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Accumulation and within-mushroom distribution of elements in red cracking bolete (Xerocomellus chrysenteron) collected over the extended period from compositionally contrasting substrates

Date: 2023
Authors: Andronikov, AV;Andronikova, IE;Sebek, O;Martinkova, E;Stepanova, M;
References: Environmental monitoring and assessment 195 1157
Keywords/Products: Agilent;Concentric;Glass Nebulizer;Meinhard;
We conducted a study of elemental compositions of Xerocomellus chrysenteron samples accompanied by samples of related substrate soils. All samples were collected during the harvesting seasons 2021 and 2022 from three forested sites almost unpolluted by recent human activities and underlain by contrasting bedrock (granite, amphibolite, and serpentinite). Elements such as Ag, Cd, K, P, Rb, S, Se, and Zn were the main elements enriched in the mushroom's fruiting bodies relative to the substrate. Concentrations of most elements in mushrooms were not site-dependent, with only Ag, As, Rb, and Se concentrations significantly depending on the bedrock composition. Some elements analyzed in mushrooms displayed temporal features, but such features were not systematic and varied for each element. Most analyzed elements were distributed unevenly within the mushroom's fruiting bodies, with apical parts generally enriched in mobile elements. Mushrooms influenced concentrations of Ag, Cd, K, and Rb and a few other elements in the substrate via uptake, but such influence was very limited and can be responsible for only 2.5-11.5% of total depletion of the affected substrate in the named elements.

Fractionation of selenium isotopes during biofortification of Saccharomyces cerevisiae and the influence of metabolic labeling with 15N

Date: 2023
Authors: Mejia Diaz, LF;Karasinski, J;Wrobel, K;Corrales Escobosa, AR;Yanez Barrientos, E;Halicz, L;Bulska, E;Wrobel, K;
References: Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry 28 655-667
Keywords/Products: ICP;ICP-MS;Meinhard;
Isotope fractionation of metals/metalloids in biological systems is an emerging research area that demands the application of state-of-the-art analytical chemistry tools and provides data of relevance to life sciences. In this work, Se uptake and Se isotope fractionation were measured during the biofortification of baker's yeast (Saccharomyces cerevisiae)-a product widely used in dietary Se supplementation and in cancer prevention. On the other hand, metabolic labeling with 15N is a valuable tool in mass spectrometry-based comparative proteomics. For Se-yeast, such labeling would facilitate the assessment of Se impact on yeast proteome; however, the question arises whether the presence of 15N in the microorganisms affects Se uptake and its isotope fractionation. To address the above-mentioned aspects, extracellularly reduced and cell-incorporated Se fractions were analyzed by hydride generation-multi-collector inductively coupled plasma-mass spectrometry (HG MC ICP-MS). It was found that extracellularly reduced Se was enriched in light isotopes; for cell-incorporated Se, the change was even more pronounced, which provides new evidence of mass fractionation during biological selenite reduction. In the presence of 15N, a weaker preference for light isotopes was observed in both, extracellular and cell-incorporated Se. Furthermore, a significant increase in Se uptake for 15N compared to 14N biomass was found, with good agreement between hydride generation microwave plasma-atomic emission spectrometry (HG MP-AES) and quadrupole ICP-MS results. Biological effects observed for heavy nitrogen suggest 15N-driven alteration at the proteome level, which facilitated Se access to cells with decreased preference for light isotopes.

Determination of Heavy Metal Content: Arsenic, Cadmium, Mercury, and Lead in Cyano-Phycocyanin Isolated from the Cyanobacterial Biomass

Date: 2023
Authors: Galinyt?, D;Bal?i?nait?-Murzien?, G;Karosien?, J;Morudov, D;Naginien?, R;Baranauskien?, D;Šulinskien?, J;Kudlinskien?, I;Savickas, A;Savickien?, N;
References: Plants (Basel, Switzerland) 12 ~
Keywords/Products: ICP;ICP-MS;Meinhard;sample introduction;
Cyano-phycocyanin (C-PC) is a light-absorbing biliprotein found in cyanobacteria, commonly known as blue-green algae. Due to its antioxidative, anti-inflammatory, and anticancer properties, this protein is a promising substance in medicine and pharmaceuticals. However, cyanobacteria tend to bind heavy metals from the environment, making it necessary to ensure the safety of C-PC for the development of pharmaceutical products, with C-PC isolated from naturally collected cyanobacterial biomass. This study aimed to determine the content of the most toxic heavy metals, arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) in C-PC isolated from different cyanobacterial biomasses collected in the Kaunas Lagoon during 2019-2022, and compare them with the content of heavy metals in C-PC isolated from cultivated Spirulina platensis (S. platensis). Cyanobacteria of Aphanizomenon flos-aquae (A. flos-aquae) dominated the biomass collected in 2019, while the genus Microcystis dominated the biomasses collected in the years 2020 and 2022. Heavy metals were determined using inductively coupled plasma mass spectrometry (ICP-MS). ICP-MS analysis revealed higher levels of the most investigated heavy metals (Pb, Cd, and As) in C-PC isolated from the biomass with the dominant Microcystis spp. compared to C-PC isolated from the biomass with the predominant A. flos-aquae. Meanwhile, C-PC isolated from cultivated S. platensis exhibited lower concentrations of As and Pb than C-PC isolated from naturally collected cyanobacterial biomass.

