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The aim of this study was to propose a complete approach for macroalgae biomass valorization into products useful for sustainable agriculture and environmental protection. In the first stage, the effects of macroalgal extracts and ZnO NPs (zinc oxide nanoparticles) on the germination and growth of radish were examined. Macroalgal extract was produced from freshwater macroalga, i.e., Cladophora glomerata by ultrasound assisted extraction (UAE). The extract was used to biosynthesize zinc oxide nanoparticles. In germination tests, extracts and solutions of ZnO NPs were applied on paper substrate before sowing. In the second stage, sorption properties of macroalga, post-extraction residue, and ZnO NPs to absorb Cr(III) ions were examined. In the germination tests, the highest values of hypocotyl length (the edible part of radish), i.e., 3.3 and 2.6 cm were obtained for 60 and 80% extract (among the tested concentrations 20, 40, 60, 80, and 100%) and 10 and 50 mg/L NPs, respectively. The highest sorption capacity of Cr(III) ions (344.8 mg/g) was obtained by both macroalga and post-extraction residue at a pH of 5 and initial Cr(III) ions concentration of 200 mg/L. This study proves that macroalgae and products based on them can be applied in both sustainable agriculture and wastewater treatment.

Four procedures based on closed-vessel microwave-assisted wet digestion with different oxidative reagents, including HNO3 (P1), HNO3 + H2O2 (P2), aqua regia (P3) and Lefort aqua regia (P4), for preparation of calcium (Ca)-rich materials prior to determination of total concentrations of Al, Ca, Cd, Fe, Mg and P by inductively coupled optical emission spectrometry (ICP OES) were compared. It was found that digestion with Lefort aqua regia (P4) provided the best results for all examined elements, i.e., precision of 0.30–4.4%, trueness better than 2%, recoveries of added elements between 99.5–101.9%, and limits of detection within 0.08–1.8 ng g−1. Reliability of this procedure was verified by analysis of relevant certified reference materials (CRMs), i.e., Natural Moroccan Phosphate Rock—Phosphorite (BCR-O32). Additionally, selection of appropriate analytical lines for measurements of element concentrations, linear dynamic ranges of calibration curves and matrix effects on the analyte response were extensively investigated. Finally, the selected procedure was successfully applied for routine analysis of other Ca-rich materials, i.e., CRMs such as NIST 1400 (Bone Ash), CTA-AC-1 (Apatite Concentrate Kola Peninsula) and NCS DC70308 (Carbonate Rock), and six natural samples, such as a dolomite, a phosphate rock, an enriched superphosphate fertilizer, pork bones, pork bones after incineration, and after steam gasification.

A strategy was developed for the determination of total As in birch saps (BSs) by hydride generation (HG) coupled with inductively coupled plasma optical emission spectrometry (ICP-OES). We proposed and validated a simple and robust HG-ICP-OES method with no need for tedious and long sample preparation before measurements. Corresponding As hydride was generated in reaction with NaBH

The newest achievements in the field of glow microdischarges generated in contact with a flowing liquid cathode (FLC) and a flowing liquid anode (FLA), used as the excitation sources for optical emission spectrometry (OES), were summarized herein. The design of recently reported discharge systems was compared and comprehensively discussed. A lot of effort was devoted to evaluate the effect of selected operating parameters, i.e., discharge voltage and current, sample flow rate, sample pH, jet-supporting gas flow rate, and discharge gap, on the microplasma stability and the intensity of measurable analytical signals. Furthermore, the influence of chemical modifiers, i.e., organic acids, alcohols, and surfactants, aimed at improving the sensitivity and reducing matrix effects, was referred to as well. Finally, the analytical performance and the application of these promising excitation sources for the elemental analysis of different-matrix samples were presented.

Simple, straightforward non-chromatographic method for inorganic arsenic (i-As) determination in rice using species-selective hydride generation (HG) combined with inductively coupled plasma optical emission spectrometry (ICP OES) without prior separation of methylated organoarsenicals (o-As) before measurements was developed and fully validated. i-As [As(III,V)] and o-As (DMA, MMA) species were extracted in aqua regia that oxidized As(III) to As(V), while integrity of both o-As forms was preserved. Arsenic hydrides from i-As were generated in reaction with NaBH4 (1%) in strong acidic conditions (10 mol L−1 HCl) after pre-reduction of As(V) to As(III) in a KI (0.5%)-ascorbic acid (2%)-HCl (3 mol L−1) mixture. Reactivity of As species toward HG under conditions of a rice matrix was investigated in order to improve detectability and selectivity of i-As when o-As coexists. Interferences related to contribution of DMA and MMA to the As signal recorded for i-As were pointed out. Limitations of the method for DMA and matrix effects for MMA were found advantageous to selectively measure i-As by HG-ICP OES. No matrix effects on i-As allowed to use external calibration for its quantification. Detection limit of 0.28 ng g−1 (5.6 ng g−1 in original sample), precision

A simple and fast, non-digestion treatment, and fully validated preparation procedures of dialyzable and non-dialyzable fractions of brews of ground (GCs) and instant (ICs) coffees prior to their elemental analysis (Al, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Ni, Sr, and Zn) by flame atomic absorption spectrometry (F AAS) and inductively coupled plasma optical emission spectrometry (ICP OES) was developed. Three different procedures: wet digestions (P1), direct analysis (P2), and acidification with HNO3 (P3) were tested. Among tested procedures, the direct analysis (P2) gave the most satisfactory results, i.e., precision from 0.54% (Fe) to 5.9% (Cu), recoveries ranging between 98.0% (Sr) and 104% (Al), detection limits within 0.095 (Ba)–1.8 (Ni) μg L−1, and quantification limits from 0.32 (Ba) to 6.0 (Ni) μg L−1. The chosen procedure was applied to determine bioaccessibility of 11 elements in GCs and ICs coffees using in vitro gastrointestinal digestion. Average contributions of the bioaccessible fraction (%) of elements in brews were as follows: Al (19.0, 23.0), Ba (42.8, 48.4), Ca (35.0, 38.9), Cr (

