Electrothermal Atomic Absorption Spectrometry Research Articles

Effects of age and sex on the content of heavy metals in the hair, liver and the longissimus lumborum muscle of roe deer Capreolus capreolus L.

The aim of the study was to investigate the effects of age and sex on the content of heavy metals (Pb, Cd, Zn and Cu) in the hair, liver and the longissimus lumborum muscle of roe deer (Capreolus capreolus L.). In addition, correlations between heavy metals in individual tested matrices were studied as well as an attempt was made to explain the reasons for their accumulation in specific research matrices. The levels of Zn and Cu were measured using atomic absorption spectroscopy (F-AAS). The levels of Pb and Cd were analysed by means of electrothermal atomic absorption spectroscopy (ET-AAS). In the own research, sex-related statistically significant differences in concentrations of analysed elements were confirmed. Higher levels of the elements were observed in samples collected from does (except for Cd in the liver samples of 6–7-month-old male fawns) but only in some cases, these values were statistically significantly higher. In some cases, age-related differences in the content of individual metals were also confirmed. Age-dependent increased Pb levels in the muscle and liver were reported in 6–7-month-old, <3–4-year-old, <5–6-year-old males. Similar relationships were confirmed for Zn in the bucks’ muscles. In the group of does, the increase in heavy metal concentrations with aging was observed for Zn in the muscle and for Pb in the liver. In the other cases, the trend of age-related level changes regarding heavy metals was not clearly demonstrated. Significant positive correlations between Cu and Cd were found for all samples, and significant negative correlations of Cu with Pb were found for the hair and liver. There was a negative correlation of Zn with Cu in all matrices. The study also revealed a negative correlation between Zn and Pb in muscle and a strong significant negative correlation between Zn and Cd in hair and in the liver.

VALIDATION OF LEAD (Pb) ANALYSIS METHOD IN FISH MEAL MATRIX BY ELECTROTHERMAL ATOMIC ABSORPTION SPECTROPHOTOMETRY

ABSTRACT&#x0D; Validation of analytical methods is the process of proving that the methods used are scientifically good and suitable for certain purposes. The aim of this study was to validate the analytical method of lead in fish meal matrix by electrothermal atomic absorption spectroscopy (ETAAS) using a phosphate modifier. The research begins with optimization of the analytical conditions that include pyrolysis (ashing) and atomizing temperature, and continues with the validation process by evaluating the analytical performance parameters using a certified reference material (CRM). Method validation was carried out by determining the level of accuracy and precision as well as lead content in a CRM Cod Muscle-422 from BCR. Each experiment was conducted at a wavelength of 283.3 nm, a lamp current of 9.0 amperes, a slit width of 1.3 nm and an argon carrier gas. The optimal pyrolysis and atomizing temperature of lead obtained by adding phosphate modifier was 650 oC and 2000 oC, respectively. The results obtained in this study indicate that the ETAAS lead analysis method using a phosphate modifier is feasible as a test method with an RSD of 3.79%, precision of 0.0043, relative error of 4.0%, accuracy of 104% and recovery of 98% ± 3%. The results of the validation method obtained that the 95% confidence interval for Pb content was 0.088 ± 0.023 µg/g, still within the range of Pb levels in the certificate, namely 0.085 ± 0.015 µg/g of Pb.&#x0D; Keywords: Validation, CRM, Cod Muscle, ETAAS, Lead

Synthesis of polystyrene-polyricinoleic acid copolymer containing silver nano particles for dispersive solid phase microextraction of molybdenum in water and food samples

Polystyrene-polyricinoleic acid copolymer containing silver nano particles (AgPSrici) was synthesized and used in separation of molybdenum from different aqueous and foodstuff samples during a dispersive-µ-solid phase extraction approach. The synthesized nano particles were verified using Fourier transform infraredspectroscopy. An electrothermal atomic absorption spectrometry has been used for measurement of the studied ions. AgPSrici amount pH, sample volume, elution solvent kind, and the time of extraction were the effective parameters that were optimized by one-variable-at-one-time method. Analytical data of the method was calculated and limit of detection, relative standard deviation, limit of quantification were 0.022 µg L−1, 2.9%, 150, and 0.066 µg L−1, respectively. The synthesized adsorption capacity was obtained 170 mg g−1.Accuracy of the method was studied by performing the method on certified reference materials and the presence of different interfering ions was studied. Molybdenum content of different water and foodstuffs was determined by the introduced method.