Partitioning and Speciation of Lanthanides in the Magnetite (Hematite)-Hydrothermal Solution System at 450°C and 100 MPa

Date: 2023
Authors: Smagunov, N;Lipko, S;Tauson, V;Belozerova, O;Babkin, D;
References: Geochemistry International 61 948-955
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;Quartz Nebulizer;sample introduction;
—First results of the experimental study of a hydrothermal multisystem including lanthanides (_Ln_) and Fe oxides (magnetite and hematite) are presented. _Ln_ concentrations in solutions and crystals were determined by ICP-MS and LA-ICP-MS, respectively. The _Ln_ partition and cocrystallization coefficients obtained are interpreted as the maximum estimates of “true” values corresponding to structurally bound admixture. It is shown that _Ln_ (except for Eu) are the compatible elements in hydrothermal magnetite; heavy _Ln_ (beginning with Tb) are compatible in hematite. The pronounced tendency of the increase of both coefficients with increasing _Ln_ atomic number beginning from Gd-Tb was established. This is of great importance when light to heavy Ln ratio is used as a typochemical guide for localization of ore source. The _Ln_-rich phases in association with magnetite and hematite were obtained. These phases have oxychloride (without Fe) and oxyhydroxide (with Fe) composition and exemplify the simultaneous occurrence of light and heavy _Ln_ within a single hydrothermal system due to the co-crystallization of phases selectively accumulating light and heavy lanthanides.

Wall loss of semi-volatile organic compounds in a Teflon bag chamber for the temperature range of 262-298 K

Date: 2023
Authors: He, L;Liu, W;Li, Y;Wang, J;Kuwata, M;Liu, Y;
References: Preprints ~ ~
Keywords/Products: Aerosol;Meinhard;TR-30-A1;
. Teflon bag chambers have long been used for investigating atmospheric chemical processes, including secondary organic aerosol formation. Wall-loss process of gas-phase species in Teflon bag chambers has typically been investigated at around room temperature. Recent laboratory studies started employing Teflon bag chambers at sub-273 K conditions for simulating wintertime and upper tropospheric environments. However, temperature dependence in vapor wall-loss processes of semi-volatile organic compounds (SVOCs) in a Teflon bag chamber has not well been investigated. In this study, we experimentally investigated wall-loss process of C14-C19 n-alkanes in a 1 m3 Teflon bag for the temperature range of 262 to 298 K. Enhanced wall losses of the tested n-alkanes were observed following the decrease in temperature. For instance, 65 % of C14 n-alkane was lost to the wall 15 hours after injection at room temperature, while the corresponding value was 95 % at 262 K. The experimental data were analyzed using the two-layer kinetic model, which considers both absorption of gas phase species to the surface layer of Teflon wall and diffusion to the inner layer. The experimental data demonstrated that absorption of gas phase species by the surface layer enhanced at lower temperature. The temperature dependence in absorption was well accounted using the equilibrium dissolution model of organic compounds to the Teflon surface by considering reduced saturation vapor pressure at lower temperature. On the contrary, diffusion process of n-alkanes from the surface to inner layer slowed down at reduced temperature. Hence the relative importance of the surface and inner layers on wall-loss process changes with temperature. Mechanistic studies on these processes will need to be conducted in the future to quantitatively predict the influence of temperature-dependent wall-loss processes of SVOCs on laboratory experimental results.

Biogeochemistry concepts in medicine: Radiosensitizing pancreatic cancer through pathology driven biosynthesis of gold nanoparticles.

