Search

In this work, the potential for direct major component analysis of lithium-nickel-manganese-cobalt oxide variants in solid samples by graphite furnace atomic absorption spectrometry (SS-GF AAS) was critically evaluated, always with the aim of developing a simple and rapid method that relies only on the use of aqueous standards for calibration. The accuracy of the developed method was evaluated against an established wet chemical acid digestion method using an inductively coupled plasma optical emission spectrometer (ICP-OES). The most challenging aspect was the selection and use of suitable standards, whereby the analytical performance criteria of liquid standards, single oxide solid standards and multielement solid standards had to be determined. With the result that multi-element liquid standards can be used for calibration, very good agreement with the certified reference values and with the values obtained by ICP-OES was achieved in all cases. The precision of the method was better than 12% with an optimum sample mass of 0.2-0.4 mg. The results show that not only the major components in pure NMC compounds (e.g. starting materials) can be reliably analysed, but also the cathode coatings made from recycled battery materials. This demonstrates the range of applications of the methods and their suitability under industrial conditions, for example in the analysis of recyclates. The technology is almost predestined for use in industrial laboratories in order to quickly and accurately determine the stoichiometric composition of cathode coatings from aged lithium batteries and to ensure battery shredding by type. [ABSTRACT FROM AUTHOR]

A new method for the determination of ultra-trace cobalt by ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) and graphite furnace atomic absorption spectrometry (GFAAS) was developed. The trace cobalt was extracted by DLLME using the homemade reagent 2-(5-bromo-2-pyridylazo)-5-dimethylaminobenzenamine (5-Br-PADMA) as chelating agent, the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6mim][PF6]) as extractant, and acetonitrile (CH3CN) as dispersing agent, and then determined by GFAAS. The factors affecting the cobalt extraction efficiency: the type and volume of extraction solvent and dispersive solvent, the concentration and dosage of chelating agent, and the pH of the solution, were explored using the one-way rotation method. Under the optimized conditions, the cobalt concentration showed excellent linearity in the range of 0.05–1.50 ng/mL with the detection limit of 0.026 ng/mL; the relative standard deviation (RSD) for the determination of the cobalt standard solution with the mass concentration of 1.0 ng/mL was 4.83% (n = 9). From the slope of the linear regression equation for the determination of cobalt obtained after extraction compared with that before extraction, the enrichment factor of the method was found to be 62, and the spiked recoveries were in the range of 94.0–104.4%. The method is characterized by low detection limit, high sensitivity, and environment friendliness as well as convenient and rapid operation for the determination of trace cobalt in water samples. The results of this method are satisfactory. [ABSTRACT FROM AUTHOR]

In this study, we report a novel platinum–doxorubicin conjugate that demonstrates superior therapeutic indices to cisplatin, doxorubicin, or their combination, which are commonly used in cancer treatment. This new molecular structure (1) was formed by conjugating an amphiphilic Pt(IV) prodrug of cisplatin with doxorubicin. Due to its amphiphilic nature, the Pt(IV)–doxorubicin conjugate effectively penetrates cell membranes, delivering both cisplatin and doxorubicin payloads intracellularly. The intracellular accumulation of these payloads was assessed using graphite furnace atomic absorption spectrometry and fluorescence imaging. Since the therapeutic effects of cisplatin and doxorubicin stem from their ability to target nuclear DNA, we hypothesized that the amphiphilic Pt(IV)–doxorubicin conjugate (1) would effectively induce nuclear DNA damage toward killing cancer cells. To test this hypothesis, we used flow the cytometric analysis of phosphorylated H2AX (γH2AX), a biomarker of nuclear DNA damage. The Pt(IV)–doxorubicin conjugate (1) markedly induced γH2AX in treated MDA-MB-231 breast cancer cells, showing higher levels than cells treated with either cisplatin or doxorubicin alone. Furthermore, MTT cell viability assays revealed that the enhanced DNA-damaging capability of complex 1 resulted in superior cytotoxicity and selectivity against human cancer cells compared to cisplatin, doxorubicin, or their combination. Overall, the development of this amphiphilic Pt(IV)–doxorubicin conjugate represents a new form of combination therapy with improved therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Purpose: Short stature is prevalent among children worldwide, particularly in developing countries. Various trace elements, including zinc, magnesium, iron, copper, chromium and selenium, are crucial for proper body development. The aim of this study is to explore the relationship between trace elements and TNF-α and IL-6 to elicit and possible pathway responsible for short stature. Methods: Two hundred and twenty samples were recruited for this study, 100 short statures and 120 controls were randomly selected. Six trace elements were measured using graphite furnace atomic absorption spectrometry. The concentrations of IL-6 and TNF-α in serum were assessed utilizing the Enzyme-Linked-Immunosorbent Assay (ELISA). Superoxide dismutase was also analysed to determine the oxidative stress response. Results: The study revealed notable distinctions in serum trace element levels of short stature. They exhibited significant lower levels of zinc and magnesium, alongside higher levels of copper. The altered Cu/Zn ratio seemed to have a positive correlation with short stature. Conversely, no significant disparities were observed in iron, chromium, and selenium levels. Furthermore, a significant rise was noted in proinflammatory marker TNF-α and cytokine IL-6. Additionally, superoxide dismutase was low in the short statures In silico study shows a high affinity of Zinc with TNF alpha. It may be suggested that inflammation at any time during childhood, with the rise in TNF alpha tightly binds with zinc and may have led to a decrease in zinc serum levels, altered redox homeostasis and resulted in short stature. Conclusion: The altered Cu/Zn ratio along with high TNF alpha and IL6 may be used as a marker for short stature in the initial years of growth in children before they reach maturity at the age of 18. Thereafter, introducing zinc supplementation could potentially enhance stature by mitigating TNF-alpha level. Further experimental studies will help to establish the exact role of zinc with TNF alpha in short stature. [ABSTRACT FROM AUTHOR]

Background: The presence of toxic metals in food can be a risk to food safety and public health. Methods: The Iranian canned tuna was analyzed for nickel level after wet digestion with acids using Graphite Furnace Atomic Absorption Spectrometry (GFAAS). Results: The average concentration of nickel in canned and dead fresh fish found 4.20 ppb and 1.64 ppb. A significant difference in nickel level was observed between canned and dead fresh fish samples in this study. Although the concentration of nickel per g in the fillet after processing was relatively low, but the total amount of nickel in the sample shown change (256.01%). The results in present study showed the protein content in the canned fish increased to 13.17%. The moisture content in the processed fish decreased to 8.80%. The fat content in the canned fish increased to 12.86%. Conclusion: Although the protein and moisture contents significantly increased and decreased respectively after processing, but none of these factors were related to the change in nickel concentration. It may be recommended to regularly monitor the concentration of nickel metal in aquatic food products, so that human health was not at risk. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a toxic metal which is harmful to humans and the environment. Cd levels and adverse effects may be associated with genetic polymorphisms in genes involved in its toxicokinetics. This study investigated Cd levels in 198 residents of a condominium in Rio de Janeiro, Brazil, built on industrial steel slag waste and the influence of glutathione S-transferase pi isoform 1 (GSTP1) rs1695 A>G polymorphism. Polymorphism was genotyped using a validated TaqMan assay; Cd levels were measured in blood (BCd) and urine (UCd) by graphite furnace atomic absorption spectrometry. Associations were evaluated by multiple logistic regression, odds ratios (ORs), and 95% confidence intervals (CIs). The mean Cd levels were 0.70 ± 0.20 µg L−1 (BCd), 0.58 ± 0.57 µg L−1 (UCd), and 0.61 ± 0.65 µg g−1 in urine corrected by creatinine (UcCd), and the Cd results were above tolerable levels (BCd > 0.5 µg L−1) in 87.4% of subjects. Higher blood Cd levels (>0.69 µg L−1) were associated with respiratory disease (OR = 2.4; 95%CI = 1.2–5.0), as almost 30% of people with respiratory diseases had higher Cd levels. The GSTP1 rs1695AA genotype frequency was 38.1%, and there were no significant differences between the SNP and Cd levels. High Cd levels and a high prevalence of diseases highlight the importance of implementing public policies and the continuous monitoring of this at-risk population. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles were evaluated as a potential chemical modifier for lead determination by high-resolution continuum source graphite furnace atomic absorption spectrometry. Hydrophilic palladium nanocubes and palladium nanospheres were synthesised with sizes varying from 3 to 22 nm. Positive effects in terms of sensitivity and thermal stability upon the use of palladium nanoparticles were observed, especially using the 3 nm spherical-shaped. The mass of modifier influenced the thermal stability and relative signal intensity of the analyte, although the effectiveness of the modifier appeared to be suppressed to an important extent in the presence of matrix components of the leached extracts obtained from petroleum wastes. The optimised pyrolysis and atomisation temperatures were, respectively, 800 °C and 2300 °C, using 200 ng of 3 nm palladium nanoparticles. The limit of detection (4 µg L−1) and the precision (better than 18 %) were considered satisfactory for the proposed analysis. The method accuracy, evaluated by recovery tests and by comparison with the results obtained using inductively coupled plasma mass spectrometry, was proven adequate to enable the determination of Pb in leached extracts from petroleum waste. The method was successfully applied to determine lead in leached extracts obtained from oily sludge and drill cuttings and the obtained concentrations ranged from <13 to 354.4 µg L−1. [ABSTRACT FROM AUTHOR]