A modular single-cell pipette microfluidic chip coupling to ETAAS and ICP-MS for single cell analysis

Accurate single-cell capture is a crucial step for single cell biological and chemical analysis. Conventional single-cell capturing often confront operational complexity, limited efficiency, cell damage, large scale but low accuracy, incompetence in the acquirement of nano-upgraded single-cell liquid. Flow cytometry has been widely used in large-scale single-cell detection, while precise single-cell isolation relies on both a precision operating platform and a microscope, which is not only extremely inefficient, but also not conducive to couple with modern analytical instruments. Herein, we develop a modular single-cell pipette (mSCP) microfluidic chip with high efficiency and strong applicability for accurate direct capture of single viable cell from cell suspensions into nanoliter droplets (30−1000 nL). The mSCP is used as a sampling platform for the detection of CdTe quantum dots in single cells with electrothermal atomic absorption spectrometry (ETAAS) for the first time. It also ensures precise single-cell sampling and detection by inductively coupled plasma mass spectrometry (ICP-MS).

Modern Methodological Approaches to Sample Preparation for the Determination of Trace Elements in Food Products and Plant Raw Materials

Introduction. Various copper compounds are most widely used as plant protection agents in agriculture. From a hygienic point of view, information on excessive accumulation of copper in plants related to the use of a specific formulation of copper-containing pesticides is of interest. Our objective was to assess feasibility of increasing statistical significance of results of determining low residue levels of a copper-containing pesticide in apple samples by flame atomic absorption spectrometry using a high-resolution spectrometer in combination with developed approaches to sample preparation of plant-based foods, including homogenization with dry ice and microwave mineralization. Materials and methods: We analyzed 30 samples of apples collected in three different agro-climatic zones by flame atomic absorption spectrometry and electrothermal atomization atomic absorption spectrometry. Both methods were validated on 10 samples with added copper at levels 1-5 of the lower limit of quantitation. A statistical calculation was performed based on a simple Student’s test to assess the significance of differences between the results of measurements by flame and electrothermal techniques. Homogeneity of variances was estimated using the Fisher test to clarify the possibility of comparing two data sets. Results: The use of a technique of cryo-grinding and microwave decomposition in a microwave reactor in combination with a high-resolution continuum source atomic absorption spectrometry demonstrated a decrease in scattering and the limit of detection and better repeatability in the analysis of parallel samples. Results of statistical calculations confirmed the homogeneity of variances in data samples obtained for electrothermal and flame techniques, and the further Student’s t-test showed insignificant differences between the results of measurements obtained by FAAS and ET-AAS. Conclusion: Our findings prove that modern methods of sample preparation in combination with highly sensitive equipment allow a significant reduction in the limit of detection and scattering of test results.

Optimization of straightforward methods for the monitoring of organic and inorganic contaminants in strawberries

Straightforward methods for the monitoring of chlorothalonil, cyprodinil, fludioxonil, metalaxyl-m, mancozeb and ethylenethiourea in strawberries, based on modified QuEChERS protocols followed by HPLC-DAD, were validated according to DG-SANTE Guidelines. Compounds showed satisfactory recoveries in the range 85.4–100.3% at spiking levels of 0.01, 0.02 and 0.05 mg kg−1, with RSDs below 15 %. LOQs were in the range 0.01 – 0.02 mg kg−1, being below the corresponding maximum residue levels (MRLs). Also, a simple method for the determination of Cd and Pb, based on a microwave-assisted digestion followed by electrothermal atomic absorption spectrometry (ETAAS), was validated according to Eurachem Guide. Trueness and precision were evaluated by analysis of a certified reference material (CRM). Results were statistically equivalent to the certified values at the 95 % significance level, while RSDs were below 5%. Methods were finally applied to the analysis of commercial samples. Residues of mancozeb and ethylenethiourea were detected in some of the samples but below the LOQs. Inorganic contaminants were in the range 0.0031 – 0.0088 mg kg−1 (Cd) and 0.0057 – 0.0212 mg kg−1 (Pb) (fresh weight), being below the corresponding maximum limits established by national regulation. The proposed methods can be easily implemented as routine analysis for food safety monitoring.