Date: 2023
Authors: Schwartz-Duval, A;Mackeyev, Y;Gagea, M;Krishnan, S;Sokolov, K;
References: Nanoscience ~ ~
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;sample introduction;
An effective strategy for overcoming radiotherapy resistance is to sequester radiosensitizing hafnium oxide or gold nanoparticles (GNPs) within tumors, but desmoplasia, but desmoplasia creates a delivery barrier impeding this approach. Here we report a radiosensitization strategy that overcomes this limitation by applying an atomic-scale agent - ionic gold - for in situ biosynthesis of GNPs within tumors. We showed that the in situ generation of GNPs occurs with higher efficiency in cancerous pancreatic cells than in non-cancerous cells and that these GNPs have high nuclear localization, resulting in the specific radiosensitization of cancer cells. Our studies in a xenograft murine model of pancreatic cancer revealed a uniform distribution of GNPs in the tumor, with insignificant gold content and low toxicity in normal organs. Radiosensitization by biosynthesized GNPs halted tumor growth for more than 30 days and was associated with a significantly higher median survival versus radiation alone (235 vs 102 days, respectively).

Sp-ICP-MS and HR-CS-GFAAS as Useful Available Techniques for the Size Characterization and Speciation of Ionic and Nanoparticular Zinc in Cosmetic and Pharmaceutical Samples

Date: 2023
Authors: García-Mesa, J;Morales-Benítez, I;Montoro-Leal, P;Lopez Guerrero, M;Vereda Alonso, E;
References: Available at SSRN  ~ ~
Keywords/Products: Glass Nebulizer;ICP;ICP-MS;Meinhard;Type C;
Abstract Unavailable

Phase Transformations from a Local Structure Perspective

Date: 2023
Authors: Wilson, CE;
References: Thesis ~ ~
Keywords/Products: Concentric;Glass Nebulizer;Meinhard;Optima;Perkin Elmer;POINT;
Phase transformations are commonly exploited in materials science for a multitude of technologies due to a coinciding property transition. However, the understanding of solid-solid phase transformations is still developing, especially from a local perspective (< 30 Å). A suite of characterization and analysis techniques both proceeding and preceding the phase and property transition provides structural information starting at two angstroms. Operando and in situ experimental methodologies have advanced to the point that these structural phase transformations can be observed throughout the entire transition. The development of these advanced experimental characterization techniques with respect to x-ray diffraction, and total x-ray scattering along with large dataset analysis methodologies elucidated highly detailed local structure information. An archetypal first-order metal-insulator transition (MIT) material, vanadium dioxide, was first investigated using these techniques which were then extended to the battery cathode material, titanium trisulfide. From these analyses, the Peierls-Mott hypothesis of MIT origin was supported and local vanadium oxidation upon increasing tungsten-substitution was found to instigate a decrease in the change in properties across the transition temperature. For titanium trisulfide, it was found that kinetically driven Li-entrapment is decreasing the overall gravimetric capacity retention leading to premature battery death.

Given the high intake of potatoes by the world population, reliable methodologies with very low limits of detection are needed for the determination of highly toxic elements such as arsenic. For that purpose, graphite furnace atomic absorption spectrometry could be considered one of the techniques of choice; notwithstanding the matrix effect prevented its application in arsenic determination in potatoes as the analytical signal was absolutely depleted. The potential interferent was searched among the mineral content. As a result, it was found that the interference presumably could be attributed to phosphate. Attempts to overcome the matrix interference by different sample digestion methodologies, chemical modification and temperature variation in the graphite furnace ashing and ashing / atomization stage respectively, were unsuccessful. Consequently, an alternative methodology for determining arsenic in potatoes using hydride generation microwave induced plasma optical emission spectrometry was developed. Limit of detection was 0.0030 mg kg-1 in fresh potatoes. The developed method is a robust, simple and low cost alternative for total arsenic safe monitoring of this highly consumed worldwide vegetable.

Date: 2023
Authors: Zambra, R;Sixto, A;Pistón, M;Mollo, A;
References: Brazilian Journal of Analytical Chemistry ~ ~
Keywords/Products: Meinhard;
Given the high intake of potatoes by the world population, reliable methodologies with very low limits of detection are needed for the determination of highly toxic elements such as arsenic. For that purpose, graphite furnace atomic absorption spectrometry could be considered one of the techniques of choice; notwithstanding the matrix effect prevented its application in arsenic determination in potatoes as the analytical signal was absolutely depleted. The potential interferent was searched among the mineral content. As a result, it was found that the interference presumably could be attributed to phosphate. Attempts to overcome the matrix interference by different sample digestion methodologies, chemical modification and temperature variation in the graphite furnace ashing and ashing / atomization stage respectively, were unsuccessful. Consequently, an alternative methodology for determining arsenic in potatoes using hydride generation microwave induced plasma optical emission spectrometry was developed. Limit of detection was 0.0030 mg kg-1 in fresh potatoes. The developed method is a robust, simple and low cost alternative for total arsenic safe monitoring of this highly consumed worldwide vegetable.