The philopatric and sedentary nature of female S. canicula, its high abundance as a bycatch and resilience to regular exploitation by bottom trawl fisheries and its widespread distribution, makes it a potentially good candidate as a biomonitor species. To evaluate this potential, microwave-assisted extraction (MAE) and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS) were used to analyse Pb, Cd, and Cu in muscle tissue of individuals captured in the Western Mediterranean (Alicante, Spain). A monthly assessment of the concentration of these three analytes was conducted from November 2019 to November 2020 with 300 individuals. Results showed the existence of slightly higher mean concentrations during warmer seasons for Pb and Cd with mean concentrations for Pb and Cu peaking in Autumn 2019 and during Spring 2020 in the case of Cd. Significant differences in analyte concentrations found between non-consecutive months suggested gradual variability in time. Although space-wise, time-persistent concentration hotspots were observed throughout the sample area, the magnitude of these appeared to be variable in time and should be evaluated in future studies. [ABSTRACT FROM AUTHOR]

The biologically produced gold nanoparticles (AuNPs) are novel carriers with promising use in targeted tumor therapy. Still, there are no studies regarding the efficacy of nanoparticle internalization by cancer and noncancer cells. In this study, AuNPs were produced by Fusarium oxysporum and analyzed by spectrophotometry, transmission electron microscopy (TEM), energy dispersive x‐ray spectroscopy (EDS), and Zetasizer. Obtained AuNPs were about 15 nm in size with a zeta potential of –35.8 mV. The AuNPs were added to cancer cells (4T1), noncancer cells (NIH/3T3), and macrophages (RAW264.7). The viability decreased in 4T1 (77 ± 3.74%) in contrast to NIH/3T3 and RAW264.7 cells (89 ± 4.9% and 90 ± 3.5%, respectively). The 4T1 cancer cells also showed the highest uptake and accumulation of Au (∼80% of AuNPs was internalized) as determined by graphite furnace atomic absorption spectroscopy. The lowest amount of AuNPs was internalized by the NIH/3T3 cells (∼30%). The NIH/3T3 cells exhibited prominent reorganization of F‐actin filaments as examined by confocal microscopy. In RAW264.7, we analyzed the release of proinflammatory cytokines by flow cytometry and we found the AuNP interaction triggered transient secretion of tumor necrosis factor alpha (TNF‐α) and interferon gamma (IFN‐γ). In summary, we proved the biologically produced AuNPs entered all the tested cell types and triggered cell‐specific responses. High AuNP uptake by tumor cells was related to decreased cell viability, while low nanoparticle uptake by fibroblasts triggered F‐actin reorganization without remarkable toxicity. Thus, the biologically produced AuNPs hold promising potential as cancer drug carriers and likely require proper surface functionalization to shield phagocytizing cells. [ABSTRACT FROM AUTHOR]

Nowadays, trace metal contamination within urban atmospheres is a significant and concerning global issue. In the present study, two synanthropic bird species, namely, the feral pigeon (Columba livia f. domestica) and the rook (Corvus frugilegus), were employed as bioindicators to assess the atmospheric trace metal pollution in Iasi City, Romania. The concentrations of Ni, Pb, Cd, Co, Cr, and Cu were determined through high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF-AAS) of various tissues, including the liver, kidney, lung, heart, muscle, and bone, of feral pigeons and rooks collected in Iasi City. The order of trace metal concentrations in the tissues of feral pigeons and rooks in Iasi City was similar: Cu > Pb > Ni > Cd > Cr > Co. However, trace element values in most tissues were higher in the rook samples than in feral pigeon ones, except for Co, which had elevated levels in feral pigeon renal and cardiac tissues, and Cu, which registered the highest concentrations in feral pigeon liver and kidney tissues. While not statistically significant, Pb concentration values in the PM10 fraction of atmospheric particles positively correlated with Pb concentrations in rook kidney samples (p = 0.05). The concentration levels of Cd, Pb, and Ni in the PM10 fraction of air particles showed a positive correlation with Cd levels in the samples of pigeon heart and rook liver, kidney, and heart, Pb levels in the samples of pigeon kidney, heart, and muscle and rook liver and bone, and Ni levels in the samples of pigeon liver, kidney, and bone and rook liver, muscle, and bone, respectively. [ABSTRACT FROM AUTHOR]

This study aims to apply the ionic liquid-based solidified floating organic drop micro-extraction (IL-SFODME) technique to improve the preconcentration of trace mercury levels, serving as a preparatory step for analysis via graphite furnace atomic absorption spectrometry (GFAAS) without using chelating agents. The process involves separating and preconcentrating mercury ions using IL-SFODME, followed by GFAAS analysis. This study systematically examined several factors affecting micro-extraction efficiency, including pH, the amount of ionic liquid 1-Hexyl-3-methylimidazolium hexafluorophosphate (HMIMPF6), extraction time, stirring rate, and temperature, to determine the optimal conditions. Under these optimized conditions, an enhancement factor of 171 was achieved for a 75 mL sample solution. The calibration curve was linear within the 0.5–10 µg/L range, with a detection limit (3σ) of 0.12 µg/L and a quantification limit (10σ) of 0.40 µg/L. The relative standard deviation (RSD) for 7 replicate measurements of 1 µg/L mercury was ±2.78%. The combination of the ionic liquid and SFODME methods without using a chelating agent is used for the first time for metal extraction. The method was successfully applied to extract and determine mercury in reference water samples and various real water samples, demonstrating notably satisfactory extraction efficiency. [ABSTRACT FROM AUTHOR]

