Scientific Literature

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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.

Erratum to “Fast determination of trace metals in edible oils and fats by inductively coupled plasma mass spectrometry and ultrasonic acidic extraction” [Journal of Trace Elements and Minerals 1C (2022) 100003]

Date: 2022
Authors: de Souza, R;Toloza, C;Aucélio, R;
References: Journal of Trace Elements and Minerals 2 100011
Keywords/Products: ICP;ICP-MS;Meinhard;sample introduction;
Background: Trace elements play an important role in humans as some are essential for the proper functioning of the body while others may have negative impact in health. Inductively coupled plasma mass spectrometry (ICP-MS) has been used for the determination of nine elements (Cd, Cr, Cu, Fe, Mn, Ni, Ti, V e Zn) in olive oil, soy oil and margarine. Materials and methods: Samples were treated with nitric acid solution (10 % v/v) and heated at 50 0C for 30 min. This mixture was placed in an ultrasonic bath for 20 min, in order to obtain quantitative extraction of trace-elements into the acid solution, which was directly aspirated into the ICP-MS to be quantified, using analytical curves constructed with aqueous standards. Results: The simple sample preparation procedure along with an efficient sample introduction strategy (using a Meinhard K3 nebulizer and a twister cyclonic spray chamber) facilitated the overall analytical process. Internal standardization with Rh was used to correct matrix effects and signal fluctuations. Limits of detection in the ng g-1 range were achieved for all elements and were appropriate for the intended application. The method was tested by the analysis of samples before and after fortification with metalo-organic standards and recoveries between 88 and 117% were achieved. Conclusion: The method was found to lead to reliable results using a fast and simple procedure.

Potential role of acid mine drainage management towards achieving sustainable development in the Johannesburg region, South Africa

Date: 2022
Authors: Abiye, T;Ali, K;
References: Groundwater for Sustainable Development 19 100839
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;TDS;
Acid mine drainage has always been considered to be toxic to the environment. This paper highlights its potential role from a water resource perspective in alleviating water supply issues in the Witwatersrand gold mining region of South Africa. Relevant local and international literature on acid mine drainage (AMD) occurrence and treatment technologies were reviewed and supplemented with additional water quality data from AMD and geochemical data from tailings dams. This study revealed that the tailings dams contain high concentrations of toxic metals (Co, Pb, Cu, U, As, Fe) and oxides such as SiO2, Al2O3, Fe2O3 and FeO. AMD is characterized by acidic pH (1.89-3.50), high ORP (+485 mV to +650 mV), high EC (7475 ?S/cm to 9750 ?S/cm) and brackish TDS (6000 mg/L to 8890 mg/L). The discharge volume of acid mine drainage in the area is approximately 202 million L/day, which can be available to supply water for the community after treatment. This resource can also be fully utilized for extracting minerals, chemicals as well as clean water that are beneficial to support the sustainable development of the region. This may be achieved through the application of reverse osmosis that can produce safe drinking water and associated byproducts (metals, gypsum, iron compounds, acid), as well as neutralization and cation exchange methods to generate water for agricultural uses. The extraction of the minerals also has economic benefits and can contribute to job creation that limits the displacement of the local people in the mining region.

The effects of culinary processing on lithium from lithiated and reference button mushrooms (Agaricus bisporus)

Date: 2022
Authors: Pankavec, S;Falandysz, J;Han?, A;Fernandes, A;
References: Food Chemistry Advances 1 100106
Keywords/Products: Concentric;Concentric nebulizer;Meinhard;
Lithiated products such as button mushrooms that are cultivated in substrates fortified with lithium (Li) salts, have the potential to provide accessible and safe Li dosing as a treatment for some neurological disorders. However, Li losses sustained during culinary processing are not known. This study of commonly used culinary treatments including various combinations of drying, maceration, blanching (of fresh, deep-frozen and re-hydrated mushrooms) and pickling (of fresh and deep-frozen mushrooms) shows that Li is lost from the edible flesh at varying rates depending on the treatment. Blanching of fresh lithiated mushrooms resulted in a 40% loss, increasing to 77-87% when blanching was followed by pickling. Corresponding losses were similar (47-72%) for non-lithiated mushrooms. Higher losses through the combined treatment relative to just blanching appear to be due to chelating and acidifying effects of the vinegar used. This finding has important dose implications for potential future use of lithiated products.