Prep Signal

Date: 2023
Authors: Sartor, S;Toaldo, IM;Panceri, CP;Caliari, V;Luna, AS;Bordignon-Luiz, JS;
References: ~ ~
Keywords/Products: Meinhard;
The identification and quantification of individual polyphenolics in wine samples throughout the aging process were performed by high performance liquid chromatography with diode array detection (HPLC-DAD) (Shimadzu, Kyoto, Japan). For all polyphenolic compounds, analyte separation was achieved on a Shim-pack CLC-ODS end-capped reverse phase-column (4.6 x 250 mm, 5 µm) from Shimadzu. For the analysis, 20 ?L of samples were injected into the HPLC system. Sixteen phenolic compounds belonging to the subclasses of hydroxybenzoic acids, hydroxycinnamic acids, flavonols, flavan-3-ols, tyrosol and stilbenes were quantified in wine samples and their levels were monitored up to 12 months of over-lees aging. Sample preparation and HPLC analysis were performed according to Burin, Ferreira-Lima, Panceri, & Bordignon-Luiz (2014). In the procedure, wine samples were submitted to liquid-liquid extraction prior to injection into the chromatography system. The mobile phase A was water: acetic acid (98:2 v/v) and mobile phase B was water: acetonitrile: acetic acid (58:40:2 v/v/v). The gradient elution was as follows: 0-80 % solvent B for 55 min, 80-100 % B for 15 min and 100-0 % B for 5 min, with the flow rate set at 0.9 mL min-1 and total run time of 75 min. The detection was set at 280 mn for tyrosol, catechin and epicatechin, at 320 nm for caffeic, trans-caftaric, p-coumaric and ferulic acids, at 360 nm for myricetin, quercetin and kaempferol, and at 306 nm for trans- resveratrol. The separation of hydroxybenzoic acids (gallic, protocatechuic, syringic, vanillic and ellagic) was carried out using a binary mobile phase consisted of ultrapure water: acetic acid (98:2, v/v) (A) and acetonitrile: solvent A (80:20, v/v) (B). The elution gradient was as follows: 0-35 % B for 35 min, 35-0 % B for 3 min, with total run time of 38 min. The flow rate was 1.0 mL min-1 and the detection was set at 280 nm for all the compounds, with the exception of ellagic acid that was detected at 254 nm. The 3-O-monoglucoside anthocyanins (malvidin, cyanidin, delphinidin and peonidin) were determined according to Revilla, Pérez-Magariño, González-Sanjosé, & Beltrán (1999). A gradient elution programme was used with the mobile phase consisted of water: formic acid (90:10 v/v) (A) and water: methanol: formic acid (45:45:10 v/v/v) (B) as follows: 35-95 % solvent B for 20 min, 95-100 % solvent B for 5 min, 100-35 % solvent B for 5 min, with this maintained for 5 min for a total run time of 35 min. The flow rate was kept at 0.8 mL min-1 and the detection set at 520 nm.

Production and catalytic upgrading of 2,3-butanediol fermentation broth into sustainable aviation fuel blendstock and fuel properties measurement