Environmental pollution as a result of industrial activity is widespread in many urban areas including Chicago. In an effort to evaluate the heavy metal fraction originating from industrial activities, plant samples of Daucus Carota or wild carrot were collected at or adjacent to six sites located in two of Chicago's designated industrial corridors. Plants, especially herbaceous species, have been deemed suitable as environmental pollution monitors as they are able to provide information about the heavy metal fraction accessible to biota. The leaves of Daucus Carota were acid digested and analyzed with total reflection X‐ray fluorescence spectrometry TXRF. The results showed elevated heavy metal mass fractions for at least one collection site which is close to an operational railyard. Other studies investigating heavy metals in proximity to railroad operations found elevated mass fractions for several elements, but specifically manganese as well. This suggests that abrasion from shunting and breaking releases certain pollutants into the local environment. The data were compared with studies executed in Rome, Italy, and Pakistan, which used Daucus Carota to evaluate heavy metal pollution. It was found that the heavy metal mass fractions obtained for Chicago were higher for some elements indicating an increased pollutant burden for these elements. The same samples were also analyzed by graphite furnace atomic absorption spectrometry GFAAS for the elements copper and lead and the data compared. Those two elements were chosen as they were present at each location and GFAAS has proven to be highly sensitive for them. It was found that the two methods provided comparable results for copper, whereas for lead, TXRF overestimated the mass fractions most likely due to limitations of the spectra evaluation software. The analysis of a certified reference material ‘BCR 679 white cabbage’ showed that most data obtained by TXRF were in good agreement with the certified values, with the exception of lead, which was not certified. However, since GFAAS has high sensitivity toward lead and is considered reference method for that element by regulatory agencies, a comparison between GFAAS and TXRF data for lead in the same sample can serve as good indicator for TXRF performance. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive overview of solidified floating organic drop microextraction, with a particular emphasis on its applications in the analysis of heavy metal ions and different pharmaceutical compounds by sample pretreatment, complexation, and their identification by various analytical techniques. Here, we discussed basic principles, procedures, applications of the technique, and effects of different variables like pH, temperature, stirring rate, extraction time, salts addition, extraction solvent and extraction volume, centrifugation speed, and, vortex time on preconcentration. In brief, the review summarises the various modes of solidified floating organic drop microextraction such as dispersive liquid‐liquid microextraction, ultrasound‐assisted, air‐assisted liquid‐liquid microextraction, and vortex‐assisted solidified floating organic drop microextraction. this review covers the methods combined with analytical techniques such as inductively coupled plasma‐optical emission spectrometry, electrothermal atomic absorption spectrometry, flame atomic absorption spectroscopy, graphite furnace atomic absorption spectrometry, electrothermal vaporization inductively coupled plasma mass spectrometry, high‐performance liquid chromatography, and gas chromatography/mass spectrometry. among these, the incorporation of ultrasonic, vortex, and air agitation improves the dispersion mechanism. The coupling of solidified floating organic drop microextraction with other techniques enhances the selectivity and efficiency of the preconcentration procedure. This review provides a potential overview of the fundamental principles, advancements in various modes, influencing factors, and applications of solidified floating organic drop microextraction, showing its potential for advancements in sample preparation and analytical methodologies across various domains. [ABSTRACT FROM AUTHOR]

In the present study, an efficacious, safe, inexpensive and eco-friendly microextraction was provided by deep eutectic solvents based on dispersive liquid–liquid microextraction (DLLME − DES) followed by GFAAS. A series of DESs were synthesised using l-menthol as hydrogen bond acceptor (HBA) and carboxylic acids with 4, 6, 8 and 10 carbon atoms as hydrogen bond donors (HBD). The synthesised DESs were used as extractants of arsenic ions. Under optimised conditions, good linearity with coefficient of determination (r2) 0.992 and an acceptable linear range of 0.3–100 µg kg−1 was obtained. The limit of detection was 0.1 µg kg−1 (S/N = 3) for arsenite (As(III)) ions, and a high enrichment factor (EF = 200) was obtained. The enhancement factor and extraction recovery (ER%) of the method were 340 and 60%, respectively. RSDs including inter- and intra-day ranged from 3.2% to 5.8% in three examined concentrations. After a specific digestion, the capability of the synthesised DES in the extraction of As(III) from rice was tested. Total inorganic arsenic was separated similarly after reduction of arsenate (As(V)) to As(III), and As(V) concentration was calculated by difference. Using a second digestion method, total arsenic concentration (sum of organic and inorganic arsenic) in the samples was determined. [ABSTRACT FROM AUTHOR]

Background: School meals represent a significant supply of nutrients for children in Brazil, especially those in conditions of social vulnerability. Objectives: This study aimed to assess the levels of arsenic (As), cadmium (Cd), and lead (Pb) in meals served in public elementary schools in four municipalities in the state of Bahia, Brazil, and assess the risk posed to children's health. Methods: Ninety-six samples were collected from 16 schools, freeze-dried, and subjected to microwave-assisted digestion. The As, Cd, and Pb levels were determined by graphite furnace atomic absorption spectrometry. The risk assessment was based on calculating each element's hazard quotient (HQ). Results: None of the samples reached or exceeded the tolerable levels for the elements analyzed. Pb was the metal that obtained the most significant result, reaching maximum levels of 39–157 µg·kg−1. Conclusions: No element exceeded the PTWI proposed by JECFA; thus, the toxic metal content in school meals poses a negligible risk to children's health. [ABSTRACT FROM AUTHOR]

This study aims to investigate the vegetative buds from Picea abies (spruce), naturally found in a central region of Romania, through a comprehensive analysis of the chemical composition to identify bioactive compounds responsible for pharmacological properties. Using HPLC/derivatization technique of GC-MS and quantitative spectrophotometric assays, the phenolic profile, and main components of an ethanolic extract from the buds were investigated. The essential oil was characterized by GC-MS. Moreover, the antioxidant activity with the DPPH method, and the antimicrobial activity were tested. Heavy metal detection was performed by graphite furnace atomic absorption spectrometry. The main components of the alcoholic extract were astragalin, quercetin, kaempferol, shikimic acid, and quinic acid. A total content of 25.32 ± 2.65 mg gallic acid equivalent per gram of dry plant (mg GAE/g DW) and of 10.54 ± 0.083 mg rutin equivalents/g of dry plant (mg RE/g DW) were found. The essential oil had D-limonene, α-cadinol, δ-cadinene, 13-epimanool, and δ-3-carene as predominant components. The spruce vegetative buds exhibited significant antioxidant activity (IC50 of 53 μg/mL) and antimicrobial effects against Staphylococcus aureus. Furthermore, concentrations of heavy metals Pb and Cd were below detection limits, suggesting that the material was free from potentially harmful contaminants. The results confirmed the potential of this indigenous species to be used as a source of compounds with pharmacological utilities. [ABSTRACT FROM AUTHOR]

In recent decades, tattooing has become a form of social and artistic expression. To apply a tattoo, the skin is marked by the internal injection of ink in the skin. Hence, it includes human health exposure to metals since the tattoo ink composition includes such elements. The present paper reports the determination and quantification of 8 elements (As, Cd, Co, Cr, Cu, Hg, Ni, Pb) in twenty tattoo ink colors available in the Greek market imported from the USA and China. The elemental content was carried out by atomic absorption spectrometry after microwave-assisted digestion. A comparison was carried out between the results of the present study and the maximum permitted concentrations as proposed in the ResAP and EPA guidelines, while the level of dermal exposure due to pigment application through ink injection was also estimated. All inks contained Cr, Cu, Ni, and Pb, while the content of As, Cd, and Co was below the detection limit in certain samples. Mercury was determined in three samples. Chromium, Cu, and Ni were present in the highest concentrations, while Cd and Hg contents were in general low. Most elements presented their maximum levels in the brown ink originating from USA. [ABSTRACT FROM AUTHOR]

The document is a contents list for the Journal of Analytical Atomic Spectrometry. It includes the ISSN, cover image, and inside cover image for the current issue. The contents list also provides information on various articles and papers featured in the journal, covering topics such as atomic spectrometry updates, in situ online detection of atmospheric particulate matter, high-sensitivity analysis of trace elements in water, and other related subjects. The journal aims to connect the world with the chemical sciences and is published by The Royal Society of Chemistry. [Extracted from the article]

A novel graphene oxide (GO) mediated dispersive micro solid phase extraction procedure is developed for the extraction of ultratrace beryllium from effluents of beryllium processing plants. These effluents are alkaline in nature due to the extraction of Be as Be(OH)2. In this process, GO and 1-octanol are used as micro sorbant and extracting agents, respectively. In alkaline effluents, the negative charges on GO nanosheets help in enhancing the dispersibility and sorption capacity. These highly dispersed GO nanosheets effectively interacted with the targeted Be species instantaneously and Be is sorbed quantitatively from the aqueous phase onto their reactive solubilizing sites. The separation and preconcentration of Be sorbed GO are achieved by reducing its hydrophilicity. This is achieved by the addition of an electrolyte, NaCl, which initiates the cation-induced surface charge neutralization of GO. Due this process the π–π interactions dominate over electrostatic repulsion between GO nanosheets, resulting in coagulation and the formation of bulky GO aggregates. These aggregates are easily extracted quantitatively from the bulk aqueous phase into a small 1-octanol phase through hydrophobic interactions. Ultrasonic back extraction of Be is carried out into dilute nitric acid from 1-octanol. The levels of Be in dilute nitric acid are quantified using GFAAS. Under optimized conditions, the preconcentration factor and limit of detection are 100 and 0.002 ng mL−1, respectively, for 50 mL sample. The recoveries are in the range from 90 to 112% at 50–200 pg mL−1. [ABSTRACT FROM AUTHOR]