Detection of metals/metalloids and development of engineered plants to fight stress

Date: 2022
Authors: Ahmad, S;Nawaz, M;Zafar, Z;Ali, A;Abbas, U;
References: Metals Metalloids Soil Plant Water Systems ~ 349-370
Keywords/Products: ICP;ICP-AES;ICP-MS;Meinhard;sample introduction;VG;
Heavy metals are the elements having density higher than that of water. The anthropogenic activities are more significant because they release the heavy metals in bioavailable and mobile forms that can be easily taken up by plants and lead to food chain contamination. Metals and metalloids have so much importance as well as drastic effects on soil, plant and water. Therefore, need to analyze those metals which are toxic and those which are the essential components of the living system. Most effective are x-ray based and spectrometric techniques like ICP-MS, ICP-AES, and EAAS. It is of great concern that phytotoxicity due to accumulation of heavy metals has adverse effects on the crop yield, food safety and marketability. Persistence of heavy metals in soil affects the photosynthesis, gaseous exchange, nutrient absorption and causes the reduction in plant growth. Phytoremediation is a series of plant-based technology that employs natural or genetically modified plants to remove pollutants from contaminated soil and water. Various plants have been proposed in order to improve phytoremediation capabilities through genetic engineering and plant transformation technology. Three most widely used transformation methods are; physical, chemical and biological. According to reports, genetically engineered phytoremediation plants were originally developed to improve resistance to heavy metals. It is a healthy approach to make plants genetically engineer to fight against heavy metal stress.

Bridging the gap of iron deficient foods in low resource setting communities

Date: 2022
Authors: Kwofie, M;
References: Thesis ~ ~
Keywords/Products: Concentric;Meinhard;TR-30-K3;
Iron deficiency anemia (IDA) is a global public health issue affecting people in both developed and developing countries. Iron deficiency occurs when dietary iron absorption is insufficient to meet the body’s iron requirements and losses. Iron deficiency has numerous implications, impacting not only individual health but also community and social growth. Pregnant women, infants, and adolescents are most susceptible to iron deficiency (ID) since they have increased iron requirements. The main cause of iron deficiency (ID) in most developing countries is low dietary iron bioavailability, this according to studies is due to a high intake of cereals, seeds, and grains (plant-based non-heme iron) with limited heme iron and vitamin C (iron absorption enhancers) intake. The absorption of iron from plant-based foods is impeded by the phytate presence in the cereals and grains.Controlling and preventing iron deficiency and anemia in all groups of a population with varying iron requirements necessitates coordinating several initiatives. The objectives of this research study were to (1) find out determinants of iron deficiency (ID) and pathways for improvement among populations in a low resource setting communities, (2) examine the trends and evolving methods (strategies) of managing iron deficiency anemia and the (3) Evaluation of adjusted infants six-twelve months home-made cereal-based foods with heme and iron absorption enhancers to support optimum iron availability. The main causes of iron deficiency (ID) in a low resource setting communities were reviewed and determined, and to better address, the iron deficiency (ID) challenge, strategies for its prevention and management were also evaluated. Since iron deficiency’s long-term effects on infants and young children are detrimental, cereals and grains such as rice, corn, and millet frequently used in infants’ complementary foods preparation in a low resource setting communities were sampled and developed into iron-rich infant foods, other ingredients such as chicken, pumpkin seeds, fruits, and soya beans were added in the product's preparation in accordance with the world health organization’s (WHO) recommendations for the inclusion of at least four items from the seven (7) food groups aimed at dietary diversification to produce adjusted infant porridges which contain heme and vitamin C to support adequate iron absorption from cereal-based infant foods. The study findings suggest iron from adjusted rice porridge is more bioavailable, this is followed by adjusted corn porridge before the adjusted millet porridge

Separation of rare earths by non-aqueous solvent extraction

Date: 2022
Authors: Dewulf, B;
References: Thesis ~ ~
Keywords/Products: Meinhard;
Solvent extraction is widely used for the separation of mixtures of rare earths on an industrial scale. However, these separation processes are not very efficient so that many extraction stages are required to produce pure rare earths. In this project, we develop a new approach to separation of rare earths: non-aqueous solvent extraction with two immiscible organic phases. Non-aqueous solvent extraction offers some advantages compared to conventional solvent extraction with an aqueous feed phase. The speciation of rare-earth ions in non-aqueous solutions often differs greatly, hence influencing the extraction. Making use of these differences, novel and very selective separation processes can be developed. Research efforts were directed towards the development of a continuous non-aqueous solvent extraction process for separation of a rare-earth concentrate by means of mixer-settler cascades.


