Natural Deep Eutectic Solvents as a Key Metal Extractant for Fractionation in Speciation Analysis

The research aimed to use natural deep eutectic solvents (NADES) as an extractant for fractionation of compounds of selected elements from young barley and to compare it with the fractionation of elements from certified element materials. The use of such a comparison made it possible to prove the possibility of extracting the same forms of elements (species) from different materials, which confirmed the option of using NADES as extractants in speciation analysis. The research was conducted with hyphenated techniques—separation by high-performance chromatography coupled to an isotope-specific detector, mass spectrometry (MS) with ionization in inductively coupled plasma (ICP)—which are widely used in speciation analysis. Natural deep eutectic solvents also help introduce Green Analytical Chemistry principles (GAC). According to the results of our studies, the use of different NADES permit the extraction of various metals from a single sample. Moreover, using other natural solvents of eutectic properties helps extract different species of a given metal

Speciation of Arsenic(III) and Arsenic(V) in Plant-Based Drinks

Recently, food products based only on plants have become increasingly popular and are often found on store shelves. It is a specific market response to the growing demand for, and interest in, plant foods. Cow’s milk has also gained its counterpart in the form of plant-based beverages, based on cereals, nuts or legumes. The emergence of an increasingly wide range of plant-based food products has also led to increased research on safe plant food consumption. This study was conducted to quantify total arsenic content and its species (arsenic(III) and (V)) in samples of plant-based beverages purchased at Polish markets. Speciation analysis of arsenic was performed by high-performance liquid chromatography combined with inductively coupled plasma mass spectrometry. The presented study was conducted on six selected plant-based beverages, including almond, millet, soybean, rice, coconut and oat. An analysis using size exclusion chromatography was performed. In order to initially visualize the content of the observed elements and the particle size of the compounds in which they occur, at first the samples were subjected to the size-exclusion chromatography. Speciation analysis of arsenic was carried out using anion-exchange liquid chromatography, combined with inductively coupled plasma mass spectrometry. The presented method was validated with certified reference material (CRM rice flour)

Natural Deep Eutectic Solvents as a Key Metal Extractant for Fractionation in Speciation Analysis

The research aimed to use natural deep eutectic solvents (NADES) as an extractant for fractionation of compounds of selected elements from young barley and to compare it with the fractionation of elements from certified element materials. The use of such a comparison made it possible to prove the possibility of extracting the same forms of elements (species) from different materials, which confirmed the option of using NADES as extractants in speciation analysis. The research was conducted with hyphenated techniques—separation by high-performance chromatography coupled to an isotope-specific detector, mass spectrometry (MS) with ionization in inductively coupled plasma (ICP)—which are widely used in speciation analysis. Natural deep eutectic solvents also help introduce Green Analytical Chemistry principles (GAC). According to the results of our studies, the use of different NADES permit the extraction of various metals from a single sample. Moreover, using other natural solvents of eutectic properties helps extract different species of a given metal

Nanoscale Ion-Exchange Materials: From Analytical Chemistry to Industrial and Biomedical Applications

Nano-sized ion exchangers (NIEs) combine the properties of common bulk ion-exchange polymers with the unique advantages of downsizing into nanoparticulate matter. In particular, being by nature milti-charged ions exchangers, NIEs possess high reactivity and stability in suspensions. This brief review provides an introduction to the emerging landscape of various NIE materials and summarizes their actual and potential applications. Special attention is paid to the different methods of NIE fabrication and studying their ion-exchange behavior. Critically discussed are different examples of using NIEs in chemical analysis, e.g., as solid-phase extraction materials, ion chromatography separating phases, modifiers for capillary electrophoresis, etc., and in industry (fuel cells, catalysis, water softening). Also brought into focus is the potential of NIEs for controlled drug and contrast agent delivery

Uptake, translocation, size characterization and localization of cerium oxide nanoparticles in radish (Raphanus sativus L.)