Environmental exposure to cadmium but not lead is associated with decreased semen quality parameters: quality regionalism of sperm properties.

Environmental factors may negatively contribute to a progressive worsening of semen quality, and differences in semen quality may result from different environmental exposures (regional differences) or lifestyle differences. Heavy metals are factors with a confirmed negative influence on male fertility. Among them, lead and cadmium are commonly found in human surroundings. Thus, we analyzed semen parameters (according to the World Health Organization 2010 recommendations) and semen lead and cadmium concentrations in 188 men from two different regions in Poland, a typical agricultural area and an industrial area, in couples that had been diagnosed with infertility. The assays were performed using flameless electrothermal atomic absorption spectrometry. In the statistical analysis, regional comparisons and then taxonomic comparisons based on three parameters (age, semen concentration, and sperm morphology) were applied. We showed that more cadmium than lead accumulated in semen, a higher cadmium concentration was observed in semen obtained from men from the agricultural region, and better semen quality and lower cadmium concentrations were found in the semen of men from the industrial, more polluted region. We thus showed an existing regionalism in the sperm quality properties. However, semen parameters such as morphology and progressive and nonprogressive motility followed the same trends, regardless of the patient's age, region, or class. We could conclude that the environment has a minor impact on sperm morphology and progressive and nonprogressive motility and that other existing factors could have an indirect influence on semen quality.

Ionic liquid functionlized on multiwall carbon nanotubes for nickel and lead determination in human serum and urine samples by micro solid-phase extraction

In this study, a novel synthesis adsorbent, 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate functionlized on multiwall carbon nanotubes ([Apmim][PF6]-MWCNTs, IL@MWCNTS) was used for nickel/lead (Ni/Pb) extraction and determination by dispersive ionic liquid micro solid-phase extraction (DIL-μ-SPE) coupled to electrothermal atomic absorption spectrometry (ET-AAS). After dilution of 20 mg of IL@MWCNTS in 200 μL of acetone, the mixture was injected to 10 mL of human serum/urine samples at pH of 8.0. After sonication for 5 min, the Ni(II) / Pb(II) were extracted by ionic liquid phase and then centrifuged for 2.5 min. The upper liquid phase set aside and Ni(II) / Pb(II) loaded in adsorbent were back-extracted by acidic solution at pH=2-3. Finally, the concentration of total nickel and lead was determined by ET-AAS. By optimizing, the limit of detection, linear range, and enrichment factor for nickel and lead were obtained (0.05 μg L−1; 0.1 μg L−1), (0.2-5.8 μg L−1; 0.4-30 μg L−1) and 24.7; 5.1, respectively (RSD less than 5%). Also, the capacity absorption of IL@MWCNTS for nickel and lead ions were achieved 149.3 mg g-1 and 162.5 mg g-1, respectively. The DIL-μ-SPE procedure was validated for nickel and lead extraction by spiking of real samples and ICP-MS analyzer.

The Toxicological Risk Assessment of Dermal Exposure of Patients Exposed to Nickel and Chromium due to Application of Ointments with Marjoram Herb Extract (Majoranae Herbae Extractum) Available in Polish Pharmacies

For elemental impurities that have been studied for transcutaneous absorption, the available data are rarely suitable for proper toxicological risk assessment — there are multiple factors that can influence this dermal absorption. Hence, in our studies, we applied generic and conservative approach — cutaneous permitted daily exposure (CPDE) described in International Conference on Harmonisation’s Q3D Guideline on Elemental Impurities (ICH Q3D). The aim of this article is toxicological risk assessment (TRA) of dermal exposure of patients exposed to nickel and chromium due to application of ointments with Marjoram herb extract (Majoranae herbae extractum) available in Polish pharmacies (n = 5, because only five manufacturers produce this kind of pharmaceutical products in Poland). To make the appropriate TRA approach, we considered (1) raw results (metal per kg of ointment), (2) one-time administration of applied ointments, and (3) daily exposure versus CPDE. Due to the fact the concentrations of Ni generally present in cutaneous products as impurities are not considered sufficient to induce sensitization, the cutaneous and transcutaneous concentration limits (CTCLs) approach was applied for this element assessment. The toxicological analysis was carried out using microwave-assisted wet digestion with concentrated nitric acid and electrothermal atomization atomic absorption spectrometry. Our results show that the ointments with Marjoram herb extract from pharmacies in Poland represent a potential health hazard to patients; however, there may be a requirement for the monitoring of impurities of nickel in future. To the best of our knowledge, this paper is the first study about nickel and chromium content in ointments with Marjoram herb extract (Majoranae herbae extractum).