This review article is focused on element composition of medicinal plants and herbs as well as their decoctions and infusions determined by atomic spectrometry methods. Considering quality and safety of these herbal beverages, widely practiced in herbalism for medicinal and supplementing purposes, element analysis is important, and quality of its results should not raise any doubts about reliability. Hence, original researches devoted to element analysis of decoctions and infusions of medicinal plants and herbs, published after 2000, have been surveyed in details, particularly focusing on sources of elements in medicinal plants, their availability for the intake during preparation of infusions and decoctions as well as different methodological aspects related to element analysis by atomic spectrometry, including sample pretreatment and preparation before measurements, calibration methods used, and verification of reliability of results.

Consumption of honey cannot raise any concern about its wholesomeness, safety and quality in reference to the content of different contaminants, particularly trace and hazardous elements. Element analysis of honey by atomic and mass spectrometry methods is an important part of its quality and safety. The present paper comprehensively reviews recent achievements in element analysis of honey that have been reported since 2012. The survey is focused on different research aspects of such analysis, including assessment of biological and geographical origin of honey by using chemometric methods, quality and safety of honey, and sample preparation of honey prior to element analysis by atomic and mass spectrometry methods. Calibration strategies and ways of quality assurance and control of the results are surveyed as well.

A systematic study of hydride generation (HG) of As, Bi, Sb and Se from solutions containing As(III), As(V), Bi(III), Sb(III), Sb(V), Se(IV) and Se(VI) was presented. Hydrides were generated in a gas-liquid phase separation system using a continuous flow vapor generation accessory (VGA) by mixing acidified aqueous sample, HCl and sodium borohydride reductant (NaBH4) solutions on-line. For detection, a simultaneous axially viewed inductively coupled plasma optical emission spectrometer (ICP-OES) was applied. Effects of the HCl concentration (related to sample and additional acid solutions) and type of the pre-reducing agents used for reduction of As(V), Sb(V) and Se(VI) into As(III), Sb(III) and Se(IV) on the analytical responses of As, Bi, Sb and Se were studied and discussed. Two compromised HG reaction conditions for simultaneous measurements of As+Bi+Sb (CC1) or As+Sb+Se (CC2) were established. It was found that choice of the pre-reductant prior to formation of the hydrides is critical in obtaining the dependable results of the analysis. Accordingly, for a As(III)+As(V)+Bi(III)+Sb(III)+Sb(V) mixture and using CC1, thiourea/thiourea-ascorbic acid interfered in Bi determination and hence, total As+Sb could be measured. If L-cysteine/L-cysteine-ascorbic acid were used, measurements of total Bi+Sb was possible in these HG reaction conditions. For a As(III)+As(V)+Sb(III)+Sb(V)+Se(IV)+Se(VI) mixture and using CC2, thiourea/thiourea-ascorbic acid and L-cysteine/L-cysteine-ascorbic acid influenced HG of Se but ensured total As+Sb determination. In contrast, heating a sample solution with HCl, although did not pre-reduce As(V) and Sb(V), assured quantitative reduction of Se(VI) to Se(IV). Finally, considering all favorable pre-reducing and HG conditions, methodologies for reliable determination of total As, Bi, Sb and Se by HG-ICP-OES were proposed. Strategies for single-, two- and three-element measurements were evaluated and validated, obtaining the detection limits (DLs) below 0.1ngg-1 and precision typically in the range of 1.4-3.9% RSD.

The effect of different interfering elements, i.e., Na, K, Mg, Ca, Al, Cu, Fe, Mn, Ni, and Zn, on the analytical performance of flowing liquid anode atmospheric pressure glow discharge optical emission spectrometry (FLA-APGD OES) was extensively studied. In the presence of interfering ions, the emission from analytes was suppressed by ∼10% in the case of Hg and Tl, ∼20% for Cd and Ag, and up to ∼80% for Zn and Pb. This study revealed that interfering elements did not affect the atomization/excitation conditions, and the reason for the observed decrease in analytical response was the impaired efficiency of analytes transport from liquid to plasma phase. To reduce matrix effects, the use of different masking agents capable of complexing the interfering ions, e.g., organic acids, crown ethers, chelating agents, and other compounds, was investigated. FLA-APGD appeared to be quite susceptible to the presence of masking agents and only their small amounts could be added (limiting the effectiveness of this approach). Despite this, it was possible to significantly reduce the matrix effects originating from transition metals and alkali/alkaline earth metals. Based on the results presented herein, different sample treatment procedures, aimed at the minimization of matrix effects in microplasma excitation sources, can be developed. As an example, a method for the determination of trace amounts of Zn and Pb in the Fe-rich matrix has been shown. By the use of the selected masking agents, the recovery of Zn and Pb was improved 5.6-fold (from 10.4 to 57.8%) and 2.8-fold (from 13.6 to 38.0%), respectively. Despite the presence of Fe-rich matrix, the detection limits of Zn and Pb were quite low (0.1 and 0.8 μg L−1, respectively) and they were apparently lower than offered by ICP OES.

