elements in hair and nails as a basis, it is possible to distinguish cancer patients from healthy people. The alternative materials are independent of homeostasis and therefore seem to be more useful in the detection of diseases and mineral deficiencies in human than the classical biological materials, such as blood.

This work was aimed to provide a well-established approach for the quantification of silver sites in zeolites. The experimental procedure based on carbon monoxide sorption in silver exchanged zeolites ZSM-5, Y, and X was monitored by IR spectroscopy. With regard to the Lambert-Beer law the values of the absorption coefficients of the IR bands of CO interacting with exchangeable cations $(Ag^{+})$ and metallic species $(Ag^{0})$ were attained. Subsequently, the concentrations of silver species of different kinds were calculated. The values of the absorption coefficients are valid for zeolites of FAU and MFI topologies; thus, they are argued to be used for zeolites of other structures.

Silica gel was modified via silanization with 3-chloropropyltrimethoxysilane and subsequently Cu(II)-5- dodecylsalicylaldoxime was grafted. Obtained sorbent was applied to on-line copper(II) preconcentration and its FAAS determination. Effective copper(II) elution was observed for 2% v/v nitric acid. The new sorbent exhibits optimal sorption efficiency within pH 5.6 and 7.5. A portion of the sorbent may be used repeatedly for not less than 100 sorptiondesorption cycles. The sorbent indicates high sorption and elution effectiveness of ca. 96 and 99%, respectively. Introduction of a preconcentration step before flame atomic absorption spectrometry (FAAS) copper determination with 60 s loading time resulted in 12-fold increase in the measured absorbance. This could be further raised by extending the loading time. Metals, like Zn(II), Mn(II) and Pb(II) caused negative interference effect while presence of Ca(II) and Mg(II) caused increase in the obtained signals. Copper(II) in samples such as: well water, mineral water, river and tap water was determined via the standard addition method. Detection limit for the proposed procedure was estimated at 1.5 µg L-1 (3σ). Accuracy of the method was assessed via comparison of the results obtained for copper determination in ground water and waste water certificate reference materials with those obtained with the use of a reference method (ICP MS).

For many years, copper has found fundamental application in metallurgy and electrical industry due to its ductility and excellent electrical conductivity. Nowadays, biostatic properties of this element are ex- ploited in fungicides and wood preservatives, and components of water-treatment agents have attracted growing interest, resulting in its spread in various areas of human life. The need for copper determina- tion at lower and lower concentration levels requires the involvement of dedicated analytical tools. Atomic spectrometric methods are still the most frequently used, but, in some applications, both enhancement of selectivity and increase in sensitivity are required and are realized by introducing solid-phase extrac- tion (SPE) with sorbents selective towards copper. We present the most frequently applied sorbents dedicated to copper preconcentration, new trends in the methods for modifying them and the aspect of copper speciation using sorbents. We pay special attention to construction of on-line and off-line SPE set-ups.

A calibration step in an analytical procedure is often not adequately treated, although it is a very important step in the analysis. Also, the approach to the nomenclature seems to be disrespectful. In order to resolve this problem we chose a new classification based on both how the calibration dependence is reconstructed, and how the measurement data is then transformed. In this paper we discussed the steps of a developed calibration procedure in the determination of trace elements in rat brain tissues by the Laser Ablation Inductively Coupled Plasma Time of Flight Mass Spectrometry (LA ICP-TOF-MS) method. The developed calibration procedure uses the long established calibration method - the method of standard addition - although the standard samples are in this case the rat brain tissue samples. The results show the usefulness of the procedure developed in the presented analytical problem related to the analysis of solid samples, which is where the work is original.