Date: 2022
References: Mühendislik Bilimleri ve Tasar?m Dergisi 10 680-697
Keywords/Products: Meinhard;Quartz Nebulizer;
Bu çal??mada, Antalya ili Akdeniz Üniversitesi Kampüs alan?nda 2020 y?l?nda toplanan fraksiyonel numunelerdeki suda çözünmeyen partiküllerin morfolojik yap?lar?n?n, boyut da??l?mlar?n?n ve kimyasal bile?imlerinin karakterize edilmesi amaçlanm??t?r. Ayr?ca her bir ya?mur olay?n?n fraksiyonel (s?ral?) örneklerinde majör iyonlar ve bu iyonlar?n fraksiyonel da??l?mlar?, nötralizasyon faktörleri belirlenmi?, bulutla ta??nan (rainout) ve bulut alt? y?kama (washout) mekanizmalar? ile hangi oranlarda al?c? ortama geldikleri hesaplanm??t?r. Çal??mada kullan?lan üç ya?mur olay?ndan birisi olan D-serisi, 07.12.2020 tarihinde örneklenmi? ve bu ya?mur olay?ndan 4 adet fraksiyonel örnek toplanm??t?r. 10.12.2020 tarihli E-serisine kar??l?k gelen ya?mur olay?nda ise 8 adet ve 12.12.2020 tarihli F-serisi ya?mur olay?nda da 10 adet fraksiyonel ya?mur suyu örnekleri toplanm??t?r. Elde edilen sonuçlar çe?itli istatistiksel programlar ile de?erlendirilerek, ç?kan sonuçlar?n veri kaliteleri ve kaynak belirleme çal??malar? yap?lm??t?r. Örneklerde ortalama pH de?erleri 6.06-7.13 aral???nda gözlemlenmi? ve herhangi bir ?ekilde asit ya?muru olas?l???na rastlan?lmam??t?r. Ya?mur örneklerinde partikül boyut analiz sonuçlar?nda D-serisi örneklerde en yüksek ölçülen de?er 33.339 µm, E-serisi örneklerde 53.714 µm olarak ölçülmü?tür ve F serisi örneklerde ölçüm yap?lamam??t?r. Örneklenen ya?mur olaylar?n?n ta??n?m bölgelerinin belirlenebilmesi için geri yörünge hesaplamalar? yap?lm??, kaynak bölgeleri, kaynak türleri ve kirletici içerikleri tart???lm??t?r.

Assessment by a multi-technique approach of PtNPs' transformations in waters under relevant environmental concentrations and conditions

Date: 2022
Authors: Sánchez-Cachero, A;Fariñas, NR;Ríos, Á;Martín-Doimeadios, RDCR;
References: The Science of the total environment 861 160686
Keywords/Products: ICP;ICP-MS;Meinhard;
Once released to the environment, platinum nanoparticles (PtNPs) can undergo different transformations and are affected by several environmental conditions. An only analytical technique cannot provide all the information required to understand those complex processes, so new analytical developments are demanded. In the present work, the potential of asymmetric flow field flow fractionation hyphenated to inductively coupled plasma mass spectrometry (AF4-ICP-MS) for these studies, has been investigated, and classical dynamic and electrophoretic light scattering (DLS & ELS) have been used as complementary techniques. The role of ionic strength, ionic water composition, and natural organic matter (NOM) in the behaviour of PtNPs of different sizes (5 and 50 nm) has been specifically studied. Dynamic and electrophoretic light scattering have been used to track changes in the hydrodynamic diameters (dh) and polydispersity index (PdI) for 50 nm PtNPs (5 nm cannot be studied by DLS) and Z-potential values (for all sizes) to monitor aggregation. AF4-ICP-MS has been also employed to have a solid insight of aggregation at low environmental concentrations for different sizes of PtNPs simultaneously. The information gathered with those techniques was useful to observe changes as the ionic strength increases, which induces aggregation. Also, it was observed that this aggregation process was attenuated in the presence of organic matter. This approach, based on complementary analytical techniques, is needed for a comprehensive study of such complex interactions of NPs in the environment. AF4-ICP-MS is still under-exploited but shows a great potential for this purpose, especially low size NPs and concentrations.