Background and aim Bee pollen is recognized to be a source of different nutrients, including minerals. As a food supplement, its quality and safety due to concentrations of essential macro- and microelements, and harmful trace elements has to be verified. Fast and simple element analysis of bee-collected pollen can be regarded as an important part of its quality assurance and control. The present study aimed at developping a new method for determination of selected elements (Ca, Cu, Fe, Mg, Mn, Zn) of bee pollen based on solvent extraction and completely avoiding a high temperature treatment with concentrated reagents. In addition, in vitro gastrointestinal digestion was used to assess bioavailability of elements from this food supplement. Methods Bee pollen samples were dried and pulverized. Total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn were determined by flame atomic absorption spectrometry (FAAS) in sample solutions obtained by wet digestion (WD) in concentrated HNO3 or alternatively by solvent extraction (SE) with diluted solutions of HNO3. Gastrointestinal digestion was mimicked using simulated solutions of gastric and intestinal juices followed by determination of Ca, Cu, Fe, Mg, Mn and Zn concentrations in the bioaccessible fraction by FAAS. Results A new simple and fast method for determination of total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn in bee pollen was developed and validated. The method combined room temperature, two-hour SE with 0.5 mol L−1 HNO3 with FAAS measurements versus simple standard solutions. It provided precision within 1–5 % and trueness better than 8%, and was shown to be suitable for fast analysis of different polyfloral bee pollens. In vitro gastrointestinal digestion revealed that elements were well (70–85 % for Ca, Mg) and fairly (27–43 % for Cu, Fe, Mn, and Zn) bioaccessible from bee pollen. By pouring with water and swelling overnight, bioaccessibility of studied elements from such prepared bee pollen was increased on average by less than 15 % (Mn), 20 % (Ca, Cu, Fe, Zn) or 30 % (Mn). Conclusions Avoiding long-lasting, high-temperature wet digestion with concentrated reagents, the proposed sample treatment along with FAAS provided precise and true results of total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn in bee pollen. The method was simple and fast, and enabled to analyze a higher number of samples. Simulated gastrointestinal digestion of bee pollen have shown for the first time that Ca and Mg are the most bioaccessible from this bee product. Bioaccessibility of Cu, Fe, Mg, and Zn from bee pollen are close to or lower than 40 %.

A new simple and rapid method for the determination of the total concentrations of Cu, Fe, Mn, and Zn in beetroot juices by flame atomic absorption spectrometry was developed and validated. The method included a very simple sample preparation, i.e., the two-fold dilution and acidification of the samples with HNO3 to 1 mol&middot, L&minus, 1 and provided the precision within 2%&ndash, 3% and the trueness better than 6%. The method was applied for the rapid screening analysis of the different commercially available beetroot juices. The chemical fractionation of Cu, Fe, Mn, and Zn was also proposed by the two-column solid-phase extraction with the reversed-phase and cation exchange tubes. It was revealed that Cu, Fe, Mn, and Zn were primarily in beetroot juices in the form of the organically bound forms, contributing to the distinguished hydrophobic and residual fractions. The sums of the mean contributions of both fractions were up to 98% (Cu, Fe, Zn) and 100% (Mn), pointing out that no labile nor unbound forms of the studied metals were present in the matrix of beetroot juices.

A fast and straightforward sample preparation procedure of the dialyzable fraction of infusions of teas prior to their analysis on Al, Ba, Ca, Cu, Fe, Mg, Mn, Ni, Sr, and Zn contents by flame atomic absorption spectrometry (FAAS) and inductively coupled plasma optical emission spectrometry (ICP OES) was developed and validated. The proposed methodology was based on acidification with HNO3 only and demonstrated good analytical performance, i.e., precision (0.80–5.0%), accuracy (

Continuous flow (CF) hydride generation (HG) using a vapor generation accessory (VGA) coupled to a simultaneous axially viewed inductively coupled plasma optical emission spectrometer (ICP OES) for the ultrasensitive measurement of As, Bi, Sb and Se was investigated. Hydrides were generated in a gas–liquid phase separation system by mixing acidified aqueous sample, additional HCl and reductant (NaBH4) solutions on-line. Instrumental (emission line wavelength, RF power, and flow rates of the sample and waste solutions, along with the sample read delay and wash times) and chemical (concentrations of NaBH4 and HCl in the sample (S) and additional acid (A) solutions) variables affecting the effectiveness of HG were examined to achieve the optimum conditions for single- and multi-element analysis. The limitations of the HG reaction due to potential interference effects between the hydride-forming elements were identified. Satisfactorily, As and Sb hydrides could be generated in a wide range of HCl concentrations either in the S solution or the A solution, i.e. 1–6 (S) or 5–10 (A) mol L−1 HCl. For Bi and Se, HG depended strongly on the acidity and the optimum HCl concentrations for both elements were completely opposite. HG for Bi was the best at the lowest acidity (1 (S) and 5 (A) mol L−1 HCl), whereas the maximum Se responses were acquired using the highest HCl concentrations (6 (S) and 10 (A) mol L−1 HCl). Compromised conditions for the simultaneous measurement of As + Bi + Sb or As + Sb + Se, without any adverse interactions between the elements, were successfully established with an analysis time of ∼2 min per sample. Under these conditions, the detectability of all the elements was improved greatly (2 orders of magnitude versus ICP OES). Linear concentration ranges (0–20 ng g−1), detection limits from 0.027–0.099 ng g−1 and a precision better than 2% (as RSD) were achieved.