The aim of the present work is to study the remains of seven individuals with typical symptoms of tertiary syphilis in terms of mercury content in bones, thereby verifying whether they were subjected to treatment and, if they were, how long their organisms were exposed to toxic mercury fumes. Mercury was used, mainly in the Middle Ages and in the early modern period, as a preventive measure in case of individuals suffering from syphilis, a venereal disease, and also leprosy. Syphilitic patients treated this way should demonstrate increased concentration of mercury in their bones. The skeletons studied in the present work originate from various archaeological sites in southern and north-central Poland. The analyses concerned individuals with diagnosed syphilis as well as healthy individuals who constituted the control group. The analyses were performed by the LA-ICP-MS technique, with the use of laser Nd: YAG, Macro, 266 nm, New Wave, USA, coupled with Spectrometer Elan DRC-e Perkin Elmer, USA. The content analysis of the studied bone material revealed with high probability that the contact method of mercurial treatment was used only in the case of two women from north-central Poland, deceased at the turn of the 15th century at the earliest.

The aim of this study was to find correlations between several studied elements and analyzed materials as well as the application and validation of an analytical method to determine trace elements in hair, fingernails and toenails of healthy volunteers (normal concentration). The method developed covers washing, mineralization and ICP-MS determination of 10 elements (Ca, Cd, Co, Cr, Cu, Fe, Mg, Ni, Pb and Zn) in hair and nails. Concentrations of the selected elements in hair, fingernails and toenails were measured for 24 women and 18 men. Furthermore, a chemometric approach (Principal Component Analysis, PCA) was employed to evaluate the correlations between concentrations of the elements in hair and nails and between these materials. Until now PCA has not been frequently applied in handling and interpretation of the results of analysis of biological materials. However, the results of the present investigation show the high potential of PCA in extraction of valuable information from analytical measurements. Additionally, PCA has become a useful tool for visualization of the obtained results. Moreover, the cluster analysis (CA) was used to group the samples according to gender, taking into account two different groups of elements: essential and toxic.

The paper presents application of a new resin dedicated to copper(II) flow-injection on-line preconcentration prior its flame atomic absorption spectrometric (FAAS) determination. The new sorbent, obtained by suspension polymerization technique, was styrene-divinylbenzene copolymer modified with 5-dodecylsalicylaldoxime-copper(II) complex. In flow mode leaching of initially imprinted Cu(II) ions from polymer beads was effective with 1% (v/v) nitric acid, however for elution of ions retained on the sorbent during the loading process sufficient efficiency was obtained for 0.5% (v/v) nitric acid. The most effective copper(II) sorption was observed within sample pH ca. 6.3 at flow rate 7.5 mL min −1 . Furthermore, preconcentration studies of Cu(II) ions realized in the presence of popular foreign ions like Cd(II), Pb(II), Zn(II), Ni(II), Mn(II), Co(II) did not reveal significant interference. The expected effect of Cu(II)-imprinting was confirmed by higher tolerance level for interferents ions concentration for the new sorbent than for the control polymer. It was found that alkaline metals ions and humic acid had the most relevant influence on copper(II) uptake. Accuracy of the evaluated method was assessed for analysis of water samples (tap and mineral water, river water, artesian water) and certified water reference materials compare them to results obtained by inductively plasma mass spectrometry. The satisfactory relative error values obtained with use of standard addition calibration method, confirms the feasibility of this method for Cu(II) determination in water samples. Application of 120 s sorption time enabled to obtain 74-fold enrichment factor and limit of detection (3 σ ) equal to 0.4 μg L −1 .

A new sorbent – salen impregnated silica gel – was prepared and characterised for application as a minicolumn packing for flow-injection on-line preconcentration of cadmium(II). The system was coupled with flame atomic absorption spectrometer (FI-FAAS). The optimal pH for Cd(II) sorption was in the range of 7.4–8.8 and nitric acid (1%, v/v) was efficient as eluent. Sorption was most effective within the sample flow rate up to 7 mL min−1. Sorption capacity of the sorbent found in a batch procedure was 26.3 µmol g−1 (2.95 mg g−1). Enrichment factor (EF) and limit of detection (LOD) obtained for 120-second loading time were 113 and 0.26 µg L−1, respectively. The sorbent stability in the working conditions was proved for at least 100 preconcentration cycles. The evaluated method was applied to Cd(II) determination in various water samples.