Date: 2023
Authors: Affandy, M;Zhu, C;Swita, M;Hofstad, B;Cronin, D;Elander, R;Lebarbier Dagle, V;
References: Fuel 333 126328
Keywords/Products: Meinhard;POINT;
With the increasing demand for sustainable supplies of aviation fuel and need to address climate change, new conversion technologies are needed to efficiently process biomass, produce high quality jet fuel blendstock, and meet carbon emission targets. This study demonstrates the synthesis, conditioning, and catalytic upgrading of 2,3-butanediol (BDO) fermentation broth into a jet fuel blendstock candidate. A high-titer 2,3-BDO fermentation broth (i.e., ?90 g/L) was produced at a 100-L scale and pretreated via nanofiltration to decrease the impurities level in the broth from 4.6 to 0.6 wt%. A novel process for catalytic upgrading of aqueous 2,3-BDO into a jet fuel blendstock candidate was developed, and each step was efficiently demonstrated. The catalytic steps include 1) 2,3-BDO dehydration into methyl ethyl ketone (MEK) over AlPO4, 2) MEK conversion into olefins over Zn1Zr10Ox, 3) oligomerization of olefins over a zeolite beta, and 4) hydrogenation over platinum/carbon. Both the model feed and real 2,3-BDO fermentation broth were tested for upgrading 2,3-BDO to MEK. With the real feed, a continuous loss of conversion (i.e., >50 % loss over ?140 h time-on-stream [TOS]) was partly attributed to reversible deactivation from coking species. However, the conversion remained stable with the model feed, which demonstrates the efficiency of the first step for converting aqueous 2,3-BDO (10 wt% in water). For upgrading MEK to olefins, high selectivity to olefins (i.e., 82.5 %) was obtained at high conversion levels (i.e., 93-98 %) with stable conditions being achieved for > 70-hours TOS. Oligomerization of light olefins, which was demonstrated for > 270 h TOS, mainly led to the formation of dimers (C8-10) and trimers (C13-14). The oligomerized product was hydrogenated and distilled to recover the jet fraction (35 mass% or 40.9 % carbon based yield), which consists mostly of desired isoalkanes (31.7 wt%), n-alkanes (24.5 wt%), and cycloalkanes (29.6 wt%). While some improvement is still needed to meet ASTM D7566 specifications for viscosity and final boiling point temperature, freezing point, density, aromatics content, and sulfur content of the jet blendstock candidate were within acceptable ranges, thus highlighting the potential of this process for production of jet fuel blendstock.

Arsenic speciation in canned tuna fish samples (Thunnus) using ionic chromatography inductively coupled plasma mass spectrometry

Date: 2023
Authors: Hoyne, T;Vieira, L;Heringer, O;Brandão, G;Souza, J;Carneiro, M;
References: Journal of Food Composition and Analysis 116 105051
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;
Arsenic speciation analysis was conducted on in oil and in brine canned solid tuna samples using ionic chromatography inductively coupled plasma mass spectrometry (IC-ICP-MS). First, the method was optimized and validated. The extraction of water-soluble arsenic species (arsenobetaine (AsB), dimethylarsinic acid (DMA), monomethylarsonic acid (MMA), As (III), and As (V)) was performed with (NH4)2CO3 at pH 10.5. The presence of the sample matrix showed no effect on the selectivity of the method by a t-test (p < 0.05) and an external calibration method was applied. The limits of quantification for the five arsenic species were 0.59 mg kg?1 (AsB), 0.10 mg kg?1 (DMA), 0.12 mg kg?1 (As (III)), 0.07 mg kg?1 (MMA) and 0.10 mg kg?1 (As (V)). Method accuracy was tested through the analysis of the reference material BCR-627 (tuna fish muscle tissue) and a good agreement was obtained. Total arsenic in the solid canned tuna ranged from 2.65 to 5.81 mg kg?1 in-oil samples and from 2.74 to 5.70 mg kg?1 in the in-brine samples, levels higher than the limits established by the Brazilian sanitary standards. However, the speciation showed that the major species is the non-toxic arsenobetaine.

Species- and Metal-Specific Responses of the Ionome of Three Duckweed Species under Chromate and Nickel Treatments

Date: 2023
Authors: Oláh, V;Irfan, M;Szabó, Z;Sajtos, Z;Ragyák, Á;Döncz?, B;Jansen, M;Szabó, S;Mészáros, I;
References: Plants 12 180
Keywords/Products: Agilent;ICP;ICP-OES;Meinhard;
In this study, growth and ionomic responses of three duckweed species were analyzed, namely Lemna minor, Landoltia punctata, and Spirodela polyrhiza, were exposed for short-term periods to hexavalent chromium or nickel under laboratory conditions. It was found that different duckweed species had distinct ionomic patterns that can change considerably due to metal treatments. The results also show that, because of the stress-induced increase in leaf mass-to-area ratio, the studied species showed different order of metal uptake efficiency if plant area was used as unit of reference instead of the traditional dry weight-based approach. Furthermore, this study revealed that ?XRF is applicable in mapping elemental distributions in duckweed fronds. By using this method, we found that within-frond and within-colony compartmentation of metallic ions were strongly metal- and in part species-specific. Analysis of duckweed ionomics is a valuable approach in exploring factors that affect bioaccumulation of trace pollutants by these plants. Apart from remediating industrial effluents, this aspect will gain relevance in food and feed safety when duckweed biomass is produced for nutritional purposes.