An analytical scheme for physical fractionation of Al, Ba, Ca, Co, Fe, K, Mg, Mn, Na, Ni, Sr and Zn in ground roasted and soluble coffees brews was proposed. It was based on ultrafiltration through five ultrafiltration membranes having molecular weight cut-offs of 5, 10, 30, 50 and 100kDa. The highest "100kDa" and the lowest "5kDa" molecular weight fractions were established to differentiate the studied coffees brews the most. Al, Cu, Fe and Ni were mostly associated with the "100kDa" fraction, while Co, K, Mg and Na - with the "5kDa" fraction. For Ba, Ca, Mn, Sr and Zn, "100kDa" and "5kDa" fractions contributions were equally accounted. The physical fractionation pattern of selected metals was convenient for discovering important features of brews of both coffee types and differences between them by principal component analysis and then classifying them by linear discriminant analysis.

A simple, non-digestion treatment of brews of ground roasted and instant coffees prior to their analysis on the content of Ca, Fe, K, Mg and Na (with flame atomic absorption spectrometry) and Al, Ba, Cd, Co, Cr, Mn, Ni, Pb and Sr (with inductively coupled plasma optical emission spectrometry) was proposed. Three different sample preparation procedures of brews, including acidification with HNO 3 and aqua regia (both at 0.25, 0.50 and 1.0 mol L − 1 ) and direct analysis of untreated beverages, were compared. Under selected conditions, i.e . , using acidification of brews with HNO 3 to 0.25 mol L − 1 , precision (as relative standard deviation) from 0.2 to 8.7% and detection limits between 0.036 (Sr) and 36 (Fe) ng mL − 1 were achieved. Accuracy of the chosen procedure was verified by comparing obtained results with those assessed using open-vessel wet digestion. Eighteen different coffees marketed in Poland were analyzed with the use of the proposed procedure. Concentrations of selected metals (Al, Ca, Co, K, Mg, Mn, Ni) were effectively used to classify brews of analyzed coffees by principal component analysis, factor analysis and hierarchic cluster analysis.

A direct analysis of instant coffee brews with HR-CS-FAAS spectrometry to determine the total Ca, Fe, Mg and Mn content has been developed and validated. The proposed method is simple and fast; it delivers good analytical performance; its accuracy being within -3% to 3%, its precision--2-3% and detection limits--0.03, 0.04, 0.004 and 0.01 mg l(-1) for Ca, Fe, Mg and Mn, respectively. In addition, Ca, Fe, Mg and Mn bioaccessibility in instant coffee brews was measured by means of the in vitro gastrointestinal digestion with the use of simulated gastric and intestinal juice solutions. Absorption of metals in intestinal villi was simulated by means of ultrafiltration over semi-permeable membrane with a molecular weight cut-off of 5 kDa. Ca, Fe, Mg and Mn concentrations in permeates of instant coffee gastrointestinal incubates were measured with HR-CS-FAA spectrometry.

The applicability of the hydride generation (HG) sample introduction technique combined with different spectrochemical detection methods for non-chromatographic speciation of toxic As species, i.e., As(III), As(V), dimethylarsinate (DMA) and monomethylarsonate (MMA), in waters and other environmental, food and biological matrices is presented as a promising tool to speciate As by obviating chromatographic separation. Different non-chromatographic procedures along with speciation protocols reported in the literature over the past 20 year are summarized. Basic rules ensuring species selective generation of the corresponding hydrides are presented in detail. Common strategies and alternative approaches are highlighted. Aspects of proper sample preparation before analysis and the selection of adequate strategies for speciation purposes are emphasized.

A new method for determining total concentrations of Ca, Cu, Fe, Mg, Mn, and Zn in bee-collected pollen by line source-flame atomic absorption spectrometry (LS-FAAS) combined with ultrasound-assisted solvent extraction (UAE) at a sample preparation stage was developed. A Box-Behnken response surface design along with individual and composite desirability functions were applied to establish optimal conditions of the UAE procedure. Under optimal conditions, i.e., sonication of samples with a 1.1 mol L−1 HNO3 solution at 40 °C and for 15 min (for Ca, Cu, Mg, Mn and Zn) or a 0.9 mol L−1 HNO3 solution at 65 °C and for 15 min as well (for Fe), the method was verified to be precise (related standard deviations within 2–4%) and true (relative errors from −5% to +4%). Limits of detection (LODs) of studied metals were within the μg g−1 range. The developed method was used in very fast and simple analysis of ten different dried bee pollens collected in the summer of 2019.

Comparison of leachability of a set of 31 elements from ashes prepared by laboratory-scale experiments of incineration and allothermal steam gasification of the residual from mechanical treatment of municipal solid waste (RMT-MSW) has been discussed in terms of the oxygen potential ( R T l n p O 2 ) of high temperature (HT) process. Both incineration and steam gasification enable elimination of organic components and carbonaceous residue from the waste. The essential difference between ashes from oxygen incineration and steam gasification consists in (1) higher leachability of metals from gasification ash by diluted (2 M) inorganic acids (HCl, HNO3) and (2) preservation of metallic form of copper in gasification process. Grinding and fractioning of ashes revealed that pieces of metallic Al were accumulated mainly in the coarser grains, but also in fine fraction 0.16 0.50 mm after incineration and 63% of Al, 84.% of Cu and 80% of Zn – in the ash grains o > 0.16 mm after gasification, with 3.80% and 14.8% of the ash mass, respectively. Contrary to incineration, 82% of copper was accumulated in fraction 0.16