The purpose of this work was to determine trace element levels in urine and evaluate possible associations between urinary iodine concentration (UIC), other trace elements (Cr, Cu, Fe, Mn, Na, Se, Zn), toxic elements (Cd, Pb), anthropometrical measures (body weight and height), glycemic indices (serum insulin and glucose), and several parameters related to thyroid function (thyroid stimulating hormone, free thyroxine, antithyroid peroxidase antibodies, thyroid volume, and thyroid echogenicity) in pregnant women. One hundred sixty-nine participants were recruited. The whole study group, originating from Krakow region, comprised three subgroups belonging to three trimesters: I trimester (n = 28), II trimester (n = 83), and III trimester (n = 58). Trace elements were determined using inductively coupled plasma mass/(atomic emission) spectrometry. Partial least square model was used to reveal correlation structure between parameters investigated, as well as a possible causal relationship between dependent parameters and potentially explanatory parameters. Results obtained for trace and toxic elements in urine were comparable with results of other authors, although the study group was not homogenous. We confirmed (1) low iodine excretion in pregnant women, (2) the existence of statistically significant correlation between UIC and urinary selenium, and (3) lack of correlation between latter parameter and typical indices of thyroid function. Urinary selenium correlated with other urinary trace elements, but physiological significance of this finding remains uncertain. The fact that a large number of pregnant women fail to meet dietary recommendations for iodine is the major reason for concern.

Cadmium (Cd) exerts a detrimental effect on the metabolism of plants, whereas selenium (Se) may protect them against various stressors through its antioxidative activity. In this in vitro study we investigated the impact of Se (2 µM Na2SeO4) on the growth, nutrient (P, S, K, Ca, Mg, B, Mn, Fe and Zn) concentrations and cell integrity of rape (Brassica napus oleifera) and two wheat (Triticum aestivum) genotypes subjected to Cd stress (600 µM CdCl2). Rape accumulated both Cd and Se more than did wheat. In all plants, Cd markedly reduced the biomass, enhanced lipid peroxidation and diminished plasmalemma fluidity. A drop in the K uptake and the reduced plasmalemma permeability diminished the K efflux from the leaf cells. In contrast, Cd elevated S concomitantly with Zn, indicating an activity of detoxifying SH groups and SOD isoenzymes. When added alone, Se promoted the growth of all plants, it enhanced the accumulation of S, but the impact on other nutrients remained minor. In Cd-stressed plants, Se tended to counterbalance the Cd-induced changes in nutrients, it also reduced the lipid peroxidation and exerted positive effects on the cell membrane stability. The Cd stress and the protective role of Se were most evident in rape. The Finnish wheat genotype was less tolerant to Cd than the Polish one.

Microwave closed-system wet digestion procedures for plant samples were examined. Each procedure was tested with samples of tobacco and cabbage, and included digestion by the use of different acids composition, almost complete evaporation of the digest, and then dissolution of the residue in 1% nitric acid. Three microwave digestion programs that varied power, duration, and temperature were used. Closed-vessel reactions followed open-vessel reaction-delay time. Using flame atomic absorption spectrometry on the digests, four or five elements were determined to evaluate effectiveness, precision and accuracy of analytes extraction into solution. After a preliminary study of tobacco digests, the four most effective procedures were chosen, and detailed investigations were carried out on both tobacco and cabbage reference materials. Although all four of the final procedures were accurate, the most precise procedure, with the lowest errors of determination, was using reverse ‘aqua regia’ for tobacco and ‘aqua re...