International audienceDue to their unique physical and chemical properties, the production and use of cerium oxide nanoparticles (CeO 2 NPs) in different areas, especially in automotive industry, is rapidly increasing, causing their presence in the environment. Released CeO 2 NPs can undergo different transformations and interact with the soil and hence with plants, providing a potential pathway for human exposure and leading to serious concerns about their impact on the ecosystem and human organism. This study investigates the uptake, bioaccumulation, possible translocation and localization of CeO 2 NPs in a model plant (Raphanus sativus L.), whose edible part is in direct contact with the soil where contamination is more likely to happen. The stability of CeO 2 NPs in plant growth medium as well as after applying a standard enzymatic digestion procedure was tested by single particle ICP-MS (SP-ICP-MS) showing that CeO 2 NPs can remain intact after enzymatic digestion; however, an agglomeration process was observed in the growth medium already after one day of cultivation. An enzymatic digestion method was next used in order to extract intact nanoparticles from the tissues of plants cultivated from the stage of seeds, followed by size characterization by SP-ICP-MS. The results obtained by SP-ICP-MS showed a narrower size distribution in the case of roots suggesting preferential uptake of smaller nanoparticles which led to the conclusion that plants do not take up the CeO 2 NPs agglomerates present in the medium. However, nanoparticles at higher diameters were observed after analysis of leaves plus stems. Additionally, a small degree of dissolution was observed in the case of roots. Finally, after CeO 2 NPs treatment of adult plants, the spatial distribution of intact CeO 2 NPs in the radish roots was studied by laser ablation ICP-MS (LA-ICP-MS) and the ability of NPs to enter and be accumulated in root tissues was confirmed

Elucidation of the fate of zinc in model plants using single particle ICP-MS and ESI tandem MS

International audienceIn recent years, the increasing use of zinc oxide nanoparticles (ZnO NPs) in many consumer products and industrial applications made them a new potential source of zinc in the environment. After their release into the environment, ZnO NPs can undergo different transformations which are still poorly understood and may influence their potential toxicity. This study investigates for the first time the fate of zinc, supplied in the form of ZnO NPs and ZnCl2, taken up by a model edible plant (lettuce, Lactuca sativa L.) by means of different mass spectrometry techniques. Single particle inductively coupled plasma mass spectrometry (SP-ICP-MS) analysis showed the rapid dissolution of ZnO NPs in the growth medium used for cultivation of lettuce, confirming that only dissolved zinc, not intact NPs, is taken up by plants. Taking into account that the beneficial or toxic effects of zinc depend on its form accumulated by plants, it is crucial to identify the chemical forms of zinc and their distribution in edible plant tissues. Therefore, the second part of this work was focused on the study of zinc speciation in plants cultivated with ZnCl2 by using hyphenated techniques. The proposed approach based on two-dimensional chromatographic (size exclusion – SEC and hydrophilic interaction – HILIC) separation with parallel ICP-MS and ESI-qTOF-MS/ESI-FT-Orbitrap-MS detection allows the determination and identification of minor zinc complexes at environmentally relevant concentrations. Nicotianamine (NA) is shown to be the major ligand binding zinc in lettuce leaves, and the Zn–NA complex is responsible for more than 70% of the total zinc content extracted from lettuce leaves by means of ammonium acetate buffer

Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate

The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic enzymes, which ensured liberation of selenium species contained in peptides or proteins. Separate extractions using an aqueous solution of enzyme-deactivating hydroxylamine hydrochloride counteracted the possible degradation of labile selenium species by enzymes (such as alliinase) that occur naturally in garlic. The selenium content in garlic, which was analysed by ICP¿MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 ¿g g¿1 (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP¿MS detection showed that ¿-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few percent of the total chromatographed selenium in all garlic samples. Se-allyl-selenocysteine and Se-propyl-selenocysteine, which are selenium analogues of biologically active sulfur-containing amino acids known to occur in garlic, were searched for but not detected in any of the extracts. The amendment of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of ¿-glutamyl-Se-methyl-selenocysteine and ¿-glutamyl-Se-methyl-selenomethionine in isolated chromatographic fractions by quadrupole time-of-flight mass spectrometr