A reliable method of the multi-element analysis of black and green teas, based on the ultrasound-assisted solubilisation of samples in aqua regia, was developed and validated for the determination of Ca, Fe, K, Mg, Mn and Na by flame atomic absorption spectrometry and Al, Ba, Cd, Co, Cr, Cu, Ni, Pb, Sr and Zn by inductively coupled plasma optical emission spectrometry. The proposed alternative sample preparation procedure was fast, straightforward and inexpensive in reference to amounts of reagents used and the equipment required. It gave results statistically identical to those achieved with the reference procedure, i.e., the microwave-assisted wet digestion, validated by the analysis of a certified reference material of tea leaves (INCT-TL-1). Its analytical performance was also good and demonstrated by the precision (0.2–8.9%) and the accuracy (from − 9.9 to + 1.2%) of results. Recoveries of added metals were in the range of 98.1 to 104%. Limits of quantification of studied metals were in the following ranges: 0.1–2.4 ng mL− 1 (Ba, Cd, Co, Cr, Cu, Ni, Sr and Zn), 5.1–25 ng mL− 1 (Al, K, Mg, Mn, Na and Pb) and 75–120 ng mL− 1 (Ca and Fe). The procedure was used for the analysis of 20 samples of different bagged and leaf black and green teas available in the Polish market. Concentrations of selected metals (Al, Cr, Fe, K, Mg, Mn, Na, Sr) were applied for the successful grouping of analyzed teas into four certain classes using the principal component analysis and the linear discriminant analysis.

Rice (Oryza sativa L.) is a bio-accumulative plant for arsenic (As), particularly the most toxic inorganic As species (i-As), and the main contributor to i-As intake among agricultural products. The analytical process for determination and speciation of As in rice is complex. Different aspects have to be considered, including detection method, calibration strategy, sample-treatment and preparation procedures, and quality assurance and quality control of results. It is well known that sample preparation is a critical step in the whole analytical chain, so this review surveys achievements in analysis of rice for the content of total As and the species of As reported in the past 15 years using spectrochemical techniques. We discuss different sample-preparation procedures, with their advantages and drawbacks. We highlight common strategies and alternative approaches to speciation analysis of As.

In the quest for good health, consumption of fruit juices is an excellent option. As a cocktail of nutritionally important compounds, including various essential elements, fruit juices are an integral part of the balanced-diet. In order to attain the nutritional elemental composition of this beverage, knowledge about all the elements contained must be gained, including those present at (ultra)trace levels. Among them, Se is a complex constituent with a double behavior, essential or toxic, depending on its concentration and chemical form. The determination of trace and ultra-trace amounts of Se in foods is a challenge. Precise and accurate methods are necessary in order to obtain reliable results. Hence, the present chapter is aimed at summarizing achievements to date in the determination and speciation of Se in fruit juices using spectrochemical techniques. In addition, beneficial effects related to the Se presence (originally or supplemented) in fruits juices are pointed out.

A simple method of simultaneous determination of aluminum (Al), barium (Ba), calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), nickel (Ni), strontium (Sr) and zinc (Zn) in brews of ground and soluble coffees was proposed. It relied on acidification of brews with HNO3 to 1.3 mol L-1 and their analysis by inductively coupled plasma optical emission spectrometry. Precision of 0.1-9% and detection limits from 0.07 ng mL-1 (Sr) to 3 ng mL-1 (Ni) were achieved. Trueness of the method was verified by comparison of results with those achieved with wet digestion and by the recovery study, and was better than 5%. Additionally, chemical fractionation by tandem solid phase extraction with reverse-phase and strong cation-exchange extraction tubes was carried out. Differences in chemical fractionation patterns, particularly the residual fraction, was useful for differentiation of ground and soluble coffees by analysis of variance, principle component analysis and hierarchical clustering analysis.

Various sample preparation procedures for the simultaneous determination of As, Sb and Se in fruit juices by hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP-OES) were examined. Applicability of total wet digestion with HNO3/H2O2, partial decomposition (solubilisation in aqua regia), 1:1 dilution with 2% (v/v) HNO3 and direct analysis were evaluated. Hydrides were generated in the reaction of an acidified sample with NaBH4 after pre-reduction with KI-ascorbic acid for total As and Sb, and boiling with HCl for total Se. Best results, i.e. limits of detection (LODs) of 0.51-0.73 ng mL(-1), precision (RSD) within 1.7-3.6% and recoveries for spiked samples between 101% and 106% were found using aqua regia treatment. This procedure simplifying and improving sample preparation step prior to As, Sb and Se measurements in fruit juices by HG-ICP-OES, thus could be adequate for the routine analysis in terms of the quality control of these drinks.

Sample preparation procedures for the determination of As, Sb, and Se in carrot-fruit juice by hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP OES) were examined. The applicability of a partial decomposition using aqua regia and simple dilution with a 2% (v/v) HNO3 solution were tested and compared to a traditional treatment based on the wet digestion with a HNO3/H2O2 mixture. The pre-reduction and hydride generation reaction conditions were evaluated. Under the optimal conditions, the hydrides were produced in the reaction of an acidified sample with NaBH4 after pre-reduction with ascorbic acid [0.5% (m/v)] and KI [0.5% (m/v)] in 3 mol L−1 HCl for total As and Sb, and boiling with HCl (6 mol L−1) for total Se. The best results were obtained for the aqua regia procedure, resulting in limits of detection (LODs) between 1.2–2.4 ng g−1 in the samples and recoveries from 90.9% to 109.1%. The method was successfully applied (without matrix effects) for the determination of A...

We overview the literature available in the past 10 years relevant to chemical-vapor generation (CVG) of transition metals in analytical atomic spectrometry. We focus attention on chemical and physical parameters facilitating reaction efficiency, and other experimental conditions affecting efficient separation and transportation of the volatile species generated. We discuss the overall efficiency of the process and the susceptibility to interferences in the liquid and gaseous phases with respect to the two-step mechanism of the generation of volatile species and the chemical nature of analyte vapors. We highlight the role of reaction enhancers, such as complexing reagents, surfactants, dispersed metals and ionic liquids. Finally, we give examples of analytical figures of merit and analytical applications of CVG with different methods of atomic spectrometry.

