Flame Atomic Absorption Spectrometry Method Research Articles

Simultaneous determination of inorganic ions in saline water from the Mekong Delta using ion chromatography

ABSTRACT The economy of Vietnam is significantly influenced by agriculture, forestry, and fisheries; thus, developing analytical methods to assess water quality is crucial. Salinization is an escalating concern in the Mekong Delta, particularly in Ben Tre province, where it adversely affects the livelihoods and local economy. In saline water, besides NaCl, which is the predominant component, other ions such as K+, Ca2+, Mg2+, and SO4 2− are vital for crop development. This study introduces an ion chromatography technique with conductivity detection capable of simultaneously analyzing six ions in saline water samples with high precision. The standard curves demonstrated excellent linearity with a correlation coefficient (R2 >0.995) and commendable repeatability (%RSD <5%) for concentration ranges of 1–10 mg L−1 for cations, 0–10 mg L−1 for SO4 2−, and 10–50 mg L−1 for Cl−. The outcomes will be compared with those of reference methods, including Flame Atomic Absorption Spectrometry, Mohr Titration, and Turbidimetric Methods, revealing no significant differences in ion concentration determinations across six saline water backgrounds in Ben Tre province.

ANÁLISE DE METAIS POTENCIALMENTE CONTAMINANTES NOS PEIXES DO RIO TAQUARI, BACIA DO RIO PARAGUAI, MUNICÍPIO DE COXIM-MS

In this study we analyzed the concentration of the metals Cd, Cu, Pb, Fe and Ni in the muscle tissue and digestive tract of 13 species of fish from the Taquari River, collected in the northern region of the state of Mato Grosso do Sul, in the Coxim micro-region, in order to quantify and compare the concentrations of these analytes present in these fish with the regulations for inorganic contaminants in Brazil (MERCOSUR) and abroad (FAO/WHO), thus making it possible to indicate whether they are within acceptable standards. The analyses were carried out using the Flame Atomic Absorption Spectrometry method and the results obtained indicate that Cd and Pb were not detected in all species. For Fe, Cu and Ni, no limits stipulated by legislation were found. Finally, the analysis showed that there are no factors of contamination by potentially contaminating metals through the consumption of fish by the population.

On-line determination of the trace amount of cobalt(II) in real samples by flame atomic absorption spectrometry method after pre-concentration by modified polyvinyl chloride

This work reports a simple and sensitive on-line solid-phase extraction system for the pre-concentration and determination of a trace amount of Co(II (ions by flame atomic absorption spectrometry (FAAS). This method is based on the on-line retention of cobalt ions with polyvinyl chloride modified by 3-(2-thiazolylazo)-2,6-diaminopyridine in a mini-column system. The retained Co(II) ions were eluted with 1.0 mol L−1 HCl, and direct aspiration to flame atomic absorption spectrometry (FAAS) for an accurate determination of it. The important experimental parameters such as the solution pH, length of column (adsorbent mass), sample flow rate, solvent eluent, type and concentration of the eluent, and co-existing ion effects were investigated in detail and optimized. Under the optimum conditions, the calibration graph was linear over the concentration range of 2–150 µg L−1 for pre-concentration of 10.0 mL of the sample solution. The interassay precession (n = 6) was in the range of 1.8–5.2% at the concentration levels of 10.0, 50.0, 100.0, and 140.0 µg L−1. The limit of detection and enhancement factor were 1.3 µg L−1 and 40, respectively. The method was applied for determination of trace levels of Co(II) ions in different real samples such as tap water, waste water, vegetable, fruit, and drug with satisfactory results.

Presence of heavy metals in over the counter teeth whitening products- An evaluative study.

Dentistry plays a crucial role in shaping the facial aesthetics of a person and thus boosts self-esteem. Tooth discolouration is one of the significant cosmetic problems and hence, many teeth whitening products are widely used for discolouration. However, these products may have heavy metals or chemicals that can affect the tooth and other organs. The aim is to estimate the amount of heavy metals present in teeth whitening products available for purchase over-the-counter in the pharmacies. A cross-sectional study of teeth whitening products available Over the Counter (OTC) in pharmacies in Chennai and adjoining districts of Tamil Nadu was conducted during the period from December 2019 to February 2020. The Flame Atomic Absorption Spectrometry (FAAS) method was used to measure the heavy metals such as inorganic lead, chromium, cobalt, arsenic, cadmium, nickel and mercury in the products. We collected 39 products and finalized nine for analysis. These products were available as tablet (n = 1), liquids (n = 2) and powders (n = 6). All products were mentioned as herbal or natural. Three products contained inorganic lead levels in parts per million (ppm) of 759 (product 2); 39.4 (product 3) and 28.1 (product 7), way above the permitted levels. None of the other heavy metals were detected from these products. After analysis with the FAAS method, inorganic lead over and above the permissible levels was observed. Dental professionals and community need to be aware of the availability of such products and its detrimental effects on oral and general health.

