Graphite Furnace Research Articles

A straightforward deep eutectic solvent-based extraction for the determination of lead in drill cuttings by graphite furnace atomic absorption spectrometry

A straightforward deep eutectic solvent-based extraction for the determination of lead in drill cuttings by graphite furnace atomic absorption spectrometry

Assessment of potential health risks associated with heavy metal concentrations in leafy vegetables in Kerman, Iran

ABSTRACT Despite the growing awareness of the nutritional benefits of leafy vegetables, there is a lack of information about the presence of heavy metals and the associated risks in these products. This study aimed to investigate the concentration of heavy metals in leafy vegetables in Kerman City. The research also assessed the intake of heavy metals and the associated drisks for children and adults who consume these vegetables. The study followed the recommended methods by the US Environmental Protection Agency (USEPA) to evaluate both carcinogenic and non-carcinogenic diseases. A total of 400 leafy vegetable samples, including parsley, coriander, Persian leek, and basil, were randomly collected from agricultural farms in the outskirts of Kerman City. The samples were analysed using a graphite furnace atomic absorption spectrometer to measure the concentrations of lead (Pb), cadmium (Cd), iron (Fe), and copper(Cu). The results revealed that the levels of heavy metals in leafy vegetable samples exceeded the recommended standards set by international organisations such as FAO/WHO, European countries, and Iran. The total target hazard quotient (THQ) for non-carcinogenic diseases resulting from the consumption of leafy vegetables was higher than one for both children and adults in all studied areas, indicating a potential risk of non-carcinogenic diseases associated with the consumption of these vegetables. Furthermore, the average Incremental Lifetime Cancer Risk (ILCR) resulting from exposure to agricultural soil through leafy vegetable consumption exceeded the hazardous and unacceptable range of 104− × 10−6 in both children and adults. This suggests the possibility of carcinogenic diseases caused by Pb and Cd through the consumption of leafy vegetables in all studied areas, with a higher overall risk observed in children compared to adults. In conclusion, while leafy vegetables are widely recognised for their nutritional benefits, our study underscores a critical gap in understanding the presence of heavy metals and the associated risks in these products. The findings reveal that the concentrations of heavy metals in leafy vegetables from Kerman City exceed international standards, posing potential health risks, particularly in children. Further research and regulatory actions are warranted to address this pressing issue and ensure the safety of our food supply.

Phytochemical Characterization, Antioxidant, and Antimicrobial Activity of the Vegetative Buds from Romanian Spruce, Picea abies (L.) H. Karst.

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.

Assessing Metal Exposure and Leaching from Discarded Cigarette Butts: Environmental Analysis and Integrated Waste Management Approaches.

Cigarette butts, often discarded as litter, are considered a common form of waste, containing a variety of pollutants within this hazardous residue. This study, which was designed to assess the environmental release of certain metals from cigarette butts, investigates a variety of scenarios under varying climatic conditions. Thus, in order to assess the level of metal contamination, samples of cigarette butts were collected in urban areas from seven popular brands in China, smoked artificially, and examined through graphite furnace atomic absorption (GF-AAS). The findings indicated mean concentrations of 1.77 for Cr, 2.88 for Ni, 12.93 for Cu, 24.25 for Zn, and 1.77 µg/g for Pb in the case of newly smoked butts. The emission of each of the metals increases to 8-10% when cigarette butts remain in the environment for an extended period of time. Furthermore, rainfall can accelerate metal leaching, reaching values of 18-20% compared to the controlled scenario. The worst-case scenario releases 2129.31 kg/year of metals into the environment, while the best-case scenario sees a lower release of 844.97 kg/year. The data reflect variations in metal emissions across different scenarios. There was also a strong correlation between cigarette butts in public spaces and cities. This research highlights the need to educate smokers and increase urban maintenance efficiency to reduce this litter and the metals it leaches into the environment.