Image-Guided Nanodelivery of Pt(IV) Prodrugs to GRP-Receptor Positive Tumors

Date: 2023
Authors: Silva, F;Mendes, C;D'Onofrio, A;Campello, MPC;Marques, F;Pinheiro, T;Gonçalves, K;Figueiredo, S;Gano, L;Ravera, M;Gabano, E;Paulo, A;
References: Nanotheranostics 7 22-40
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-MS;Meinhard;PC3;Thermo;
Over the last decades, gold nanoparticles (AuNPs) have proven to be remarkable tools for drug delivery and theranostic applications in cancer treatment. On the other hand, Pt(IV) prodrugs have been employed as an interesting alternative to the more common Pt(II) complexes, such as cisplatin, for cancer chemotherapy. Searching to design an image-guided nanocarrier to deliver selectively Pt(IV) prodrugs to tumors expressing the gastrin releasing peptide receptor (GRPR), we have synthesized small core AuNPs carrying a thiolated DOTA derivative, a GRPR-targeting bombesin analog (BBN[7-14]) and a Pt(IV) prodrug attached to the AuNPs without (AuNP-BBN-Pt1) or with a PEGylated linker (AuNP-BBN-Pt2 and AuNP-BBN-Pt3). In the GRPR+ prostate cancer PC3 cell line, the cytotoxic activity of the designed AuNP-BBN-Pt nanoparticles is strongly influenced by the presence of the PEGylated linker. Thus, AuNP-BBN-Pt1 displayed the lowest IC50 value (9.3 ± 2.3 µM of Pt), which is comparable to that exhibited by cisplatin in the same cell line. In contrast, AuNP-BBN-Pt1 showed an IC50 value of 97 ± 18 µM of Pt in the non-tumoral RWPE-1 prostate cells with a much higher selective index (SI) towards PC3 cells (SI = 10) when compared with cisplatin (SI = 1.3). The AuNPs were also successfully labeled with 67Ga and the resulting 67Ga-AuNP-BBN-Pt were used to assess their cellular uptake in PC3 cells, with AuNP-BBN-Pt1 also displaying the highest cellular internalization. Finally, intratumoral administration of 67Ga-AuNP-BBN-Pt1 in a PC3 tumor-bearing mice showed a prolonged retention of the nanoparticle compared to that of cisplatin, with optimal in vivo stability and 20% of the injected platinum remaining in the tumor after 72 h post-injection. Furthermore, microSPECT imaging studies confirmed the uptake and considerable retention of the 67Ga-labeled AuNPs in the tumors. Overall, these results show the potential of these targeted AuNPs loaded with Pt(IV) prodrugs for prostate cancer theranostics.

Smelter-derived soil contamination in Luanshya, Zambia

Date: 2023
Authors: Baieta, R;Ettler, V;Van?k, A;Drahota, P;K?íbek, B;Nyambe, I;Mihaljevi?, M;
References: The Science of the total environment 867 161405
Keywords/Products: Meinhard;
Extensive mining and smelting contributed to the declining quality of Luanshya soils. The local smelter was the epicenter of contamination as shown by a spatial distribution analysis. Closeby soil profiles smelter exhibit extremely high Cu concentrations (up to 46,000 mg kg-1 Cu) relative to deeper layers where only background levels of trace elements were observed. A remote profile did not exhibit significant contamination. Lead isotopic ratios revealed that Pb contamination in the Luanshya soils was not smelter-derived. It was shown in this way that the historical usage of leaded gasoline was the main source of this metal. Although the Luanshya smelter also produced Co, this metal was not an important contaminant. Copper leaching was a concern in Luanshya. Upwards of 52 % of Cu was extractable in the exchangeable step of a sequential extraction procedure (SEP), but only for samples where Cu concentrations were high, suggesting that Cu was released exclusively from anthropogenic particles. This was supported by the SEP results for similar depths at the remote soil, where only a small fraction of Cu was labile (5.6 %). Lead and Co were strongly bound in the soils throughout. The excess of Cu in the topsoils was mostly bound in smelter-derived particles. These appeared as spherical fast-cooled droplets composed mostly of sulfides, oxides, and glass. X-ray diffraction and electron probe microanalysis of those particles allowed for a phase classification. Compositions were regularly not stoichiometric so most particles were classified as intermediate solid solutions. However, molecular proportions often closely resembled those of bornite, chalcanthite, cuprospinel, covellite, delafossite, diginite, or hydrous ferric oxides. Concentrations of Cu were often 100 % near the center of the particles indicating an inefficient smelting process. Weathering to some degree was common, which in conjunction with the susceptibility of Cu leaching was highly alarming.