Zero-Interfacing ?HPLC to ICPMS

Date: 2022
Authors: Zhou, Y;Song, X;Yan, X;Yang, L;Chen, S;Wang, Q;
References: Analytical chemistry 94 16975-16979
Keywords/Products: Concentric;Concentric nebulizer;ICP;ICPMS;Meinhard;
The chromatography-mass spectrometry hyphenated technique is the most widely adopted tool for quantifying trace analytes in a complex biosample. One issue we frequently encountered, however, is that the separated analyte-containing chromatographic peaks broaden and even remix prior to mass spectrometric quantification due to the inevitable molecular diffusion within the dead-volume introduced by hyphenation. We developed a zero-interfacing approach for coupling microbore (?) HPLC with inductively coupled plasma mass spectrometry (ICPMS). Zero-interfacing ?HPLC to ICPMS has been achieved by a column-nebulizer assembly (COL-NEB) of a self-designed glass framework with a tapered nozzle, in which a capillary chromatographic column can be harbored while an Ar gas flow is blown through the nozzle mouth. The COL-NEB can be positioned just before the base of the Ar-ICP serving as the central sampling channel of a conventional Ar-ICP torch for online nebulization and transportation of the analytes separated on ?HPLC into ICPMS, maintaining the molecular resolution obtained on ?HPLC and the limit of detection (LOD) of ICPMS. For example, the full width at half-maximum of a SLUGT peptide chromatographic peak was reduced to 1.71 ± 0.07 s (n = 5) with a 0.72 fg LOD (3?) of 80Se. Moreover, at least 32 Se-containing peptides were determined in the trypsin lysate of the water-soluble fraction (?3000 MW) from Se-enriched yeast CRM SELM-1 within a 10 min run, the highest record to date. We believe such an approach paves the way to determining accurate information on a heteroatom and its binding biomolecules that play key roles during life processes.

Gadolinium ecotoxicity is enhanced in a warmer and acidified changing ocean as shown by the surf clam Spisula solida through a multibiomarker approach

Date: 2022
Authors: Figueiredo, C;Grilo, TF;Oliveira, R;Ferreira, IJ;Gil, F;Lopes, C;Brito, P;Ré, P;Caetano, M;Diniz, M;Raimundo, J;
References: Aquatic toxicology (Amsterdam, Netherlands) 253 106346
Keywords/Products: Concentric;ICP;ICP-MS;Meinhard;NexION;
Humans have exhaustively combusted fossil fuels, and released pollutants into the environment, at continuously faster rates resulting in global average temperature increase and seawater pH decrease. Climate change is forecasted to exacerbate the effects of pollutants such as the emergent rare earth elements. Therefore, the objective of this study was to assess the combined effects of rising temperature (? = + 4 °C) and decreasing pH (? = - 0.4 pH units) on the bioaccumulation and elimination of gadolinium (Gd) in the bioindicator bivalve species Spisula solida (Surf clam). We exposed surf clams to 10 µg L-1 of GdCl3 for seven days, under warming, acidification, and their combination, followed by a depuration phase lasting for another 7 days and investigated the Gd bioaccumulation and oxidative stress-related responses after 1, 3 and 7 days of exposure and the elimination phase. Gadolinium accumulated after just one day with values reaching the highest after 7 days. Gadolinium was not eliminated after 7 days, and elimination is further hampered under climate change scenarios. Warming and acidification, and their interaction did not significantly impact Gd concentration. However, there was a significant interaction on clam's biochemical response. The augmented total antioxidant capacity and lipid peroxidation values show that the significant impacts of Gd on the oxidative stress response are enhanced under warming while the increased superoxide dismutase and catalase values demonstrate the combined impact of Gd, warming & acidification. Ultimately, lipid damage was greater in clams exposed to warming & Gd, which emphasizes the enhanced toxic effects of Gd in a changing ocean.