The comparative responses of ten spring wheat cultivars to water stress were investigated. Wheat plants were cultured under hydroponics conditions (Hoagland nutrient) to the stage of three-leaf seedlings. Then, the water medium was supplemented with PEG (drought) or NaCl (salinity) to obtain a water status equal to - 1.5 MPa. After a 2-day treatment, the changes in the following parameters were determined: fresh and dry weight, macro- and microelement accumulation, membrane injury (elec- trolyte leakage, lipid peroxidation) and fatty acid content of the phospholipid fraction of plasmalemma (in comparison to plants not stressed, taken as a control). Generally, the plants were more significantly influenced by water stress stimulated by PEG than by NaCl treatment, as compared to the plants cultivated in the control media. The results of the decrease in water content in leaves and electrolyte leakage from cells corresponded well with the intensity of lipid peroxidation (determined by malondialdehyde—MDA- content) and were chosen for the selection of investigated genotypes for tolerance to both stresses. The more tolerant genotypes exhibited the opposite changes in phospholipid fatty acid unsaturation for two applied stresses i.e. NaCl treatment caused a decrease in unsaturation whereas in PEG-treated plants an increase in unsaturation was observed. These changes were reversed for less tolerant plants, i.e. NaCl treatment influenced an increase in fatty acid unsaturation whereas in PEG-treated plants a decrease in unsaturation was measured. The ratio of U/S (unsatu- rated to saturated fatty acids) correlated with the total amount of accumulated macroelements. The content of Mg, Ca and S in leaves of plants undergoing both stress factors (NaCl and PEG) dropped whereas the K and P content increased in leaves of wheat seedlings cultured on media containing NaCl only. For microelements, a decrease in the accumulation of these nutrients was detected in all investigated seedlings. However, a greater reduction in the level of these elements occurred in seed- lings grown on media with PEG in comparison to those grown on NaCl containing media.

Manganese, a microelement important for plant metabolism, when accumulated at higher doses, may act as a stress factor. Such action of this element is not fully recognized and is currently being intensively studied. The influence of manganese, at high (1, 2 and 3 mM) concentrations, on the induction of oxidative stress in wheat cells was studied under in vitro conditions. Calli of two wheat cultivars, different in terms of stress tolerance, were cultured for 7 days on Murashige–Skoog media with or without auxin (2,4-D) and with additional Mn supplementation. Changes of malondialdehyde (MDA) concentration and the activity of enzymes (SOD, CAT and POX) involved in oxidative response as well as the accumulation of Mn and elements essential for plant development (Mn, Mg, S, Ca, K, P, Na, Zn, Mo, Cu, Fe) were detected. Moreover, proline and carbohydrate contents were determined to check the induction of osmotic stress. An increase of lipid peroxidation (expressed by MDA content), induced by ROS generation, was smaller in the tolerant (‘Parabola’) cultivar than in the sensitive one (‘Raweta’). The activation of antioxidative enzymes was more effective in the cells of tolerant wheat, where a lower quantity of Mn was accumulated. Mn uptake was correlated with a decrease of an amount of almost all the investigated elements. Auxin presence in the culture media accelerated the stressogenic effect of Mn.

Effects related to the adaptation of wheat to Mn excess were determined by structural and biochemical characterization of chloroplasts obtained from three-leaf seedlings of Mn-treated wheat. Chloroplasts were isolated from two wheat genotypes: sensitive (Raweta) and tolerant (Parabola) cultivated in hydroponic conditions in Hoagland nutrient supplemented with 0 (control), 5, 10, and 20 mmol dm−3 MnSO4. Microscopic observations of the chloroplast structure revealed differences in the size and starch presence between both objects. Changes indicating the stresogenic influence of Mn on Raweta seedlings appeared already at the Mn dose of 10 mmol dm−3, whereas on Parabola, only at 20 mmol dm−3. Biochemical analysis indicated the differences in starch content. Results of measurements of lipid peroxidation, polarity, and electrokinetic potential of chloroplasts point to Mn-stimulated modifications of chloroplast membranes which occurred to be larger for Raweta. The activation of antioxidative enzymes (SOD and POX) shows that ROS are generated under Mn-excess conditions. The content of Mn and Cu, Fe, Mo, and Zn (microelements) as well as Ca, Mg, K, P, and S (macroelements) in chloroplasts was determined by mass (ICP MS) and plasma optic emission (ICP OES) spectrometry. Raweta accumulated greater amount of Mn in comparison with Parabola at all Mn doses in media. Increased concentration of Mn was accompanied with a decrease of uptake other investigated elements (except for K).