A new automated method was developed combining the features of the salting-out effect, single-phase liquid–liquid extraction (SPLLE), and flow-batch analysis to determine Cr(VI) in river water samples by graphite furnace atomic absorption spectrometry. A water–ethanol–amyl alcohol mixture containing sodium diethyldithiocarbamate (NaDDTC) as the chelating agent was also employed. Before spectrometric measurements, the salting-out effect allowed fast single-phase separation and preconcentration of the complex Cr(VI)-DDTC. The extraction procedure was performed inside the mixing chamber of the flow-batch analyzer, simplifying the overall design. Less sample dilution and reduced volume of the organic phase were achieved by studying the phase diagram of the ternary system. Spectrometric operational parameters, the composition of the water–ethanol–amyl alcohol mixture, the concentration of the chelating agent, the concentration of the saline solution, and the parameters of the flow-batch system were optimized. Characteristic mass, sample throughput, limit of detection, limit of quantification, and enrichment factor were 0.33 pg, 129 samples h−1, 0.05 μg L−1, 0.17 μg L−1, and 7.3, respectively. The proposed method's accuracy was evaluated by analysis of a certified reference material and recovery tests, which resulted in a relative error of 2.94% and recovery rates ranging from 96 to 102%. The proposed method proved to be simple and effective for determining Cr(VI) in river water samples and could be used in further investigations regarding the determination/speciation of other chemical elements. [ABSTRACT FROM AUTHOR]

Despite the importance of breastfeeding, complementary or complete feeding with infant formula is performed worldwide. Metal contaminants, especially lead and cadmium, have many toxic and adverse effects, especially in children. Therefore, this work was conducted to investigate the levels of lead and cadmium in infant formula and baby foods. This study was performed on 18 samples of infant formula and 7 samples of baby food. Random sampling was performed among the best-selling and most consumed brands available in the Zahedan market, and elements were measured by atomic absorption spectroscopy using a graphite furnace. Moreover, Estimated Daily Intake (EDI) and health risk index (HRI) were calculated for the average of the total data. The mean concentrations of lead in infant formula and baby food samples were 14.7±0.98 and 13.77±1.51 µg/kg, respectively; lead was observed in all samples, although the difference between the amount of lead in samples no. 2 and no. 9 and its standard amount was significant (p<0.05). The average concentrations of cadmium in infant formula and baby food samples were 0.097±0.016 and 0.705±0.12 µg/kg, respectively; it was observed in 22% of infant formula samples and 57% of baby food samples, but the difference in cadmium concentrations in the samples was not significant compared to the standard concentration (p>0.05). The highest EDI for lead in infant formula for ages of 0 to six months was 0.22 µg/kg.day.bw. Also, the HRI for all samples was much less than one, which indicates that the baby's food and infant formula are healthy in terms of daily intake of cadmium and lead. Finally, it can be concluded that the amount of cadmium and lead in the infant formula and baby food samples, according to some indicators, is less than the standard level. [ABSTRACT FROM AUTHOR]

The document is a contents list for the Journal of Analytical Atomic Spectrometry. It includes the ISSN, cover artwork, and a list of articles and papers featured in the issue. Topics covered in this issue include advances in the analysis of clinical and biological materials, foods and beverages, as well as the detection of tritium using ultrafast laser-induced breakdown spectroscopy. The journal is published by The Royal Society of Chemistry, a leading chemistry community. [Extracted from the article]

Boron trace determination in biological materials is needed in different fields of application. Direct B determination by means of Graphite Furnace Atomic Absorption Spectrometry (SS-GFAAS) has been used in the past for this purpose, offering good detection limits hardly achievable by other techniques. However, such methods require the use of high atomization temperatures combined with large integration times to promote B atomization, which dramatically reduces the lifetime of the instrument's graphite parts. In this work, a new perspective for B determination by means of Graphite Furnace Molecular Absorption Spectrometry (GFMAS) is proposed. B was detected as the diatomic molecule BF (boron monofluoride), deploying a gas phase reaction with CH3F as fluorinating agent. Based on this strategy, a method for the direct determination of B in two biological certified reference materials (NIST SRM 1570a spinach leaves and NIST SRM 1573a tomato leaves) has been developed, providing similar detection capabilities to the GFAAS method (LOD of 0.24 ng) but requiring much milder furnace conditions. Moreover, the appearance of memory effects, very common in GFAAS methods, is also avoided with this method. Straightforward calibration with aqueous standard solutions was also found to be possible. To this end, a mixture of W (permanent), citric acid, and Ca as chemical modifiers was found to be essential for obtaining a reproducible and sufficiently sensitive signal for boron solutions, comparable to the signals obtained for the solid samples. With this method, accurate results were obtained for the direct analysis of both certified reference materials, provided that spectral interferences from the PO molecule were properly corrected. Precision values in the range of 15% RSD, as typically reported for direct solid sampling GFAAS, were found. Finally, and as an additional advantage of the GFMAS method, a large isotopic shift in the absorbance of the 10BF and 11BF molecules can be accurately monitored at a secondary transition for the BF molecule. This offers novel analytical possibilities for the method, which are also explored in this study. In this regard, control of the B concentration was found to be critical for obtaining accurate and precise isotope ratios for this element. [ABSTRACT FROM AUTHOR]

The developments of electrothermal atomic absorption spectrometry and high-resolution continuum source - graphite furnace atomic absorption spectrometry, have enabled the utilization of conventional and permanent chemical modifiers in determining especially, volatile and moderately-volatile elements in various sample solutions. Chemical modifiers used in the determination of elements have changed the thermochemical behaviors of both analyte and sample matrix by increasing the pyrolysis temperature of analyte up to a higher stable condition. They may also help to control various analytical parameters such as accuracy and precision, and to reduce interferences in sample matrixes. Conventional modifiers such as Pd, Rh, Ru and Pd + Mg mixture together with sample solution and permanent modifiers such as Pd, W-Rh, W-Pd, Zr-Pd and Zr-Ru coated on pyrolytic graphite tubes have been utilized for the determination and the detection limits of volatile and moderately-volatile elements such as Cd, Pb, As, Se, Sn, Sb, Cr, Bi, Cu, Mn and Fe in various samples in recent years. [ABSTRACT FROM AUTHOR]

Graphite furnace atomic absorption spectrometry (GFAAS) (also called electrothermal atomization [ETAAS]) is commonly used for sensitive elemental analysis. Following a summary of its principles, recent fundamental developments, and applications are reviewed. Advances in atomization mechanisms and instrumentation are discussed, followed by applications of speciation. New developments in direct solid sampling (SS) are reviewed that provide convenient, rapid, and green methodology. Novel preconcentration approaches are considered that provide reduced detection limits and removal of the sample matrix. A number of direct analyses are reviewed for clinical/pharmaceutical, food, environmental, and industrial samples. The conclusion discusses future developments in GFAAS, including the continued development of green protocols and speciation analyses. [ABSTRACT FROM AUTHOR]

In order to evaluate the effect of impact of the nature of solid fuel on performance indicators of a shaft melting furnace of the cupola type with an internal diameter of 2200 mm and a layer height of 4.5 m, and conditions for its oxidation, the real range of change in the properties of industrial coke batches of various manufacturers is determined (8 varieties) under conditions of non-oxidation heating of coke samples in an argon atmosphere at the rate of 5 deg/min to a temperature of 1000°C and isothermal exposure in an air atmosphere. Operating conditions of the mine unit on these cokes are evaluated with respect to values of specific coke consumption, mineral melt yield, thermal efficiency and changes in conditions for development of heat transfer from gases to materials based upon the ratio of heat capacities of their flows obtained from industrial tests. It is shown that an increase in the complete coke oxidation interval from 7 to 12.5 – 13.0 min will provide a decrease in specific coke consumption from 265 to 225 kg/ton of melt, i.e., by 15.9%, an increase in yield of mineral melt from 25.3 to 30.02%, i.e., by 18.66%, with a decrease in cupola total thermal efficiency from 61.7 to 60.2%, i.e., by 1,5%. For this it is advisable to use coke with maximum heat of combustion. Use of coke mineral raw material during melting, which has a rate of change of sample weight from 5.0 up to 8.0 – 8.5%/min (more active coke), provides a coke minimum specific consumption at the level of 224 kg/ton of melt with a maximum yield of molten smelting product of at least 29.8% of the weight of the initial components with unit thermal efficiency at 61.7%. For this it is necessary to use more active coke with respect to blast oxygen. Heat transfer process conditions from gases to materials during smelting are characterized by low intensity with the lowest ratio of heat capacities of material and gas flows not lower than 0.827 in the range of complete coke oxidation 12.5 – 13.0 min and an average rate of change in sample weight of about 6.0%/min. [ABSTRACT FROM AUTHOR]