Rapid and sensitive determination of trace Cd in carbonate samples using direct solid sampling electrothermal vaporization atomic absorption spectrometry

The accurate determination of cadmium (Cd) hosted and accumulated in sedimentary carbonate remains challenging due to its low concentration (ng·g−1) and complex matrix. Conventional methods, such as inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GF-AAS), which typically rely on liquid sampling and sample digestion, are tedious, labor-intensive and time-consuming. In this study, a rapid and sensitive method for the direct determination of carbonate-hosted Cd was developed based on solid sampling electrothermal atomic absorption spectrometry (SS-ETV-AAS). This method eliminates the need of acid digestion procedure, allowing the entire analysis, including sample preparation, to be completed within 10 min. To minimize the carbonate matrix effect, ethylene diamine tetra acetic acid disodium salt (EDTA-2Na) was proposed as matrix modifier to facilitate the release of Cd, enabling fast and accurate determination of trace Cd in carbonate samples. Under optimized conditions, the Cd detection limits was found to be as low as 0.17 ng·g−1, and repeatability (relative standard deviation, RSD) was better than 8 % (n = 7). The accuracy of the proposed SS-ETV-AAS was verified by analyzing five carbonate certified reference materials (GBW07127, GBW07129, GBW07130, GBW07135 and JDo-1), two soil certified reference materials (GBW07404a, GBW07405), as well as several actual carbonate samples. All these results demonstrate that the proposed SS-ETV-AAS method provides a simple, rapid and sensitive approach for measuring trace Cd in carbonates.

Health and ecological risk assessment of heavy metals in water and sediments within a data scarce urban catchment in Tanzania – A case of Ngerengere River, Morogoro Municipality

Low-, middle- and high-income countries, exhibit indications of risks associated with water quality. The study investigated heavy metal concentrations in surface water and sediments within the Ngerengere River and its tributaries (Kikundi, Bigwa, and Morogoro) drain within in the Morogoro Municipality of Tanzania, an Urban Catchment Area (UCA) with limited available data mainly because of inadequate monitoring and reporting capabilities. Analysis of health and ecological risks associated with heavy metal pollution was also carried out using health risk assessments models, pollution indices, and multivariate analysis techniques. Between the dry and wet seasons of 2023, water and sediment samples from (13) sampling stations strategically established along the Ngerengere river and its tributaries were analyzed for six heavy metals (Pb, Cr, Ni, Cd, Cu and Zn) using the Atomic Absorption Spectrophotometer Model Perking Elmer 850 Graphite Furnace and Perking Elmer AS 800 Auto-sampler coupled with a computer interface for operational, displaying and reading the results. The calculated degree of water contamination (Cd) values in river water in both dry and wet seasons ranged from 0 to 6.803 indicating low and high degrees of contamination respectively. Heavy metal concentration in sediment decreases in the order of Zn>Ni>Cr>Cu>Cd>Pb. The non-cancer risk index (HI) via ingestion and dermal pathways in dry and wet seasons for both children and adult groups was <1 hence no non-cancer risk, However, cumulative dermal and ingestion exposure in both children and adults indicated potential cancer risk in dry and wet season. The analysis of ecological risks associated with heavy metal enrichment in the sediment indicated high enrichment of sediments with Cd, Ni and Zn. Conclusively, in wet months, risk indices tend to be low, while in dry months, they typically remain high.

Evaluation of imprecision in the different detection methods of Zn based on 5 years of data from an external quality assessment program in China