The knowledge about mineral content of slim teas is of great importance since the consumption of these beverages has rapidly increased for the past several years. An increasing popularity of these tea products is mainly attributed to their nutritional properties, flavor, taste and health effects. Therefore, the main goal of the present work was to develop a precise and accurate method of the multi-element analysis of slim teas by inductively coupled plasma optical emission spectrometry (ICP OES) without the need for a laborious and tedious sample treatment preceding spectrometric measurements. Five sample preparation procedures, i.e., the total decomposition in a mixture of HNO3 and H2O2 solutions using closed vessel microwave-assisted or open vessel hot-plate systems, the solubilisation in aqua regia or a tetramethyl ammonium hydroxide solution and the extraction in a diluted HNO3 solution, were compared. The performance of the compared procedures was determined in terms of the precision and the accuracy of results achieved and limits of detection of elements. It was found that the solubilisation in aqua regia gave the best results, i.e., limits of detection between 0.15 and 98.4 ng l−1, the precision within 0.6−3.0 % and the accuracy better than 5 %. The developed method of the analysis, being a useful alternative to time-consuming wet digestion procedures, was successfully applied to the analysis of five slim tea products.

Information on the concentration of major, minor and trace elements in fruit juices is very important because the popularity of these beverages and the rate of their consumption have rapidly increased in the past 20 years. For the overwhelming majority of cases, the elemental analysis of fruit juices is carried out using spectrochemical analytical methods, which normally require samples of fruit juices to be prepared by decomposing their organic matrix and releasing elements in a form suitable for measurement. This review covers different aspects of the elemental analysis of fruit juices and the societal implications related to the presence of various elements in these beverages. We review in detail sample-preparation procedures executed before the elemental analysis together with calibration strategies used, and quality assurance and quality control of results.

A fast and straightforward method of the analysis of coffee infusions was developed for measurements of total concentrations of Ca, Cu, Fe, Mg, Mn and Zn by flame atomic absorption spectrometry. Its validity was proved by the analysis of spiked samples; recoveries of added metals were found to be within 98-104% while the precision was better than 4%. The method devised was used for the analysis of re-distilled water infusions of six popular ground coffees available in the Polish market. Using the mud coffee preparation it was established that percentages of metals leached in these conditions varied a lot among analysed coffees, especially for Ca (14-42%), Mg (6-25%) and Zn (1-24%). For remaining metals, the highest extractabilities were assessed for Mn (30-52%) while the lowest for Fe (4-16%) and Cu (2-12%). In addition, it was found that the water type and the coffee brewing preparation method influence the concentration of studied metals in coffee infusions the most.

Four sample preparation procedures: wet digestion with HNO 3 /H 2 O 2 (P1), 1:1 dilution with 2% HNO 3 and latter centrifugation (P2) or filtration (P3) and direct analysis after centrifugation (P4) for the determination of total Al, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb, Sr and Zn in fruit juices by inductively coupled plasma atomic emission spectrometry (ICP OES) were compared. Precision (RSD), accuracy (by standard addition or recovery) and limit of detection (LOD) were used to evaluate characteristics of the procedures. Dilution with 2% HNO 3 and centrifugation (P2) provided the best results, i.e. LODs between 0.11 and 108 ng mL −1 , RSDs of 1% and 5% and accuracy better than 5%. This procedure was also simple, fast and could be applied for routine analysis. Element concentrations agreed with those after wet digestion, therefore the procedure can be alternatively used instead of conventional sample treatment. Several commercial juices were analysed with this procedure.

Tea made from Camellia sinensis plant is one of the most widely consumed beverages worldwide. It is recognized as a rich source of various elements, including those being essential to human health and also toxic that the plant may accidentally take up during the growth period and which can have adverse effects on the human well-being. Due to the habitual drinking of tea infusions, the determination of the mineral content in tea is of a great importance in order to control the quality and the safety of this product or to judge its nutritional value. In general, atomic and mass spectrometries are commonly used for the elemental analysis of tea leaves and commercial teas. Although these analytical techniques are useful in measurements of the total concentration of elements, they usually require samples to be properly pre-treated prior to spectrochemical measurements. Because the sample preparation of tea is the most critical step of the whole analytical chain, this review has been attempted to survey different preparation procedures of tea samples carried out before the element analysis. Common strategies aimed at decomposing samples through dry and wet digestions are described in details and compared in reference to their advantages and drawbacks. Recent, alternative methods of the sample treatment and the analysis by spectrometry techniques are also highlighted. The effect of the selection of certain sample preparation procedures on the reliability of analytical results and manners of the control and the assurance of their quality are also considered.

A method for the determination of total inorganic arsenic and selenium in slim instant coffees using hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP-OES) was proposed. Various sample preparation procedures, including the traditional total decomposition by the hot-plate or microwave heating in a HNO3/H2O2 mixture and alternative procedures based on the solubilisation in aqua regia or tetramethyl ammonium hydroxide (TMAH) and the dilution only with water or a low concentrated HNO3 solution were examined and compared. Corresponding As and Se hydrides were generated in the reaction of an acidified sample solution with the NaBH4 reductant in the presence of antifoam A. A small sample preparation with aqua regia in an ultrasonic bath followed by the pre-reduction with KI–ascorbic acid in the HCl medium for total As and the boiling with HCl for total Se were found to be optimal. The external calibration using standards treated and measured as the same as samples were applied for the analysis. Limits of detection (LODs) of 0.96 and 0.55 ng ml−1 were assessed for As and Se, respectively. The precision (as the relative standard deviation [RSD]) was within 1.6–7.1 %. The accuracy of the method was confirmed by the recovery test and the analysis of a standard reference material (non-fat milk powder, SRM 1459). The developed procedure was applied for the analysis of six commercial instant slim coffee products available in the Polish market and it was found that these products contain traces of As (0.114–0.247 μg g−1) and Se (0.089–0.137 μg g−1).