Evaluation and determination of occupational and environmental exposure of lead in workplace air and human workers based dispersive ionic liquid solid phase micro extraction in battery manufacturing factories from Iran

The exposure of lead in workplace air and human workers of battery manufacturing factory was evaluated determined by nanotechnology since 2019-2020. Human whole blood (HWB) for subject and healthy peoples (25-55, Men, 40 N) and workplace air (40N) was prepared based on NIOSH sampling. 10 mL of HWB samples added to 20 mg of mixture ionic liquid/ ligand ([HMIM][PF6]/APDC) modified on graphene oxide nanostructures(GONs) at pH=6. After sonication, the lead ions separated/extracted by dispersive ionic liquid solid phase micro extraction (DIL-SPME) and determined by flame atomic absorption spectrometry (F-AAS). All air samples in workplace were analyzed based on NIOSH process. The results showed us the negative correlation between Pb concentration in human blood subject and healthy peoples (r=0.24). The range concentrations of lead in human subject, healthy peoples and workplace air were obtained 193.4-543.7 µg L-1, 85.6-175.9 µgL-1 and 44.7-81.5 µgm-3, respectively. The LOD, linear rang, enrichment factor(EF) and RSD% were achieved 1.25 µg L-1, 5.0- 310 µg L-1, 19.6 and less than 5% by procedure. The method was validated by standard reference material (SRM), the electrothermal atomic absorption spectrometry (ET-AAS) and ICP-MS analyzer for human samples.

A New Nanocomposite Packaging Based on LASiS-Generated AgNPs for the Preservation of Apple Juice.

Designing bioactive materials, with controlled metal ion release, exerting a significant biological action and associated to low toxicity for humans, is nowadays one of the most important challenges for our community. The most looked-for nanoantimicrobials are capable of releasing metal species with defined kinetic profiles, either by slowing down or inhibiting bacterial growth and pathogenic microorganism diffusion. In this study, laser ablation synthesis in solution (LASiS) has been used to produce bioactive Ag-based nanocolloids, in isopropyl alcohol, which can be used as water-insoluble nano-reservoirs in composite materials like poly(3-hydroxybutyrate-co-3-hydroxyvalerate). Infrared spectroscopy was used to evaluate the chemical state of pristine polymer and final composite material, thus providing useful information about synthesis processes, as well as storage and processing conditions. Transmission electron microscopy was exploited to study the morphology of nano-colloids, along with UV-Vis for bulk chemical characterization, highlighting the presence of spheroidal particles with average diameter around 12 nm. Electro-thermal atomic absorption spectroscopy was used to investigate metal ion release from Ag-modified products, showing a maximum release around 60 ppb, which ensures an efficient antimicrobial activity, being much lower than what recommended by health institutions. Analytical spectroscopy results were matched with bioactivity tests carried out on target microorganisms of food spoilage.

Cloud Point Extraction Used for Separation and Preconcentration of Trace Elements in Food Samples: A Review of Recent Applications

Food safety analysis involves many subfields. One of them is inorganic analysis aimed to the quantification of various trace elements. The main attention in this field is paid to toxic, potentially toxic, and essential trace elements. However in many cases, direct quantification of trace elements in a complex food matrix is almost impossible. To resolve this problem, a combination of a suitable separation procedure with a reliable quantification method is required to deliver accurate results. One of the separation techniques that is currently receiving considerable attention is cloud point extraction (CPE). The use of optimized CPE procedures with commonly available spectrometric methods (e.g., UV-Vis spectrophotometry, flame atomic absorption spectrometry, electrothermal atomic absorption spectrometry, hydride generation atomic absorption spectrometry, cold vapor atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry) provides the powerful tool for reliable quantification of many trace elements (e.g., Al, As, Cd, Cu, Hg, Pb, Mn, Ni, Sb, Se, Sn, Zn, and many others) in various types of food matrices (e.g., fresh vegetables, ground grain samples, canned food samples, various powdered food samples, and many others), as documented by studies included in this review.