BackgroundThis study examines the imprecision of zinc (Zn) measurements across various clinical detection methods by analyzing the external quality assessment (EQA) data from 2018 to 2022. The findings of this study aim to offer recommendations for enhancing Zn measurements. MethodsParticipating laboratories were grouped into peer categories based on the detection methods. The robust mean and coefficient of variation (CV) of the samples were calculated following ISO 13528 guidelines. The evaluation criteria for optimal, desirable, and minimum allowable imprecision in Zn estimation are 2.50%, 5.05%, and 7.55%, respectively, based on biological variation. Furthermore, the study examined inter-lab CVs, inter-method bias, and the passing rate. The impact of sample concentration on CVs and the pass rate was also investigated. ResultsOver the past five years, 4283 laboratories participated in the EQA program, showing a high pass rate that improved as sample concentration increased. Differential pulse polarography (DPP) demonstrated stable and low CVs (0.61–1.86%). Although differential pulse stripping (DPS) was less stable than DPP, it still exhibited a low CV (0.71–3.10%). Graphite furnace atomic absorption spectrometry (GFAAS) and flame atomic absorption spectrometry (FAAS) performed similarly and displayed stable CVs (2.39–4.42%) within the acceptable range of desirable imprecision (5.05%). However, the CVs for ICP-MS were unacceptable in three out of the five years (5.28–6.20%). In 2022, the number of participating laboratories for DDP, DPS, GFAAS, FAAS and ICP-MS is 131, 35, 35, 820 and 72, respectively. ConclusionThis study provides reliable insights into the imprecision of Zn measurements in clinical laboratories. The findings indicate that additional efforts are required to reduce the imprecision of ICP-MS in Zn measurements.

Insights into the thermal and electric field distribution and the structural optimization in the graphitization furnace

The Acheson graphitization furnace (AGF), as a most energy-consuming equipment for graphite production, results in substantial thermoelectric losses during heating process. To improve the thermal efficiency, a method is proposed to optimize the structure of furnace core based on the thermoelectric field distribution. In this study, a numerical simulation using FLUENT software was adopted to explore the characteristics and coupling rules in relation to thermoelectric field distribution. Further optimize furnace core structure to achieve more suitable performance indicators, which include electrical heating efficiency and thermal efficiency. The results suggested that the changes of electric (power density) and thermal (temperature) fields with the layout of coke materials exhibited a consistence: the lower power density and temperature were observed at the position of graphitized coke, while the higher values were for calcined coke. The heat producer during the graphitization process was twofold: the electric heat and the transferred heat, and their proportion was confirmed as a range of 7:3–9:1. Under a fixed square side section, which is an optimal scenario, both thermal efficiency and electric heating efficiency with the furnace core length presented a parabolic variation. These findings may provide some guidelines and insights for a better design and operation of AGFs.

A Cross-Sectional Analysis Investigating Pregnant Women's Renal Function and Its Association with Lead and Cadmium Exposures-The DSAN Birth Cohort Study in Recôncavo Baiano, Brazil.

Kidney dysfunction is increasing worldwide and is exacerbated by exposure to toxic metals. Also, pregnancy poses an overload on kidney function. We investigated how blood lead (PbB) and cadmium (CdB) levels were associated with kidney function in pregnant women from Recôncavo Baiano, Brazil, during their second trimester. In this cross-sectional study, the estimated glomerular filtration rate (eGFR) was calculated from serum creatinine and whole blood metal levels were measured by graphite furnace atomic absorption spectrophotometry in 136 volunteers. Sociodemographic data were collected using semi-structured questionnaires. The medians (IQR) of PbB, CdB, and eGFR were 0.85 µg/dL (0.45-1.75), 0.55 µg/L (0.08-0.91), and 121.8 mL/min/1.73 m2 (106.0-127.9), respectively. PbB medians were significantly higher in the eGFR < 90 group at 2.00 µg/dL (0.83, 3.10). After age-adjusted logistic regression, pregnant women with elevated PbB levels had decreased eGFR (OR = 1.82; 95%-CI, 1.14-3.14). However, the participants with elevated PbB levels who reported consuming alcohol during pregnancy or had CdB in the highest tertile had higher odds of reduced eGFR (OR = 2.44; 95%-CI, 1.30-5.47) and (OR = 11.22; 95% CI, 2.53-103.51), respectively. These results suggest that low Pb exposure may affect kidney function in pregnant women and calls for further investigation into toxic metal co-exposures on kidney function during pregnancy in at-risk communities.