A simple and fast method of the determination of total Mn in infusions of ground coffees was proposed and included the acidification of infusions with HNO3 followed by the analysis by flame atomic absorption spectrometry. The method provided the precision and the accuracy better than 3 %. In addition, chemical and physical fractionation patterns of Mn in coffee infusions were assessed using solid phase extraction and ultrafiltration-based procedures, respectively. It was found that Mn in infusions of ground coffees is predominantly present in the form of cationic (64–81 % of the total content) low molecular weight (61–68 % of the total content) species. This points out that this metal is highly bioaccessible from the coffee brew.

An analytical scheme for the physical fractionation of Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Sr and Zn in black and green teas infusions was proposed. It was based on the ultrafiltration/centrifugation through five membranes having molecular weight cut-offs of 100, 50, 30, 10 and 5 kDa. The concentrations of the studied metals in the highest and the lowest molecular weight fractions were found to classify and discriminate the analyzed teas infusions much better than the total metals concentrations. The differences in the physical fractionation patterns of these metals assessed for both tea varieties was profound and let to simply classify the infusions of different black and green teas by principal component analysis and linear discriminant analysis.

Elements in tea infusions may be present in the form of various species with different mobility, availability, and biological activity. As a result, actual impact of the consumption of this beverage on human health cannot be anticipated on the basis of measurements of total concentrations of elements. Nevertheless, this type of the elemental analysis is generally found in the relevant literature and its results are used to judge the safety of tea according to accepted health and nutrition standards or estimate the coverage of recommended daily allowances for elements. Such an approach is not entirely justified because the bioaccessibility and bioavailability of elements from tea can be dependent on their ultimate speciation forms. The need for reliable information on the functional speciation of elements present in tea, the most popular beverage in everyday life, is obvious in terms of the comprehension of the nutritional value and safety of tea. This review article covers the topic of the speciation and ...

A non-alcoholic beverage, tea made from leaves of the Camellia sinensis plant is a potentially rich source of dietary important elements and is consumed by nearly half the worlds population. Of the types of tea, black, oolong and green teas are the most popular, so knowledge about their elemental characteristics is especially important. Habitual drinking of tea infusions may significantly contribute to daily dietary requirements of elements or lead to accumulation of elements and intoxication under overdose conditions. It is especially important that toxic and/or heavy metals, which may be retained by tea plants to a great degree, can have adverse effects on human well-being and health. Accordingly, accurate, precise determination of the mineral content of tea leaves from which tea is made, teas available commercially and their infusions allows us to assess exposure to non-essential elements and to judge the nutritional value of tea reliably. Different instrumental techniques are used for elemental analysis, but atomic and mass spectrometries are preferred most. This review surveys the elemental analysis of teas and their infusions, and the consequences of the presence of various elements in this beverage. We also consider sample-preparation procedures before analysis, the results of analysis and the manner of controlling and assuring the quality of those results. a 2012 Elsevier Ltd. All rights reserved.

Four digestion procedures have been tested to verify their applicability to the determination of major and trace elements (Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, Ti, V, Zn) in a spent catalyst by inductively coupled plasma optical emission spectrometry (ICP-OES). Two digestion procedures have been carried out in a closed microwave system using: (1) HCl+HNO(3)+H(2)O(2); (2) HNO(3)+HF, whereas the remaining two in an open system using: (1) aqua regia+NH(4)F, HNO(3), H(2)SO(4); (2) HF+HClO(4), H(3)BO(3), HCl. Among these four procedures the microwave digestion system (1) gave the best recovery results. The quality of the analytical results has been evaluated by the analysis of the CTA-FFA-1 Fine Fly Ash Certified Reference Material. A good agreement between the measured and reference values was found for almost all elements. The precision was assessed from the replicate analyses of microwave digestion (1) system and was found to be less than 5% of the relative standard deviation (R.S.D.).

Elemental analysis of herbal teas and their tisanes is aimed at assessing their quality and safety in reference to specific food safety regulations and evaluating their nutritional value. This survey is dedicated to atomic spectroscopy and mass spectrometry element detection methods and sample preparation procedures used in elemental analysis of herbal teas and medicinal plant formulations. Referring to original works from the last 15 years, particular attention has been paid to tisane preparation, sample matrix decomposition, calibration and quality assurance of results in elemental analysis of herbal teas by different atomic and mass spectrometry methods. In addition, possible sources of elements in herbal teas and medicinal plant formulations have been discussed.

A simplified alternative to the wet digestion sample preparation procedure for roasted ground and instant coffees has been developed and validated for the determination of different elements by inductively coupled plasma optical emission spectrometry (ICP-OES) (Al, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, Zn) and flame atomic absorption spectrometry (FAAS) (Ca, Fe, K, Mg, Na). The proposed procedure, i.e. the ultrasound-assisted solubilisation in aqua regia, is quite fast and simple, requires minimal use of reagents, and demonstrated good analytical performance, i.e. accuracy from -4.7% to 1.9%, precision within 0.5-8.6% and recovery in the range 93.5-103%. Detection limits of elements were from 0.086 ng ml(-1) (Sr) to 40 ng ml(-1) (Fe). A preliminary classification of 18 samples of ground and instant coffees was successfully made based on concentrations of selected elements and using principal component analysis and hierarchic cluster analysis.