Sustainable PHBH-Alumina Nanowire Nanocomposites: Properties and Life Cycle Assessment

Date: 2022
Authors: Ibarretxe, J;Alonso, L;Aranburu, N;Guerrica-Echevarría, G;Orbea, A;Iturrondobeitia, M;
References: Polymers 14
Keywords/Products: Concentric;Concentric nebulizer;Meinhard;
Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a bio-based polyester with the potential to replace some common polymers of fossil origin. However, PHBH presents serious limitations, such as low stiffness, tendency to undergo crystallization over long time periods and low resistance to thermal degradation during processing. In this work, we studied the use of alumina nanowires to generate PHBH-alumina nanocomposites, modifying the properties of PHBH to improve its usability. Solvent casting and melt blending were used to produce the nanocomposites. Then, their physicochemical properties and aquatic toxicity were measured. Finally, LCA was used to evaluate and compare the environmental impacts of several scenarios relevant to the processing and end of life (EoL) conditions of PHBHs. It was observed that, at low concentrations (3 wt.%), the alumina nanowires have a small positive impact on the stiffness and thermal degradation for the samples. However, for higher concentrations, the observed effects differed for each of the applied processing techniques (solvent casting or melt blending). The toxicity measurements showed that PHBH alone and in combination with alumina nanowires (10 wt.%) did not produce any impact on the survival of brine shrimp larvae after 24 and 48 h of exposure. The 18 impact categories evaluated by LCA allowed defining the most environmentally friendly conditions for the processing and EoL of PHBHs, and comparing the PHBH-related impacts to those of some of the most common fossil-based plastics. It was concluded that the preferable processing technique for PHBH is melt blending and that PHBH is unquestionably more environmentally friendly than every other analyzed plastic.

Risk Assessment of Essential and Toxic Elements in Freshwater Fish Species from Lakes near Black Sea, Bulgaria

Date: 2022
Authors: Peycheva, K;Panayotova, V;Stancheva, R;Makedonski, L;Merdzhanova, A;Parrino, V;Nava, V;Cicero, N;Fazio, F;
References: Toxics 10
Keywords/Products: Concentric;Meinhard;Type C;
The aims of this study were to measure the concentrations of selected toxic and essential elements in the muscle tissue of five common freshwater fish species ((roach (Rutilus rutilus), freshwater bream (Abramis brama), prussian carp (Carassius gibelio), crucian carp (Carassius carassius) and common carp (Cyprinus carpio)) from Lake Burgas and Lake Mandra (Bulgaria). In all samples the levels of Cd, Cr, Cu, Mn, Ni, Pb, Fe and Zn were under the maximum allowed concentrations for safe human consumption in Bulgaria and ranged as follows: Cd 0.02-0.05; Cr 0.03-0.06; Cu 0.11-0.20; Mn 0.05-0.71; Ni 0.06-0.11; Pb 0.15-0.27, Fe 1.68-5.86 and Zn 1.94-9.06 mg/kg wet weight. The concentration of As was under detection limit. An assessment of the human risk by calculation of the target hazard quotients (THQ), hazard index (HI) and target risk (TR) was performed. The target hazard quotient (THQ) for individual elements and HI for combined metals were lower than 1, indicating no health risk for consumers due to the intake of either individual or combined metals. The target risk for iAs, Pb and Ni was below 10-6, indicating no carcinogenic risk. According to these results, the consumption of these freshwater fish species is safe for human health.

Characterization of a high-sensitivity ICP-TOFMS instrument for microdroplet, nanoparticle, and microplastic analyses

Date: 2022
Authors: Harycki, S;Gundlach-Graham, A;
References: Journal of Analytical Atomic Spectrometry 38 111-120
Keywords/Products: Droplet;ICP;Meinhard;Quartz Nebulizer;
We report the capabilities of an inductively coupled plasma time-of-flight mass spectrometry (ICP-TOFMS) instrument for single-droplet and single-particle analysis.