The Determination and evaluation of trace elements in the blood of radiography workers using graphite furnace atomic absorption spectrometry

This study aimed to evaluate the potentially toxic effects of trace elements in the blood of Iraqi medical radiography workers by analyzing them through GF-AAS. The study involved 50 male blood radiography workers from the medical imaging field at Al-Shatrah General Hospital in Thi-Qar City, Iraq. All workers were aged between 35-50 years and had worked for less than 10 years. The study compared these workers with 50 healthy men. The study found a significant increase in the levels of Cu, Pb, Cd, and Ca among radiography workers compared to the healthy control group, while Zn and Se levels decreased significantly. Moreover, Specificity and confidence interval (95%) were estimated via the receiver operating characteristic curve (ROC). The study provided conclusive evidence of disturbances in the levels of trace elements in the blood of radiographer workers, which makes them more susceptible to many diseases because of their radiation exposure. which portends the more preventive measures of radiation. The linear range of Cd, Cu, Zn, Se and Pb in human serum were obtained 0.2-6.0 µg dL-1, 6.0-200 µg dL-1, 8.0-200 µg dL-1, 10-250 µg dL-1, 4-120 µg dL-1 by GF-AAS after dilution samples with DW up to 20 (n=10, RSD&lt; 5%).

A new method based on extraction induced by emulsion breaking for determination of Co and Ni in chocolate bars by graphite furnace atomic absorption spectrometry

This paper describes a new experimental configuration of extraction induced by emulsion breaking method to extract and determine Ni and Co in chocolate bars by graphite furnace atomic absorption spectrometry. At optimized conditions, the sample (0.08 g) was mixed with 4 mL of extractant solution (4% m/v Triton X-100 and 10% v/v HNO3) in a plastic syringe to form a solid-oil-water emulsion. Then, emulsion breaking was assisted by membrane filtration. The total extraction procedure took approximately 1 min, in opposition to 25 (centrifugation) and 50 min (heating). Extraction yields ranged from 94.8 to 114.3% for Co and from 85.9 to 108.4% for Ni. The limits of detection and quantification were, respectively, 24.73 and 82.45 μg Kg−1 for Co and 49.05 and 163.5 μg Kg−1 for Ni. Recoveries ranged from 92.1 (Ni) to 105.4% (Co).

Use of ceramic fiber modified with ferrites for the cleaning of flue gases of graphitization furnaces