Results obtained from rat studies indicate that, even at low concentrations, mercurial species cause harmful effects on the kidneys, by inducing the nephrotic oxidative stress response. In the present work, Hg-associated proteins were identified as possible mercury-exposure biomarkers in rat kidneys exposed to low mercury chloride concentrations for 30 days (Hg-30) and 60 days (Hg-60), using metalloproteomic strategies. The renal proteomic profile was fractioned by two-dimensional electrophoresis and the mercury determinations in kidney samples, protein pellets and protein spots were performed using graphite furnace atomic absorption spectrometry. The characterization of Hg-associated protein spots and the analysis of differentially expressed proteins were performed by liquid chromatography, coupled with tandem mass spectrometry. Eleven Hg-associated protein spots with a concentration range of 79 ± 1 to 750 ± 9 mg kg−1 in the Hg-60 group were identified. The characterization and expression analyses allowed the identification of 53 proteins that were expressed only in the Hg-60 group, 13 "upregulated" proteins (p > 0.95) and 47 "downregulated" proteins (p < 0.05). Actin isoforms and hemoglobin subunits were identified in protein spots of the Hg-60 group, with mercury concentrations in the range of 138 to 750 mg kg−1, which qualifies these proteins as potential mercury-exposure biomarkers. [ABSTRACT FROM AUTHOR]

A new direct immersion dual-drop microextraction (DIDDME) procedure is described for Fe(III) and Fe(II) speciation followed by detection with graphite furnace atomic absorption spectrometry. This method is based upon the selective reaction of 1-(2-pyridylazo)-2-naphthol (PAN) and N-benzoyl-N-phenylhydroxylamine (BPHA) with Fe(II) and Fe(III) to form complexes at pH 1.5. Two solvent drops that contain PAN and BPHA were concurrently immersed in a sample solution for simultaneous separation of Fe(III) and Fe(II), respectively. This method eliminated time-consuming and labor-intensive oxidation of Fe(II) or reduction of Fe(III), which may provide incomplete conversion and contamination. Using the optimal conditions, the detection limits were 0.067 ng mL−1 and 0.054 ng mL−1 for Fe(II) and Fe(III) with relative standard deviations of 6.0% and 5.1%, respectively. Enrichment factors of 300-fold were obtained. The procedure was successfully utilized for the determination of Fe(II) and Fe(III) in Chinese yellow wine. To evaluate accuracy of this method, a rice certified reference material was analyzed and the result was in good agreement with the certified value. [ABSTRACT FROM AUTHOR]

The study presents for the first time the figures of merit of a completely miniaturized instrumentation based on a capacitively coupled plasma microtorch as the core element interfaced with a small-sized electrothermal vaporization device and a low-resolution microspectrometer for the simultaneous determination of Cd, Pb, Cu and Zn by optical emission spectrometry in soil as total and labile fractions after diffusive gradients in thin-film (DGT) accumulation. The coupling of the low-power and low-argon consumption plasma (15 W; 150 mL min−1) with the DGT passive accumulation technique, although requiring a too-long time for sample preparation, allowed a considerable improvement of the detection limits and avoidance of the non-spectral matrix effects, otherwise a recognized process in low power microplasmas, when a complex matrix is analysed, like environmental samples. The detection limits for the total content in soil were (mg kg−1), 0.10(Cd), 0.40(Pb), 0.15(Cu), and 0.03(Zn), one order of magnitude better than in the procedure without DGT accumulation and 10–3300-times lower than the guide values in soil. In the DGT-based labile fraction exhibiting the highest bioavailability the detection limits were (μg kg−1) 0.01(Cd, Cu, and Zn) and 0.03(Pb), which allowed the determination of Cd, Pb, Cu and Zn in the concentration range (μg kg−1) of 0.3–2.0, 0.8–18.4, 2.4–56.3 and 9.4–60.6, respectively. Validation through the analysis of certified reference materials (CRMs) showed a recovery of 85–123% with a relative expanded uncertainty of 19–35% (k = 2) for the total content of analytes. The analysis of the certified reference materials highlighted that the DGT accumulation was not affected by the multielemental matrix, since the experimental diffusion coefficients of the analytes were similar in the four analyzed CRMs and to those provided by the manufacturer, respectively. Precision for the measurements of the total content and DGT-labile fraction in real samples evaluated from the combined uncertainty was 10–19% and 10–15%, respectively. The Bland–Altman plot applied to the results of real samples indicated the lack of statistical differences versus line-source graphite furnace atomic absorption spectrometry for both the total content and DGT-based labile fraction. [ABSTRACT FROM AUTHOR]

Breast cancer is characterized by the uncontrollable proliferation and dissemination of abnormal cells in the mammary glands. It is a significant cause of mortality among women, with approximately one in eight females experiencing a breast cancer diagnosis in their lifetime. Multiple factors contribute to an elevated risk of developing breast cancer, encompassing sex, lifestyle choices, age, hormone usage, familial predisposition and exposure to environmental pollutants. Environmental pollution refers to the contamination of various components of the Earth's atmosphere, biology and physical systems. Heavy metal pollutants include copper (Cu), cadmium (Cd), nickel (Ni), lead (Pb), zinc (Zn) and manganese (Mn). Exposure to toxic heavy metals through inhalation, skin contact and ingestion poses significant risks to human health and organ function, including the breasts. Essential heavy metals, such as Cu, Zn, cobalt (Co) and iron (Fe), play crucial roles in various biochemical and physiological processes within organisms. Various techniques have been employed to analyze heavy metals, including ultraviolet-visible spectrophotometry, inductively coupled plasma, flame atomic absorption spectrophotometry, graphite furnace atomic absorption spectroscopy, atomic emission spectroscopy and proton-induced X-ray emission. Recent studies have suggested an association between variations in heavy metal metabolism and the occurrence and progression of breast cancer in human populations. Some studies have found increased levels of Cu and Cd and decreased Zn and Mn concentrations in patients with breast cancer compared to individuals without breast cancer. The present review aimed to explore the link between heavy metal exposure and breast cancer, providing insight into its potential effects on breast health and the significance of this association. Overall, heavy metals directly affect human health, particularly as regards breast cancer. [ABSTRACT FROM AUTHOR]

Beryllium is an extremely toxic element for human beings. Therefore, knowledge of Be content in food samples is important to evaluating its potential effect on human health. The present study aimed to develop an efficient method for the quantification of Be in Chinese yellow rice wines. Samples were diluted with ultrapure water, and then directly analyzed by syringe membrane solid phase extraction (SMSPE) combined with graphite furnace atomic absorption spectrometry. TiO2@SiO2 flexible nanofiber membrane (TSFNFM) was used as the sorbent of SMSPE for enriching Be and eliminating matrices. Detection limit was 0.52 ng L-1 for Be with relative standard deviation of 6.4%. The linear range of calibration curve was in the range of 0.03-25 ng mL-1 with a correlation coefficient of 0.9946. An enrichment factor of 150 was obtained for Be. Two certified reference materials of tea leaves and rice were analyzed by this method, and the obtained results were in good agreement with certified values. The recoveries of spiking experiments were in the range of 90.0-110%. This method avoided the labor-intensive and time-consuming vortex/ultrasound and centrifugation/filtration steps, which may result in sample contamination and analysis errors. [ABSTRACT FROM AUTHOR]