Mercury Speciation in Natural and Mining-Related Systems

Mercury speciation and the composition of mercury phases in natural and mining-related environments is studied by the thermal release analysis combined with electrothermal atomic absorption spectroscopy (TA-ET-AAS), as well as scanning electron microscopy with energy-dispersive X-ray microanalysis (SEM-EDS). The analyses are applied to laboratory-made samples bearing mercury selenide and to field samples from sites known for relatively high natural or industrially induced Hg background. They are, namely, material from the dispersion train of the Ursk sulfide tailings (Ursk Village, Kemerovo region) and debris precipitated from snow sampled in the Kurai mercury zone (Aktash Village, Gorny Altai). The TA-ET-AAS method works well in discrimination and identification of Hg sulfide and Hg selenide provided that the samples contain sufficient amounts of both compounds, but the sum HgS + HgSe can be determined at any contents of the two compounds. The presence of both mercury sulfide and mercury selenide in the samples has been confirmed by SEM-EDS microanalysis. The temperature ranges for the mercury species (Hg2+; HgS+HgSe mixture; mercury bound with organic matter (Hg-OM), including CH3Hg+) are identical in the laboratory and field samples. Therefore, the suggested approach can ensure fast and reliable detection of Hg phases in rocks exposed to supergene alteration

Determining the authenticity of turmeric

The paper examines the problem of the composition instability in the ready ground spice, turmeric. Analysis of the prevalent methods for turmeric adulteration and substances used for these purposes is given. The visual assessment of color tints of the turmeric root, spices containing it and chemical dyes based on chromium salts is presented. The studies on determination of the lead and chromium content were carried out to study the content of these metals and test the hypothesis of using lead chromate as a dye in adulteration of turmeric. Using the method of electrothermal atomic absorption spectroscopy, it was found that the lead content in the analyzed turmeric samples varied from 1.72 ± 0.58 to 5.03 ± 1.80 mg/kg, while the chromium content was in a range of 5.56 ± 0.85 to 16.15 ± 2.32 mg/kg. As a result of species specific PCR, wheat DNA was revealed in all purchased samples of ground turmeric. The levels of the main raw material replacement were established, which were 0.14% to 14.95% with the correlation coefficient close to 100%; efficiency of the reaction was 1.95, which was 97.5% when expressed as percentage. These levels of an undeclared allergen in the product composition can cause a serious allergic reaction. The authors tested the hypothesis of introduction of sodium and potassium salts for correction of the color spectrum in the ready spice and its correspondence to the natural color within the color spectrum of turmeric. As a result of the complex study of the spice composition, quite high values of chromium were found, presumably not only from the lead chromate compound but also from chromic acid salts, as the high level of potassium that significantly exceeded the native content of this element was found.

The Levels of Mineral Elements and Toxic Metals in the Longissimus lumborum Muscle, Hair and Selected Organs of Red Deer (Cervus elaphus L.) in Poland.