Gaseous emissions of industrial enterprises as a result of their economic activities adversely affect the ecological situation, and even worsen the sanitary and hygienic working conditions of the personnel. Carrying out chemical reactions in the furnace equipment of metallurgical and electrothermal production, as a rule, lead to the formation of gases containing various toxic impurities, including carbon monoxide, the disposal of which is an important environmental task. As the calculations show, the total amount of annual CO emissions in Ukraine is 704344.218 t/year, which in percentage terms is 31.42% of the total emissions of pollutants and greenhouse gases, except for carbon dioxide - 2242020.75 t/year. The release of significant amounts of poisonous CO into the atmosphere is a serious problem that must be solved at the level of industrial production. One of the effective directions in the field of purification of industrial gas emissions from toxic carbon monoxide is the application of catalytic technologies due to the use of compositions based on transition metals, especially ferrite materials. Recently, systems for neutralizing toxic gases, including glass fiber catalysts, have become widely popular. The study of the CO oxidation process was carried out on a flow-type installation with a stationary weight of the catalyst. Catalytic purification of the gas mixture from CO was studied in the range of 50-450 °C. The concentration of carbon monoxide in the initial gas mixture at the entrance to the reactor was varied in the range of 1-2 vol. %. If necessary, helium was used as an inert gas. Ceramic fiber was used as a fiberglass support for catalytic systems for the oxidation of gaseous emissions containing CO. Ferrite catalysts were applied to ceramic fiber by the method of impregnation from sulfate solutions of iron, copper, and potassium bichromate. From the temperature dependences of the conversion of carbon monoxide with a concentration of 1-2% on ferrite catalysts on a ceramic fiber carrier, it can be seen that 100% conversion of carbon monoxide is not achieved even at a temperature of 450 ºС. In the case of using a mixture of magnetite and copper ferrite, the degree of conversion of CO was 97% at temperatures above 300 ºС and stably ensured the neutralization of CO until the conversion degree of 98% was reached at a temperature of 450 ºС. At a temperature of 450 ºС, the highest degree of conversion of 99% was ensured by using chromium ferrite, but the specified chromium-ferrite catalyst at a temperature of 400 ºС provided a slightly lower oxidation efficiency, that is, the specified catalyst has less advantages for use in fluctuating gas temperatures in industrial conditions. When magnetite and copper ferrite were used separately, the degree of CO conversion was 40% and 75%, respectively. Therefore, the conducted studies showed that the use of ceramic fiber modified with ferrites can be effectively used for the purification of flue gases of electrode graphitization furnaces, in particular, the neutralization of toxic carbon monoxide. Obtaining ceramic fiber modified with ferrite material does not require significant capital investments, as it is based on the use of liquid waste from etching, copper plating, and chrome plating of galvanic production. Laying ceramic fiber on top of the thermal insulation of the graphitization furnaces of electrode production will also reduce the inflow of oxygen into the porous space and reduce the formation of carbon monoxide, which will contribute to the improvement of the ecological situation at the electrode production. The obtained results on the use of ceramic fiber modified with ferrite material as a catalyst for the neutralization of carbon monoxide are a highly effective and affordable measure to reduce the man-made burden of electrode production on the environment.

Nutritional profile and risk assessment of inorganic elements in enteral and parenteral nutrition formulas

The contents of essential (Ca, Fe, K, Na, P, and Zn) and potentially toxic inorganic elements (As, Al, Cd, Cr, Cu, Mn, and Pb) in enteral and parenteral nutrition formulas were evaluated by inductively coupled plasma optical emission spectrometry (ICP OES) and graphite furnace atomic absorption spectrometry (GFAAS). A total of 30 enteral formulas, 23 parenteral solution components, and 3 parenteral solutions were analyzed. The elements Ca and K presented the higher contents (72–2918 mg L−1 and 235–2760 mg L−1) while the lowest concentration levels were found for As and Cd (<0.68 µg L−1 and <0.01–0.62 µg L−1) in the studied samples. The validated analytical methods presented an accuracy of 75–116% and RSD values lower than 9.8%. Calcium gluconate and magnesium sulfate, which are used as raw materials in parenteral solution, are potential sources of Al and Mn contamination. A Hazard Quotient (HQ) >1 was obtained for Al (27 ± 1 µg L−1) in one of the parenteral samples, whereas the established limit is 25 µg L−1. Enteral samples were considered safe for consumption regarding the Al, As, and Cd levels. One healing-specific and pediatric formula contained Pb at levels above 0.25 µg kg-day−1, too high for safe consumption. The enteral formulas (pediatric, diabetes-specific, renal-specific, healing-specific, and standard formula with addition of fiber) presented risks in relation to the consumption of Cr and Mn (>250 µg day−1 and >11 mg day−1). The results indicate the need for strict monitoring, considering that these formulations are often the single patient’s food source.