Environmental exposure to cadmium in breast cancer - association with the Warburg effect and sensitivity to tamoxifen

Date: 2023
Authors: Tarhonska, K;Janasik, B;Roszak, J;Kowalczyk, K;Lesicka, M;Reszka, E;Wieczorek, E;Braun, M;Kolacinska-Wow, A;Skokowski, J;Kalinowski, L;Jablonska, E;
References: Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 161 114435
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;Quartz Nebulizer;
The association between cadmium and breast cancer remains unexplained due to inconsistent epidemiological data and unknown underlying mechanisms. This study aimed to assess the relationship between environmental exposure to cadmium and the Warburg effect in breast cancer and, thus, its possible interference with breast cancer treatment. The observational study in two groups of breast cancer patients indicated a positive correlation between urinary cadmium concentration and tumor expression of HIF1A (a master regulator of the Warburg effect). Further explanatory research in MCF-7 cells showed no impact of cadmium exposure on molecular and biochemical markers of the Warburg effect. However, long-term exposure to a low and environmentally relevant concentration of cadmium led to the accumulation of the metal in MCF-7 cells and decreased their sensitivity to tamoxifen. To conclude, the association between cadmium and the Warburg effect was suggested in the observational study, although not confirmed in vitro. Nevertheless, cadmium seems to interfere with tamoxifen treatment which deserves further investigation in terms of its possible implication in intrinsic resistance to hormone therapy.

High temperature total consumption sample introduction system coupled to microwave plasma optical emission spectrometry (MIP-OES) for the analysis of aqueous samples

Date: 2023
Authors: Martínez, S;Sánchez, R;Todolí, JL;
References: Analytica chimica acta 1249 340948
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICP-OES;Meinhard;sample introduction;TR-30-A1;
The high temperature torch integrated sample introduction system (hTISIS) is coupled to microwave plasma optical emission spectrometry (MIP-OES) for the first time. The goal of this work is to develop an accurate analysis of digested samples under continuous sample aspiration mode by coupling the hTISIS to a MIP-OES instrument. To achieve this, different operating conditions such as, nebulization flow rate, liquid flow rate and the spray chamber temperature were optimized in terms of sensitivity, limits of quantification (LOQs) and background equivalent concentration (BECs) for the determination of Ca, Cr, Cu Fe, K, Mg, Mn, Na, Pb and Zn, and these values were compared with those reported with a conventional sample introduction system. Under optimum conditions (0.8-1 L min-1, 100 ?L min-1 and 400 ?C, respectively), the hTISIS improved MIP-OES analytical figures of merit and shortened 4-times wash out times with respect to a conventional cyclonic spray chamber, reporting an enhancement factor in the sensitivity among 2-47 times and LOQs from 0.9 to 360 ?g kg-1. Once the best operating conditions were set, the magnitude of the interference caused by 15 different acid matrices (2, 5 and 10% w/w of HNO3, H2SO4, HCl and mixtures of HNO3 with H2SO4 and HNO3 with HCl) was significantly lower for the former device. Finally, 6 different digested oily samples (used cooking oil, animal fat, corn oil and the same samples after a filtration step) were analyzed by means of an external calibration approach based on the use of multielemental standards prepared in 3% (w/w) HCl solution. The obtained results were compared against those supplied by a conventional methodology employing an inductively coupled plasma optical emission spectrometry, ICP-OES, instrument. It was clearly concluded that the hTISIS coupled to MIP-OES afforded similar concentrations as compared to the conventional methodology.

The Toxicological Analysis and Toxicological Risk Assessment of Chosen Elemental Impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) in Green Tea (Camellia sinensis (L.)) Infusions