A simple and fast method for the determination of total concentrations of Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, P, Sr, and Zn in wheat crispbreads using inductively coupled plasma-optical emission spectrometry was developed. Initially, three different sample preparation procedures, i.e., microwave-assisted digestion in an HNO3 and H2O2 mixture and solubilization in aqua regia or tetramethylammonium hydroxide solution were compared. The performance of these procedures was evaluated for precision, accuracy, and LOD of the elements. It was established that the application of aqua regia allows determining elements with LOD within 0.1–42 ng/mL, precision of 0.2–4.1%, and accuracy better than 5%. Furthermore, good agreement between measured and certified values of a National Institute of Standards and Technology certified reference material of wheat flour (SRM 1567a) was found. It was confirmed that the proposed method could be used successfully as an alternative to microwave-assisted acid digestion in routine multielement analyses of wheat crispbreads.

Solubility and bioaccessibility of Ba, Ca, Cr, Cu, Fe, Mg, Mn, P, Sr and Zn in slim coffees were investigated using an in vitro method. Two different compositions of solutions simulating gastric and intestinal juices were tested: SGJ1 + SIJ1 (0.02% pepsin in 0.10 mol L-1 HCl; 0.015% pancreatin with 0.15% bile salts in 0.10 mol L-1 NaHCO3) and SGJ2 + SIJ2 (0.32% pepsin with 0.20% NaCl in 0.08 mol L-1 HCl; 0.40% pancreatin with 2.5% bile salts in 0.10 mol L-1 NaHCO3). Soluble and bioaccessible fractions (in %) in reference to total concentrations of studied elements in infusions were as follows: Ba (81.2, 34.2), Ca (84.4, 44.5), Cr (80.1, 44.8), Cu (69.2, 24.1), Fe (72.5, 6.6), Mg (89.5, 69.6), Mn (44.3, 28.4), P (96.6, 84.6), Sr (85.9, 46.8), Zn (80.8, 59.5). These results suggest that slim coffees are not a rich source of minerals.

A simple and fast method of the analysis of green coffee infusions was developed to measure total concentrations of Ca, Cu, Fe, Mg and Mn by high resolution-continuum source flame atomic absorption spectrometry. The precision of the method was within 1-8%, while the accuracy was within -1% to 2%. The method was used to the analysis of infusions of twelve green coffees of different geographical origin. It was found that Ca and Mg were leached the easiest, i.e., on average 75% and 70%, respectively. As compared to the mug coffee preparation, the rate of the extraction of elements was increased when infusions were prepared using dripper or Turkish coffee preparation methods. Additionally, it was established that the antioxidant activity of green coffee infusions prepared using the mug coffee preparation was high, 75% on average, and positively correlated with the total content of phenolic compounds and the concentration of Ca in the brew.

Various sample preparation procedures, such as common wet digestions and alternatives based on solubilisation in aqua regia or tetramethyl ammonium hydroxide, were compared for the determination of the total Ba, Ca, Cr, Cd, Cu, Fe, Mg, Mn, Ni, P, Pb, Se, Sr and Zn contents in Brazil nuts using inductively coupled plasma optical emission spectrometry (ICP-OES). For measurement of Se, a hydride generation technique was used. The performance of these procedures was measured in terms of precision, accuracy and limits of detection of the elements. It was found that solubilisation in aqua regia gave the best results, i.e. limits of detection from 0.60 to 41.9 ng ml(-1), precision of 1.0-3.9% and accuracy better than 5%. External calibration with simple standard solutions could be applied for the analysis. The proposed procedure is simple, reduces sample handling, and minimises the time and reagent consumption. Thus, this can be a vital alternative to traditional sample treatment approaches based on the total digestion with concentrated reagents. A phenomenon resulting from levels of Ba, Se and Sr in Brazil nuts was also discussed.

The bioaccessibility of Ca, Mg, Mn and Fe in ground coffee brews was assessed through in vitro gastrointestinal digestion with stomach and intestinal juice solutions (pepsin, pancreatin and bile salts). Absorption of metals in the intestinal villi was simulated by ultrafiltration over a 3 kDa molecular weight cut-off semi-permeable membrane. Concentrations of Ca, Fe, Mg and Mn in coffee infusions and permeates of gastrointestinal incubates were measured by flame atomic absorption spectrometry. It was established that Mg, with a 62% contribution to the bioaccessible fraction, was the most bioaccessible. The bioaccessibilities of Ca (42%) and Fe (43%) were similar but individual results for both metals varied widely. The least bioaccessible metal was Mn, with an average contribution of 27%. Drinking one cup of coffee daily covers dietary reference intakes of Ca, Fe, Mg and Mn to a small degree (less than 3%).

A simpler, and faster than wet digestion, sample treatment was proposed prior to determination of total concentrations for selected macro- (Ca, Mg) and microelements (Fe, Mn) in soluble coffees by flame atomic absorption spectrometry. Samples were dissolved in water and acidified with HNO3. Precision was in the range 1-4% and accuracy was better than 2.5%. The method was used in analysis of 18 soluble coffees available on the Polish market. Chemical fractionation patterns for Ca, Fe, Mg and Mn in soluble coffees, as consumed, using a two-column solid-phase extraction method, determined Ca, Mg and Mn were present predominantly as cations (80-93% of total content). This suggests these elements are likely to be highly bioaccessible.