Toxic metal levels in raw camel milk sold in the northern Algerian Sahara

ABSTRACT The consumption of camel milk is gaining popularity in Algeria. This study aimed to determine the concentrations of Lead (Pb), Cadmium (Cd), Nickel (Ni) and Mercury (Hg) in camel milk sold in Southeast Algeria and assess the potential health risks associated with its consumption. 120 samples of camel milk were collected from 10 farms located near the roads in the south of Algeria. Metals were measured using an atomic absorption spectrophotometer with a graphite furnace and Target Hazard Quotients (THQs) were calculated. The mean concentrations were 0.026 ± 0.013 mg/kg, 0.001 ± 0.0002 mg/kg, 0.017 ± 0.002 mg/kg and 0.0005 ± 0.0002 mg/kg for Pb, Cd, Ni and Hg. The THQ was higher for children, suggesting health risks associated with consumption of camel milk for this age group (p < .001). The primary contribution of this study is the establishment of a database on toxic metal levels in camel milk, which can be valuable to manage possible risk associated with metals in milk.

Design and Numerical Study of Induction-Heating Graphitization Furnace Based on Graphene Coils

Induction-heating graphitization furnaces are widely used to produce high-purity graphite products due to their high heating rate, high-limit temperatures, safety, cleanliness, and precise control. However, the existing induction-heating systems based on copper coils have limited energy efficiency. This paper proposes a new induction-heating graphitization furnace based on graphene coils. Due to the excellent high-temperature resistance of the macroscopic graphene material, the coil can be placed closer to the graphite heater, which improves the electromagnetic efficiency; the coil itself does not need to pass cooling water, which reduces the heat loss of the furnace and ultimately results in a higher energy efficiency of the induction furnace. In this paper, a numerical model of the induction-heating process is established and verified, the temperature-field and electromagnetic-field distributions of the heating process are analyzed by using the model, and the energy balance calculations are performed for the original furnace and the new furnace. Through a comparison, it was found that the new furnace possesses an electromagnetic efficiency of 84.87% and a thermal efficiency of 20.82%, and it can reduce the energy consumption by 33.34%, compared with the original furnace. In addition, the influence of the coil parameters on the performance of the induction furnace is discussed. By changing the coil conductivity, the induction furnace can achieve an energy efficiency of 17.76%–18.11%. This study provides new ideas for the application of macroscopic graphene materials in high-temperature induction heating.

Accumulation and toxicity of biologically produced gold nanoparticles in different types of specialized mammalian cells.

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 15nm in size with a zeta potential of -35.8mV. 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.

Analysis of polyphenols, anthocyanins and toxic elements in Açaí Juice (Euterpe oleracea Mart.): Quantification and in vivo assessment of the antioxidant capacity of clarified Açaí juice

This study aims to measure the concentration of total polyphenols, anthocyanins and inorganic contaminants (Al, Pb and Ni) in samples of açaí juice collected in the municipalities of Pará and evaluate the in vivo antioxidant capacity of purified açaí juice. Total polyphenols and anthocyanins were determined by UV/Vis spectrophotometry, while inorganic contaminants were measured using Graphite Furnace Atomization Atomic Absorption Spectrometry (GF-AAS) and Flame Atomic Absorption Spectrometry (F-AAS) after microwave-assisted digestion. The in vivo study lasted five days and involved 16 rats divided into four groups. The antioxidant capacity was evaluated through the formation of peroxyl free radicals (ACAP) in rat liver tissue. The average concentrations (mg GAE/DE) of total phenolic compounds averaged 27.34, with individual values ranging from 13.28 to 56.58. The average concentration (mg ANTO/g) of anthocyanins was 7.6, with individual concentrations ranging from 5.52 to 9.75. Contaminant concentrations (mg/kg) ranged from 1.82 to 11.74 for Al, 0.04 to 0.53 for Pb and 0.18 to 0.78 for Ni. The levels of Pb found in the samples may represent a concern to health. Al and Pb induced oxidative stress in the liver tissue, but Euterpe oleracea clarified juice (EOCJ) led to significant antioxidant protection. Animals treated with the highest dose of EOCJ (2.07 g/kg body weight) experienced an approximately five-fold reduction in ACAP compared to the group exposed to the metals (Al and Pb). The findings suggest the need to monitor inorganic contaminants in açaí products as well as the potential benefits of antioxidant compounds against the liver toxicity of Al and Pb.