Date: 2023
Authors: Frydrych, A;Noga, M;Milan, J;Kondratowicz-Pietruszka, E;Kro?niak, M;Jurowski, K;
References: Nutrients 15 ~
Keywords/Products: ICP;ICP-MS;Meinhard;
Our study's objective is to evaluate the potential health effects of elemental impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) found in green tea infusions (Camellia sinensis (L.)). The ICP-MS-based methodology was employed for elemental analysis and a detailed health risk evaluation based on weekly consumption (?g/L of infusion/week). The provisional tolerable weekly intake (PTWI), established by the Joint FAO Expert Committee on infusion/week/month based on existing literature data, was then compared to the subjects with data from the available literature. The exposure of the study items to Co ranged from 0.07904 to 0.85421 ?g/day. On the contrary, the ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) guidelines state that the established permitted daily exposure PDE (oral exposure) for Co is 50 ?g/day. The PDE of lithium is around 560 ?g/day, and according to our study, the estimated daily exposure of the evaluated products to Li fell between 0.0185 and 0.7170 ?g/day. Our research also revealed modest concentrations of Cs (0.399-2.654 ?g/L), Mo (0.0113-0.107 ?g/L), and Sr (9.848-22.331 ?g/L) in infusions. The recognized PDE for molybdenum is approximately 3400 ?g/day. Only two samples contained silver, and when considering daily consumption, the predicted daily exposure to Ag is between 4.4994 and 0.03122 ?g/day. The amounts of all evaluated elements in a daily dose of green tea infusions should not harm the consumer's health. Further considerations should take aspects, such as constant change and environmental pollution, into account.

Cerebral iron deficiency may induce depression through downregulation of the hippocampal glucocorticoid-glucocorticoid receptor signaling pathway

Date: 2023
Authors: Zhang, H;He, L;Li, S;Zhai, M;Ma, S;Jin, G;Li, M;Zhou, F;Tian, H;Nuerkaman, T;Sun, Q;Zhang, Y;Hou, J;Sun, G;Yin, S;
References: Journal of affective disorders ~ ~
Keywords/Products: Agilent;ICP;ICP-MS;Meinhard;
Iron is a trace essential element to sustain the normal neurological function of human. Many researches had reported the involvement of iron deficiency (ID) in neural development and cognitive functions. However, the role of ID in pathogenesis of depression and its underlying mechanism are still unclear.In this study, we first used chronic unpredicted mild stress (CUMS) and iron deprivation mouse models to clarify the pathogenesis role of cerebral ID in depression. Then the role of hippocampal glucocorticoid (GC)-glucocorticoid receptor (GR) pathway in cerebral ID induced depression were elucidated in iron deprivation mice and iron deficiency anemia patients.Our results revealed that both CUMS and iron deprivation could induce cerebral ID in mice, and combination of iron deprivation and CUMS could accelerate the onset and aggravate the symptoms of depression in mice. In hippocampus, ID led to neuronal injury and neurogenesis decrease, which might be related to downregulation of GC-GR signaling pathway caused GR dysfunction, thereby inhibiting the negative feedback regulation function of hippocampus on hypothalamic-pituitary-adrenal (HPA) axis. Moreover, the overactivity of HPA axis in iron deprivation mice and iron deficiency anemia patients also confirmed GR dysfunction.Iron deprivation led to food and water intake decrease of mice, which may affect the behavioral test. In addition, we mainly evaluated the role of hippocampal ID in depression, and the number of iron deficiency anemia patients was limited.Our results identified that cerebral iron homeostasis was a key factor for maintaining mental stability.

Optimization of fermentation parameters for the production of a novel selenium enriched mulberry (Morus nigra) wine

Date: 2023
Authors: Johnson, N;Ekumah, J;Ma, Y;Akpabli-Tsigbe, N;Adade, S;Manching, X;Quaisie, J;Kwaw, E;Wang, C;
References: LWT 178 114608
Keywords/Products: ICP;ICP-MS;Meinhard;
Novel selenium (Se) access media such as wine is increasingly being improved to ease Se access and consumption. Thus, our work intended to enhance mulberry wine as a Se access medium by optimizing wine fermentation conditions using Box-Behnken design (BBD) and Response Surface Methodology (RSM). The approach combined four parameters selected from a factor screening study. Optimizing the parameters, the design predicted the best temperature as 25.01 °C, pH 4.22, °Brix 25 °Bx, and Se 299.99 ?g at a desirability of 0.939. Using these conditions, an optimized Se-enriched mulberry wine (OpSeMW) with a 9.41% alcohol by volume, 695.36 mg/100 mL total polyphenol content, and a total residual Se of 201.58 ?g was attained. It also exhibited improved characteristics regarding its physicochemical properties, color, phytochemical content, antioxidant activity, and microbiological quality compared to ordinary mulberry wine (OMW). Therefore, the optimization technique contributed to producing a Se-enriched mulberry wine as a ready-to-drink beverage to consider in achieving the Se recommended daily allowance. The optimized parameters will also serve as the benchmark for Se-enriched mulberry wine technology development and production scale-up.