Simple SummaryThe relationships between nutritive elements (Fe, Mn, Zn, Cu, Na, K, Ca and Mg) and toxic metals (Pb and Cd) can inform the assessment of health status of red deer, which are exposed to pollution in their natural environment. These elements in the longissimus lumborum muscle, hair and selected organs of red deer (Cervus elaphus L.) were analysed. The study revealed many significant correlations between the levels of elements and their high variability in individual tissues and organs. The accumulation of a specific metal in a tissue or organ can reduce its concentration in another matrix or promote increased content in another tissue or organ. The aim of the study was to analyse correlations and variability between the levels of mineral elements (Fe, Mn, Zn, Cu, Na, K, Ca and Mg) and toxic metals (Pb and Cd) in the longissimus lumborum muscle, hair and selected organs of red deer (Cervus elaphus L.). The levels of mineral elements were measured using atomic absorption spectroscopy (F-AAS). The levels of Pb and Cd were analysed by means of electrothermal atomic absorption spectroscopy (ET-AAS). Of all analysed microelements, the highest concentration (in g·kg−1 of dry weight) was found for Fe in the liver. Considering all macroelements, the highest level was found for K in the longissimus lumborum muscle. Particularly remarkable was the high level of Pb in the muscle and hair of red deer. The level of Cd in the hair was four to five times lower than in other samples. The study revealed many significant correlations between the levels of certain elements in individual tissues and organs. There were significant correlations between Cu-Fe (rxy = 0.650; p ≤ 0.01), Pb-Cu (rxy = −0.863; p ≤ 0.01) and Cd-Ca (rxy = −0.743; p ≤ 0.01) in testicles. For kidneys, a significant negative correlation was found for K and Na (rxy = −0.779; p ≤ 0.01) and for Ca and Cd (rxy = −0.695; p ≤ 0.01), and a positive correlation between Cu and Mn (rxy = 0.693; p ≤ 0.01). In the liver, significant negative correlations were found between Ca-K (rxy = −0.654; p ≤ 0.05), Cd-Fe (rxy = −0.651; p ≤ 0.05) and Pb-Cu (rxy = −0.627; p ≤ 0.05). In the muscle, only single significant correlations were found between Cd and Mn (rxy = 0.648; p ≤ 0.05). The highest number of significant correlations were recorded for the hair, among others between Na-K (rxy = 0.760) and Ca-Zn (rxy = 0.709) at p ≤ 0.01. The study revealed high variability in the levels of mineral elements and selected toxic metals in tissues, organs and hair of red deer. Additionally, this research confirmed that the accumulation of a specific metal in a tissue or organ can reduce its concentration in another matrix or promote its increased content in another tissue or organ.

Dispersive solid phase extraction of Ni2+ using graphene oxide-polyethylenimine nanocomposite as an efficient adsorbent in different real samples; Response surface methodology based on central composite design optimisation

ABSTRACT An efficient modified graphene oxide adsorbent was used for dispersive solid phase extraction of trace levels of Ni2+ followed by its determination using electrothermal atomic absorption spectrometry (ETAAS). Graphene oxide modified polyethylenimine nanocomposite (GO-PEI) was used as an adsorbent and characterised by the Fourier Transform-Infrared Spectrophotometry (FT-IR), Field Emission Scanning Electron Microscopy (FE-SEM), Energy Dispersive X-Ray Spectroscopy (EDX) and X-Ray Diffraction Analysis (XRD). In order to optimise the critical parameter affecting the extraction efficiency of Ni2+, the response surface methodology based on central composite design (RSM-CCD) was used. Under the optimum condition, the calibration curve was found to be linear in the range of 0.1–2.0 µg L−1 with a correlation coefficient of 0.9997. The inter-day relative standard deviation (RSD) was 3.5% based on seven replicate analysis of 1.0 µg L−1 Ni2+ and the limit of detection (LOD) was 0.018 µg L−1 (n = 8). The accuracy of the proposed method was checked by the analysis of certified reference material-trace metals in drinking water (CRM-TMDW) and then it was successfully applied for determination of trace levels of Ni2+ in different real samples.

The Toxicological Risk Assessment of Lead and Cadmium in Valeriana officinalis L., radix (Valerian root) as Herbal Medicinal Product for the Relief of Mild Nervous Tension and Sleep Disorders Available in Polish Pharmacies

Studies related to the toxicological risk assessment (TRA) of heavy metal impurities (HMIs) in pharmaceuticals are an important issue but there is a lack of refereed literature around the safety of Valeriana officinalis L., radix (Valerian root) as herbal medicinal product (HMP) for the relief of mild nervous tension and sleep disorders according to lead and cadmium impurities. The aim of the study was to estimate the TRA of lead and cadmium in Valeriana officinalis L., radix (Valerian root) as HMP (n = 5) available in Polish pharmacies. In the case of herbal pharmaceuticals, it is particularly important to control the level of HMIs accumulated during the plant’s growth. Perhaps, the exposure for a single dose is not relevant; however, justification of our studies is a fact that herbal therapies are usually long term. Therefore, even small HMI doses as present in particular plant may accumulate in patient body over a long period of time. Levels of lead and cadmium were measured by electrothermal atomization atomic absorption spectrometry. The levels of lead and cadmium as HMIs (independently of the producer and declared composition) are quite similar. Our results are satisfactory, confirming the safety of Valeriana officinalis L., radix (Valerian root) as herbal medicinal product for the relief of mild nervous tension and sleep disorders available in Polish pharmacies according to ICH guideline Q3D. To the best of our knowledge, this paper is the first study about lead and cadmium content as HMIs in HMP containing Valeriana officinalis L., radix (Valerian root).