Detection of PTFE microparticles by ICP-qMS operated in single-particle mode

Date: 2022
Authors: Gelman, F;Muszy?ska, M;Karasi?ski, J;Lev, O;Halicz, L;
References: Journal of Analytical Atomic Spectrometry 37 2282-2285
Keywords/Products: ICP;Meinhard;
In this study, we examine the possibility of detecting PTFE microparticles by ICP-qMS equipped with O2 dynamic reaction cell (DRC) and operated in single-particle mode.

From Nuclear Reactor-Based to Proton Accelerator-Based Therapy: The Finnish Boron Neutron Capture Therapy Experience

Date: 2022
Authors: Porra, L;Wendland, L;Seppälä, T;Koivunoro, H;Revitzer, H;Tervonen, J;Kankaanranta, L;Anttonen, A;Tenhunen, M;Joensuu, H;
References: Cancer biotherapy & radiopharmaceuticals
Keywords/Products: Meinhard;
The authors review the results of 249 patients treated with boron neutron capture therapy (BNCT) at the Helsinki University Hospital, Helsinki, Finland, from May 1999 to January 2012 with neutrons obtained from a nuclear reactor source (FiR 1) and using l-boronophenylalanine-fructose (l-BPA-F) as the boron delivery agent. They also describe a new hospital BNCT facility that hosts a proton accelerator-based neutron source for BNCT. Most of the patients treated with nuclear reactor-derived neutrons had either inoperable, locally recurrent head and neck cancer or malignant glioma. In general, l-BPA-F-mediated BNCT was relatively well tolerated with adverse events usually similar to those of conventional radiotherapy. Twenty-eight (96.6%) out of the evaluable 29 patients with head and neck cancer and treated within a clinical trial either responded to BNCT or had tumor growth stabilization for at least 5 months, suggesting efficacy of BNCT in the treatment of this patient population. The new accelerator-based BNCT facility houses a nuBeam neutron source that consists of an electrostatic Cockcroft-Walton-type proton accelerator and a lithium target that converts the proton beam to neutrons. The proton beam energy is 2.6 MeV operating with a current of 30?mA. Treatment planning is based on Monte Carlo simulation and the RayStation treatment planning system. Patient positioning is performed with a 6-axis robotic image-guided system, and in-room imaging is done with a rail-mounted computed tomography scanner. Under normal circumstances, the personnel can enter the treatment room almost immediately after shutting down the proton beam, which improves the unit capacity. ID: NCT00114790.

Sex-dependent vascular effects of cadmium sub-chronic exposure on rats

Date: 2022
Authors: de Oliveira, TF;Rossi, EM;da Costa, CS;Graceli, JB;Krause, M;Carneiro, MTWD;Almenara, CCP;Padilha, AS;
References: Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine ~ ~
Keywords/Products: Concentric;Meinhard;
Cadmium exposure is related to several cardiovascular diseases, such as hypertension, atherosclerosis and endothelial dysfunction. However, the toxic effect of cadmium can be dependent on the sex when examined sex in experimental models. The aim of this study was to analyze the effects of cadmium exposure on the cardiovascular system of male and female rodents. The experiments were carried out on both-sexes Wistar at 4 months of age, where from 3 months onwards, cadmium (CdCl2 100 mg/l in placed the drinking water for 30 days) or vehicle delivered (distilled water) was ingested. Before and after 30 days of exposure to cadmium, systolic blood pressure was regularly measured. After exposure, blood was collected to measure dosage of cadmium, in male and female, and estrogen in females. Vascular reactivity to phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP) was studied at respective isolated aortic segments. After the period to Cd-exposure, systolic blood pressure was increased only in the male rats. Males also had higher levels of plasma cadmium than those of female rats, and exposure to the metal did not affect the amount of estrogen produced in the female rats. Increased myeloperoxidase (MPO) activity was also observed in both the males and females that had been exposed to the metal. Moreover, exposure to the cadmium reduced the ACh relaxation and increased vascular reactivity to Phe, resulting in an imbalance between nitric oxide superoxide anion in the isolated aorta of male rats. In female rats, sub-chronic cadmium exposure did not modify the vascular reactivity to Phe and neither to the ACh. The present study revealed that the Cd exposure for 30 days induced sex-dependent cardiovascular abnormalities.