Industrial activities in coastal areas can produce pollutant substances that are detrimental to the ecological environment. This study aimed to assess the ecological risks of heavy metal pollution in water, sediments, and polychaeta (Neoleanira tetragona) affected by aquaculture, urban rivers, and ports. Water parameters such as temperature, DO, pH, and salinity were measured in situ at fifteen observation stations. Samples were taken at three locations around the aquaculture area, namely the Barong River, the Musi River Estuary as an urban river area, and Tanjung Api-api port in South Sumatra, Indonesia. Analysis of sediment grain size and substrate types using the method of Shepard's triangle Heavy metal concentrations were measured by graphite furnace atomic absorption spectrometry. Then, the data were analyzed using one-way analysis of variance (ANOVA) and post-hoc Tukey statistical analysis. Ecological risk assessment uses the bioconcentration factor (BCF), index geoaccumulation (Igeo), contamination factor (Cf), and pollution load index (PLI). Based on the results, the concentration of heavy metal Pb in water was not detected until 0.625 mg/L, and Cu was not detected. Furthermore, Pb in sediments was 1.261-11.070 mg/kg, Cu was 0.193-19.300 mg/kg, Pb polychaeta was not detected until 0.0044 mg/kg, and Cu ranged from 0.0003-0.0014 mg/kg. Ecological risk assessment for BCF showed that the level of accumulation of polychaeta (N. tetragona) was categorized as an excluder (BCF < 1). Igeo and Cf indicate uncontaminated pollution levels (Igeo < 0) and low contamination (Cf < 1). Meanwhile, the Pollution Load Index is included in the nonpolluted category (PLI <0). Based on the results, the quality of the ecological environment affected by aquaculture, urban rivers, and ports is still classified as safe for ecological risk assessment; further studies are needed regarding the relationship between pollution levels and the physiological response of biota. [ABSTRACT FROM AUTHOR]

Copyright of Bistua: Revista de la Facultad de Ciencias Básicas is the property of Facultad de Ciencias Basicas de la Universidad de Pamplona and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Longyan City in Fujian Province is one of China's top-quality tobacco-producing areas and plays an essential role in local economic development. To determine the correlation between heavy metal content in tobacco leaves and soil factors, soil physical and chemical properties and heavy metal contents of lead, cadmium, and copper in tobacco leaves were measured and analyzed by the correlation regression method. The content of lead, cadmium, and copper in soil was determined using hydrochloric acid extraction-AAS and graphite furnace atomic absorption spectrometry. Inductively coupled plasma-mass spectrometry was used to determine heavy metal in tobacco leaf. The findings revealed that the average concentrations of lead, cadmium, and copper in the soil were 12.1, 0.092, and 3.88 mg/kg, respectively. In contrast, the average levels of lead, cadmium, and copper in tobacco leaves were 2.33, 4.89, and 4.35 mg/kg, respectively. The cadmium enrichment coefficient of 54.3 was higher than lead and copper, indicating a greater health risk. Soil pH value was negatively correlated with lead content in tobacco leaf, while potassium and phosphorus nutrient levels were negatively correlated with copper content. In contrast, a positive correlation was established between the presence of organic matter with cadmium content in tobacco leaves. The prediction models of lead, cadmium, and copper in tobacco leaves can be expressed by the regression equation corresponding to each heavy metal as follows: Y Pb = 2.33 − 0.005 ∗ X K + 0.007 ∗ X N − 0.271 ∗ X pH + 0.065 ∗ X Pb ( R 2 = 0.787), Y Cd = 1.55 + 0.012 ∗ X OM − 0.014 ∗ X Cu + 34.6 ∗ X Cd ( R 2 = 0.891), and Y Cu = 4.64 − 0.029 ∗ X P − 0.007 ∗ X K + 0.245 ∗ X Cu ( R 2 = 0.724), respectively. The prediction models above provide an effective predictive tool for assessing heavy metal risk in tobacco leaves using soil properties in the study area. [ABSTRACT FROM AUTHOR]

In this study, the trace elements lead (Pb), arsenic (As), cadmium (Cd), nickel (Ni), copper (Cu), zinc (Zn) and iron (Fe) quantity have been investigated using graphite furnace atomic absorption spectrometry (GFAAS) and sulphur dioxide (SO2) residual by iodometric titration method in raisin samples in different regions of Iran. The results showed that the concentration of Cu, Zn and Fe were in the range of 0.053–0.212 mg/kg, 0.048–0.170 mg/kg and 0.541–0.843 mg/kg, respectively, whereas Cd, Ni, As and Pb concentrations in the samples were less than detection limit (LOD). The SO2 residual in raisin samples was between 30 and 843.33 mg/kg. The LOD of Cu, Fe, Zn, Cd, Pb, Ni, and As were 0.022 mg/kg, 0.5 mg/kg, 0.047 mg/kg, 0.04 mg/kg, 0.019 mg/kg, 0.024 mg/kg and 0.05 mg/kg, respectively. The Monte Carlo simulation results showed that the indexes of target hazard quotient (THQ) due to ingestion of SO2 residues estimated lower than the safe level (THQ < 1) in all samples, except in the Raisin-B and Raisin-D samples. Accordingly, to ensure consumer health and improve international trade, continuous control and adaptive regulation of sulphur dioxide residues and trace elements in dried fruit are recommended. [ABSTRACT FROM AUTHOR]

The ion-imprinted polymer combined with the solidification of floating organic drop microextraction has been developed as an ultra-pre-concentration technique to determine lead ions in real samples. In ion-imprinted polymer – solidification of floating organic drop microextraction, lead was adsorbed from a large volume of aqueous samples (500 mL) into 100 mg of the ion-imprinted polymer sorbent. After the elution of lead ions from the sorbent by using nitric acid, the solidification of floating organic drop microextraction technique was performed on the obtained solution. Several important extraction parameters, such as weight of ion-imprinted polymer (mg), pH, uptake time (min), desorption time (min), HNO3 desorption volume (mL) aqueous-phase volume (mL), were studied and optimised. The ion–imprinted polymer particles were characterised by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). The new method (SPE–SFODME) provided an ultra-enrichment factor (5000) for lead. The calibration graphs were linear in the range of 5–200 ng L−1. The optimum conditions for the method were as follows: pH of solution, 7.5; weight of ion-imprinted polymer, 100 mg; type and concentration of eluent, HNO3 1 M; volume of eluent, 1 mL; sorption time, 25 min; desorption time, 15 min. Under optimum conditions, the limit of detection (LOD) was 1 ng L−1 for lead and relative standard deviation (RSD %) for five replicate determinations of 10 ng L−1 for lead was 6.5%. The results for the determination of lead ions in reference materials, tap water, ground vegetables, butter and flour wheat demonstrated the accuracy, recovery and applicability of the presented method. [ABSTRACT FROM AUTHOR]

The study aims to compare different approaches and efficacies during the biological production of nanoparticles (NPs). Gold nanoparticles (AuNPs) are produced by Fusarium oxysporum at two different temperatures. One flask is incubated at 37 °C ("Common") and the other is directly heated for 5 min at 80 °C ("Heat‐treated"). Obtained AuNPs are analyzed and compared by spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDS), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). Graphite furnace atomic absorption spectroscopy (GF‐AAS) is used to determine the particle concentration after the AuNPs production. The AuNPs prepared by both (the Common and the Heat‐treated) methods exhibit maximum absorption peaks at 541 and 528 nm, respectively, and have round shapes and sizes of less than 50 nm. Their zeta potential is about −28 mV. GF‐AAS shows that the efficiency of AuNP production in Common‐ and Heat‐treated samples is equal, between 65% and 68%. Since the Heat‐treated sample shows a better size distribution, the use of higher temperature and shorter time period is preferable for the bioproduction of AuNPs. It seems that shortening the time for the production of AuNPs prevents the formation of larger NPs. [ABSTRACT FROM AUTHOR]