Determination of the dissolved forms of silicon in natural drinking water using high-resolution continuum-source electrothermal atomic absorption spectrometry

A technique for the determination of dissolved forms of silicon in water using high-resolution continuum-source electrothermal atomic absorption spectrometry (HR-CS-ETAAS) is proposed. The quantitative determination of the dissolved forms of silicon was performed using an atomic absorption spectrometer ContrAA 700 with a graphite cross-heating cuvette. Natural water was selected to optimize the temperature-time program of the atomizer. To eliminate chemical interference during the silicon determination by HR-CS-ETAAS, the graphite cuvettes were modified with a permanent modifier to form a carbide coating. A solution of sodium tungstate was used as a permanent modifier. Thermal stabilization of silicon in a graphite furnace was achieved with a mixed palladium-magnesium modifier present in the nitrate form. The developed method was used for determination of the content of the dissolved forms of silicon in water. The developed technique was certified proceeding from the results of the research and the metrological examination by an organization accredited for this type of the activity and registered in Federal information Fund for ensuring the uniformity of measurements (FIF).

Preparation and application of Fe3O4@ SiO2@ poly (o-phenylenediamine) nanoparticles as a novel magnetic sorbent for the solid-phase extraction of tellurium in water samples and its determination by ET-AAS

A novel magnetic polymer (Fe3O4@ SiO2@ PoPD) is synthesized for the magnetic solid-phase extraction (MSPE) of tellurium from water samples and its determination by electrothermal atomic absorption spectroscopy (ET-AAS). The morphology, composition and magnetic properties of the synthesized nanoparticles are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometery (VSM). The factors affecting separation and preconcentration of tellurium including the amount of sorbent, composition of sorbent material, extraction time and temperature, desorption time and temperature, pH and ionic strength of the sample solution, desorption solvent type, concentration and volume are studied. Under optimized experimental condition, the linear range and the detection limit of the method are 0.08–1.9 ng mL−1 (R2 = 0.9879) and 0.05 ng mL−1, respectively. The percent recovery of tellurium from real samples spiked at 0.5 ng mL−1 is more than 98%. The intraday and interday relative standard deviations for a batch of the sorbent at above concentration level are 4.3 and 5.6%, respectively. The sorbent-to-sorbent RSD% is 8.9%. Finally, the developed method is successfully applied to the analysis of tellurium in some real samples.

Determination of total and extractable amount of aluminum, copper, zinc, and lead in surgical suture threads by electrothermal atomic absorption spectrometry

Polymer-based materials such as surgical suture threads are the most important raw materials used in the manufacturing of medical devices. Determination of metal contamination in industrial surgical threads such as absorbable polydioxanone (PDO) and polyglycolic acid (PGA), and nonabsorbable polypropylene (PP) is very important for human health. Concentrations of aluminum, copper, zinc, and lead released from these surgical suture samples into various solutions were determined. The effects of parameters such as solvent type, temperature, pH of solvent, and time for release of these metals from the samples were investigated to determine optimum conditions. The extractable and total amount of aluminum, copper, zinc, and lead in PDO, PGA, and PP samples were performed by using electrothermal atomic absorption spectrometry. The aluminum, copper, zinc, and lead in certified standard material solution (IQC-026 mixture) were determined for the accuracy of the method. Limits of detection and quantification values of analytes found were 2.8 and 9.3 µg L−1 for aluminum, 1.5 and 5.0 µg L−1 for copper, 1.5 and 5.0 µg L−1 for zinc, and 2.9 and 9.7 µg L−1 for lead, respectively.