Effects of Low-Level Inorganic Selenium on Selenium Bioaccumulation in Escherichia coli: A Bioanalytical Study Using Graphite Furnace Atomic Absorption Spectrometry (GFAAS)

This study aimed to assess the bioaccumulation of selenite – Se(IV) – and selenate – Se(VI) – in Escherichia coli ATCC 11775 biomass. Escherichia coli cultures were exposed to low selenium concentrations (0.3–30.0 µM), and subsequent effects on growth and viability were evaluated. Selenium content in biomass was quantified using graphite furnace atomic absorption spectroscopy (GFAAS) and inductively coupled plasma mass spectrometry (ICP-MS), with Se recovery assessed through mass balance analysis. The average percentage of bioaccumulated Se exhibited variability depending on the Se species at different concentrations. At a concentration of 30.0 μM, elemental selenium formation emerged within the Se(IV) assay, leading to a significantly higher mean percentage of bioaccumulated selenium for Se(IV) (41.1%) compared to Se(VI) (15.8%). While the mean percentage of bioaccumulated selenium showed no significant variance across the Se(VI) concentrations, a significant difference was observed across the Se(IV) concentrations (ranging from 6.1% to 41.1%). Considering the percentage of Se recovered in the solid and liquid phases, the mass balance ranged from 82.1% to 94.5%. These findings underscore the ability of Escherichia coli ATCC 11775 to accumulate notable quantities of selenium, with the amount of bioaccumulated Se influenced by Se(IV) concentration but not by Se(VI). Furthermore, bacterial viability remained unaffected by selenium species and concentrations. This study contributes valuable insights into the bioaccumulation dynamics of Se(IV) and Se(VI) in non-genetically modified Escherichia coli, shedding light on factors governing selenium accumulation in bacterial biomass, particularly regarding natural biological representation, standardization, comparability, and applicability to environmental studies.

Recent overview of microextraction of metal ions and pharmaceuticals by solidified floating organic drop microextraction techniques

AbstractThis 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.

Silver carboxylate-TiO2/polydimethyl siloxane is a safe and effective antimicrobial with significant wound care potential.

With the rise in antibiotic resistance, new methodologies are needed to combat musculoskeletal infections. Silver is an antimicrobial that can be synthesized in different forms, but its pharmacokinetics are difficult to control. This study details the antibacterial efficacy and cellular cytotoxicity of a formulation consisting of silver carboxylate (AgCar) released through a titanium dioxide/polydimethylsiloxane matrix with a predictable release profile on Pseudomonas aeruginosa, Acinetobacterium baumannii, and human-derived primary osteoblasts. Through an Institutional Animal Care and Use Committee and IRB-approved protocol, AgCar was applied to live Yucatan porcine skin and histologically analyzed for skin penetration. Graphite Furnace Atomic Absorption Spectroscopy (GFAAS) was used to measure elution of AgCar. Dose-response curves were generated through optical density to assess potency. Finally, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to quantify the cellular cytotoxicity of the novel formulation. The results were subject to statistical analysis using analysis of variance and post hoc Tukey tests. The silver carboxylate coating demonstrated deep penetration into the epithelium at the level of the deep pilosebaceous glands in animal models. GFAAS testing demonstrated the extended elution profile of silver carboxylate over 96 hours, while 100% silver with no titanium dioxide-polydimethylsiloxane matrix fully eluted within 48 hours. 10x silver carboxylate demonstrated superior antimicrobial activity to antibiotics and other silver formulations and showed minimal cytotoxicity compared with other silver formulations. Current antimicrobial therapies in wound care and surgical antisepsis, such as chlorhexidine gluconate, have pitfalls including poor skin penetration and short duration of efficacy. The broad antimicrobial activity, extended elution, and deep skin penetration of this AgCar formulation show great promise for surgical site infection and wound care treatment. Novel technology to fight the growing threat of microbial resistance should be at the forefront of orthopaedic surgical site infection prevention and treatment.