Salty areas "Chotts" are very common in the South Highlands of Setif Governorate (northeast of Algeria). In fact, a large part of the sheep population is eventually driven to graze in these areas. However, there is no data on the mineral status of these sheep or on the mineral content of the water and fodder they consume. The present study aims to compare the plasmatic ionogram profiles of Ouled Djellal ewes reared in the Setif Highlands according to feed and water salinity. For this purpose, twenty healthy ewes, aged 2 to 3 years, were selected randomly from two semi-extensive flocks, reared in two distant regions, where they are fed exclusively with locally produced straw, and watered using water with different saltiness levels: sulfated water (S) and soft water (T). Plasmatic concentrations of macroelements (Calcium "Ca", Phosphorus "P", Magnesium "Mg", Sodium "Na", Potassium "K") and trace elements (Iron "Fe", Copper "Cu", Zinc "Zn", and Manganese "Mn") were monitored monthly for one year. Ca, P, Mg, and Fe plasmatic levels were measured using a spectrophotometer, while Na and K levels were measured using flame spectrometry. The plasmatic Cu, Zn and Mn levels were measured using Graphite furnace atomic absorption spectroscopy. Results showed that plasmatic values of mineral macro elements change within standard normal ranges, with values slightly higher in Oum Ladjoul region, where the water is sulfated. Regarding the trace elements, sheep of Oum Ladjoul region were not deficient in Cu and Fe, compared to sheep of the witness region (Smara, El-Eulma). The plasmatic Zn levels were low in both regions with regard to the species norms. The absorption of sulfated water (S) seems to have a positive effect on the plasmatic level of the studied minerals. Overall, the consumed water in the study region does not seem to have an undesirable influence on the mineral metabolism. Further investigation is needed to understand the effects of drinking water at different physiological stages and over the long term in the study region. [ABSTRACT FROM AUTHOR]

Because China produces the most crayfish in the world, safe solutions must be improved to mitigate the risks of ongoing heavy metal stressors accumulation. This study aimed to use Saccharomyces cerevisiae as a bioremediation agent to counteract the harmful effect of cadmium (Cd) on crayfish (Procambarus clarkia). Our study used three concentrations of S. cerevisiae on crayfish feed to assess their Cd toxicity remediation effect by measuring total antioxidant capacity (TAC) and the biomarkers related to oxidative stress like malondialdehyde (MDA), protein carbonyl derivates (PCO), and DNA–protein crosslink (DPC). A graphite furnace atomic absorption spectroscopy device was used to determine Cd contents in crayfish. Furthermore, the mRNA expression levels of lysozyme (LSZ), metallothionein (MT), and prophenoloxidase (proPO) were evaluated before and following the addition of S. cerevisiae. The results indicated that S. cerevisae at 5% supplemented in fundamental feed exhibited the best removal effect, and Cd removal rates at days 4th, 8th, 12th, and 21st were 12, 19, 29.7, and 66.45%, respectively, which were significantly higher than the basal diet of crayfish. The addition of S. cerevisiae increased TAC levels. On the other hand, it decreased MDA, PCO, and DPC, which had risen due to Cd exposure. Furthermore, it increased the expression of proPO, which was reduced by Cd exposure, and decreased the expression of LSZ and MT, acting in the opposite direction of Cd exposure alone. These findings demonstrated that feeding S. cerevisiae effectively reduces the Cd from crayfish and could be used to develop Cd-free crayfish-based foods. [ABSTRACT FROM AUTHOR]

Human exposure to acute and chronic levels of heavy metal ions are linked with various health issues, including reduced children's intelligence quotients, developmental challenges, cancers, hypertension, immune system compromises, cytotoxicity, oxidative cellular damage, and neurological disorders, among other health challenges. The potential environmental HMI contaminations, the biomagnification of heavy metal ions along food chains, and the associated risk factors of heavy metal ions on public health safety are a global concern of top priority. Hence, developing low-cost analytical protocols capable of rapid, selective, sensitive, and accurate detection of heavy metal ions in environmental samples and consumable products is of global public health interest. Conventional flame atomic absorption spectroscopy, graphite furnace atomic absorption spectroscopy, atomic emission spectroscopy, inductively coupled plasma–optical emission spectroscopy, inductively coupled plasma–mass spectroscopy, X-ray diffractometry, and X-ray fluorescence have been well-developed for HMIs and trace element analysis with excellent but varying degrees of sensitivity, selectivity, and accuracy. In addition to high instrumental running and maintenance costs and specialized personnel training, these instruments are not portable, limiting their practicality for on-demand, in situ, field study, or point-of-need HMI detection. Increases in the use of electrochemical and colorimetric techniques for heavy metal ion detections arise because of portable instrumentation, high sensitivity and selectivity, cost-effectiveness, small size requirements, rapidity, and visual detection of colorimetric nanosensors that facilitate on-demand, in situ, and field heavy metal ion detections. This review highlights the new approach to low-cost, rapid, selective, sensitive, and accurate detection of heavy metal ions in ecosystems (soil, water, air) and consumable products. Specifically, the review highlights low-cost, portable, and recent advances in smartphone-operated screen-printed electrodes (SPEs), plastic chip SPES, and carbon fiber paper-based nanosensors for environmental heavy metal ion detection. In addition, the review highlights recent advances in colorimetric nanosensors for heavy metal ion detection requirements. The review provides the advantages of electrochemical and optical nanosensors over the conventional methods of HMI analyses. The review further provides in-depth coverage of the detection of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) ions in the ecosystem, with emphasis on environmental and biological samples. In addition, the review discusses the advantages and challenges of the current electrochemical and colorimetric nanosensors protocol for heavy metal ion detection. It provides insight into the future directions in the use of the electrochemical and colorimetric nanosensors protocol for heavy metal ion detection. [ABSTRACT FROM AUTHOR]

Through multiple different pathways, the environmental multiple metals make their ways to the human bodies, where they induce different levels of the oxidative stress response. This study further investigated the impact of multiple-metal exposure on the risk of developing proliferative diabetic retinopathy (PDR). We designed a case–control study with type 2 diabetic patients (T2D), in which the case group was the proliferative diabetic retinopathy group (PDR group), while the control group was the non-diabetic retinopathy group (NDR group). Graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to detect the metal levels in our participants' urine samples. The least absolute shrinkage and selection operator (LASSO) regression approach was used to include these representative trace elements in a multiple exposure model. Following that, logistic regression models and Bayesian kernel machine regression (BKMR) models were used to describe the effect of different elements and also analyze their combined effect. In the single-element model, we discovered that lithium (Li), cadmium (Cd), and strontium (Sr) were all positively related to PDR. The multiple-exposure model revealed a positive relationship between Li and PDR risk, with a maximum quartile OR of 2.80 (95% CI: 1.10–7.16). The BKMR model also revealed that selenium (Se) might act as a protective agent, whereas magnesium (Mg), Li, and Cd may raise the risk of PDR. In conclusion, our study not only revealed an association between exposure to multiple metals and PDR risk but it also implied that urine samples might be a useful tool to assess PDR risk. [ABSTRACT FROM AUTHOR]

A novel modified carbon paste electrode has been developed using a laboratory synthesized metal chelating ligand (L), N1‐hydroxy‐N1,N2‐diphenylbenzamidine (HDPBA) and multi‐walled carbon nanotubes (MWCNTs) composite (L‐MWCNTs/CPE). The developed modified electrode was applied for selective and sensitive simultaneous electrochemical determination of cadmium(II), lead(II), and mercury(II) using square wave anodic stripping voltammetry (SWASV). The accumulation of metal ions on the electrode surface was performed in 0.1 M acetate buffer solution (ABS, pH 5.0) by applying a potential of–1.10 V versus Ag/AgCl for 210 s, followed by stripping in the positive potential scan of the SWASV after a rest time of 10 s. Under the optimum experimental conditions, the linear dynamic ranges were found to be 2×10−4–2, 1×10−4–2 and 2×10−3–2 μM of cadmium(II), lead(II), and mercury(II), respectively, with the detection limits (LODs) of 2.5×10−2, 7.8×10−3 and 4.6×10−1 nM for cadmium(II), lead(II), and mercury(II), respectively. The proposed electrode exhibited high sensitivity for the determination of these metal ions with excellent reproducibility and stability. The influence of several ions on the simultaneous determination of Cd(II), Pb(II), and Hg(II) was studied, and the prepared electrode was found to be highly selective for the detection of the three metal ions. The developed electrode was effectively applied to the determination of the three metal ions in water, vegetable and tobacco samples, and the obtained results were similar to those measured with graphite furnace atomic absorption spectrometry (GFAAS). [ABSTRACT FROM AUTHOR]

This study aimed to determine aluminum (Al) contents in commonly consumed noodles and estimate the risk of Al exposure through the consumption of noodles in the Thai population. A total of 80 samples, 20 samples each of rice stick noodles, egg noodles, wide rice noodles, and Thai rice noodles was purchased from markets in Bangkok Metropolitan and other four provinces in each region of Thailand. Wet digestion and graphite furnace atomic absorption spectrometry (GFAAS) were used to determine Al contents. Exposure assessment of Al was conducted by applying the consumption amounts of noodles from the national consumption survey and the Al contents of the noodle samples. The hazard quotient (HQ) was calculated to estimate the risk of exposure to Al. Aluminum contents in the noodles ranged from not detected to 630 mg/kg. Exposure to Al from consumption of each noodle product in all age groups was lower than the provisional tolerable weekly intake (PTWI). However, Al exposures in children calculated from the high consumer models and Al exposures in all age groups from the worst-case scenarios were higher than the PTWI, indicating potential adverse health effects. Consumers who regularly consume large amounts of noodle products containing Al may be at risk of having adverse health effects. [ABSTRACT FROM AUTHOR]

In view of the relevance of urban parks and public squares to the well-being of the population, coupled with the presence of uraniferous phosphorite in the Metropolitan Region of Recife, State of Pernambuco, Brazil, this study aimed to evaluate the contribution of natural radionuclides and the toxic chemical elements As, Cd, Ni, Pb, and Sb found in the soils of urban green spaces to the population's carcinogenic risks. Samples consisting of soils collected from a depth of 0–15 cm were analyzed by High Resolution Gamma Spectrometry, Graphite Furnace Atomic Absorption Spectrometry and Inductively Coupled Plasma Mass Spectrometry, after chemical treatment. The annual effective dose rates were estimated to be lower than the threshold for individual exposure to ionizing radiation of 1 mSv year−1, even in green spaces close to uraniferous outcrops. There were As, Cd, Ni, and Pb hotspots in these soils, resulting in high values of Pollution Load Index (PLI) for practically all the studied green spaces. Although considerable non-carcinogenic risks were not found, two green spaces presented significant carcinogenic risks for adults. Furthermore, significant carcinogenic risks would be expected for children at all study sites. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Medicinal plants growing in geothermal areas have been reported to possess relatively high abundance of bioactive secondary metabolites concomittant to the adaptive heat stress response. Nonetheless, the exploitation of their medicinal benefits is limited by the possible healththreatening concentrations of heavy metal contamination. Chromolaena odorata Linn, or also called as seurapoh, is a well-known medicinal plant but could absorb and accumulate heavy metal from the soil. Herein, this present study aimed to investigate the contents of Hg, Pb, Cd, and As in ethanolic extract of Chromolaena odorata Linn leaves collected from a geothermal area in Aceh of Indonesia. METHODS: Three hot springs (Ie-Suum, Ie-Jue, and Ie-Brouk) located in the same geothermal area Seulawah Agam was selected as the sampling points, where three samples of Chromolaena odorata were collected in each sampling point. Extraction was carried out by means of maceration employing ethanol solvent. The contents of heavy metals in each extract were determined by priorly validated atomic absoption spectrometry and graphite furnace atomic absorption. FINDINGS: The results revealed that arsenic (0.0482 ± 0.004 - 0.0639 ± 0.007 miligram per kilogram) and lead (0.0219 ± 0.004 - 0.0672 ± 0.006 miligram per kilogram) were found in trace levels and did not exceed Indonesian maximum safety thresholds (=5 and =10 miligram per kilogram, respectively). The presence of mercury in all samples was not observable (limit of detection= 0.018 miligram per liter). Cadmium was observed in almost all samples with a concentration range of 0.0219 ± 0.005 - 1.1472 ± 0.006 miligram per kilogram exceeding the maximum threshold (0.3 miligram per liter). CONCLUSION: Contamination of heavy metals in the ethanolic extract of geothermal Chromolaena odorata leaves is thought to be originated from volcanic activities. Among the heavy metals of concern, cadmium was the only one with concentration exceeding the safety limit. The presence of cadmium in the extract with high concentration could act cause its translocation to human body which eventually lead to multiple organ damages. Therefore, the extract of geothermal C. odorata leaves collected from a geothermal area should be consumed with caution for possible cadmium intoxication. [ABSTRACT FROM AUTHOR]

In this study, gold nanoparticles produced by eukaryotic cell waste (AuNP), were analyzed as a transfection tool. AuNP were produced by Fusarium oxysporum and analyzed by spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS) were used before and after conjugation with different nucleic acid (NA) types. Graphite furnace atomic absorption spectroscopy (GF-AAS) was used to determine the AuNP concentration. Conjugation was detected by electrophoresis. Confocal microscopy and quantitative real-time PCR (qPCR) were used to assess transfection. TEM, SEM, and EDS showed 25 nm AuNP with round shape. The amount of AuNP was 3.75 ± 0.2 µg/µL and FTIR proved conjugation of all NA types to AuNP. All the samples had a negative charge of − 36 to − 46 mV. Confocal microscopy confirmed internalization of the ssRNA-AuNP into eukaryotic cells and qPCR confirmed release and activity of carried RNA. [ABSTRACT FROM AUTHOR]

Copyright of CULCyT: Cultura Científica y Tecnológica is the property of Cultura Cientifica y Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The generalized Born (GB) model is a fast implicit solvent model that is used as an approximation to the Poisson equation for solutes described by point charges. Due to the simple analytical form, GB models are widely used in molecular dynamics simulations to account for (implicit) solvation effects. In this work, we extend the application of the GB model to polarizable charges by coupling it to the bond capacity (BC) model. The resulting BC–GB model is a non-variational polarization model where the reaction potential is calculated from a GB expression and included in the polarization equation to account for solvation effects. Being non-variational, the BC–GB makes use of a Lagrange formulation for an efficient evaluation of energy gradients. The stability of the algorithm in molecular dynamics simulations is tested in the microcanonical ensemble, and the results show energy conservation as well as small fluctuations. The inclusion of implicit solvation increases the computational cost by only 15% compared to vacuum. Combined with a significant reduction in system size by describing the solvent as a continuum makes the BC–GB model an interesting model for applications requiring the combination of solute polarization and extensive conformational space sampling. [ABSTRACT FROM AUTHOR]

The broadband photoelectron source realized by detaching O2−·X (X = neutral unsaturated molecule) complexes offers a unique opportunity to probe temporary anion states of the unsaturated species. Detachment of the ion molecule complex typically accesses a dissociative portion of the neutral potential, creating a continuum electron source that can undergo scattering with X. We present the application of this new approach to electron-neutral scattering toward a study of the series of fluorinated benzenes via photoelectron spectroscopy of O2−·C6H6−xFx (x = 0–6) measured with several photon energies. We compare these spectra to the reference O2−·hexane spectrum and observe evidence of temporary anion states of C6H6−xFx for species with x = 0–5 in the form of enhanced signal intensity at electron kinetic energies coinciding with the energies of the temporary anions. Furthermore, we observe autodetachment features in the x = 3, 5 spectra. Results of calculations on the isolated symmetric isomer of C6H3F3 suggest that the molecule cannot support a weakly-bound non-valence state that could be associated with the observed autodetachment. However, C6HF5− is predicted to support a valence bound state, which, if produced by charge transfer from O2− with sufficient vibrational energy, may undergo autodetachment. Finally, the [O2·C6F6]− spectrum is unique insofar as the spectrum is substantially higher in binding energy and qualitatively different from the x = 0–5 spectra. This result suggests much stronger interactions and charge delocalization between O2− and C6F6. [ABSTRACT FROM AUTHOR]

The initial stages of particle formation are important in several industrial and environmental systems; however, the phenomenon is not completely understood due to the inability to measure cluster size distributions. A high resolution differential mobility analyzer with an electrometer was used to map out the early stages of Si particle formation from pyrolysis of SiH4 in a furnace aerosol reactor. We detected for the first time subnanometer stable clusters from silane pyrolysis, and the diameter was measured to be about 0.7 nm. This diameter is within the range of probable sizes that the reported families of critical silane clusters could have based on their actual molecular structure. The size distributions of negative clusters are also mapped out. In addition, gas chromatography mass spectrometry, and transmission electron microscopy characterizations of the clusters and primary particles are used to assess their mechanistic roles in aerosol dynamics of the initial stages of particle formation. [ABSTRACT FROM AUTHOR]