Development of a Sensitive Method for Cadmium Determination in Fish Tissue and Drinking Water Samples by FAAS Using SQT In Situ Atom Trapping.

A sensitive and robust trap method was developed for the determination of cadmium (Cd) by using a slotted quartz tube. Using this method at a sample suction rate of 7.4 mL/min for 4.0 min collection, a 1467-fold increase in sensitivity was obtained compared to the flame atomic absorption spectrometry method. Under the optimized conditions, a limit of detection of 0.075 ng mL-1 was obtained for the trap method. The interference effects of hydride-forming elements, transition metals, and some anions on the Cd signal were investigated. The developed method was evaluated by analyzing "Sewage Sludge-industrial origin (BCR no: 146R)", "NIST SRM 1640a Trace elements in natural water", and "DOLT: 5 Dogfish Liver". There was a good agreement between the certified and found values at the 95% confidence level. This method was applied successfully for the determination of Cd in drinking water and some fish tissue samples (liver, muscle, and gill) obtained from Muğla province.

A facile approach for grafting ion imprinted polymer onto magnetic multi-walled carbon nanotubes for selective removal and preconcentration of cadmium in food and wastewater samples prior to atomic spectrometric determination

A 3D Fe3O4@MWCNT-CdIIP was synthesized by the oxidizing surface of multi-walled carbon nanotubes with carboxylic acid end groups and its subsequent termination with an ion imprinted polymer. An artificial neural network manifests better predictability than the central composite design methodology for optimising the adsorption procedure. The adsorption capacity was 109 mg g−1 (2.5 times more than non-imprinted polymer) under optimized conditions (pH; 5.6, time; 15 min, concentration; 800 μg mL−1 temperature; 25 °C), which was in accord with Toth isotherm. Fractal-like pseudo-second-order kinetics was found reasonably fast, with 66 % adsorption in 5 min. Solid phase extraction coupled Flame atomic absorption spectrometry method provides selective recognition towards Cd(II), with limit of detection; 1.13 µg/L, limit of quantification; 3.21 µg/L after preconcentration (preconcentration factor; 50) and good robustness. The developed method was applied for Cd(II) determination in food (tea, coffee, bread, tobacco, radish, spinach), water and wastewater (>99 % removal as well). Cd(II) loaded IIP was further utilized to remove anionic dyes with >95 % removal.

The presence of hydroquinone, and mercury in skin toning creams, as well as lead in turmeric powder, pose potential health risks to Bangladeshi women

Skin toning creams and turmeric powders are widely used among Bangladeshi fashion and beauty concerned women and young girls in general. However, it has been reported that excessive use of skin toning cream and turmeric powder can cause various dermatological problems, including skin cancer. These creams and turmeric powder contain a wide variety of active ingredients, including Hydroquinone (HQ), Mercury (Hg), and Lead (Pb), that are toxic, and hazardous to health, especially after prolonged application. As a result, in the current study, we tried to assess HQ and Hg level in commonly used skin toning creams and Pb in turmeric powder in the context of Bangladeshi women collected from the local markets in Dhaka city. HQ, Hg, and Pb levels were analyzed for 40 different Bangladeshi skin toning cream products and 40 different turmeric powder samples. The HQ level was determined by the high-performance liquid chromatography (HPLC) method, the Hg level was determined by Cold Vapor Atomic Absorption Spectrophotometry (CV-AAS) using an automatic mercury analyzer, and Pb was measured by the flame atomic absorption spectrometry method. Among the 40 samples, 23 samples (57.5%) did not contain HQ, whereas 17 samples (42.5%) contained a high level of HQ compared to the standard limit. In the case of Hg analysis, we found that 28 (70%) out of 40 samples complied with the standard level of Hg, whereas 12 samples (30%) contained a higher level of Hg compared to the standard limit. Among the 40 samples of turmeric powder, 20 samples (50%) complied with the standard level of Pb, whereas 20 samples (50%) contained a high level of Pb compared to the standard limit. After three and six months of storage, we had similar results in all the samples for the three cases. After combining HQ and Hg data sets, we found that 14 (35%) out of the 40 samples had HQ and Hg levels within the standard limit, and 3 samples (7.5%) had higher quantities of both HQ and Hg levels and did not comply with the standard limit. 14 samples (35%) in the data set had higher HQ levels but complied only with the standard Hg level, whereas 9 samples (22.5%) had higher Hg levels and thus complied only with the standard HQ level. So, in 65% of the samples, we found the presence of excess level of either both HQ and Hg at the same time or any one of the measured chemical parameters. The use of these creams and turmeric powders, which did not comply with the standard limit, may pose a serious health risk to consumers. So, consumers should be aware of the risks associated with using these creams and turmeric powders, and policymakers should take appropriate measures to prevent the manufacturing and marketing of skin toning creams containing high levels of HQ and Hg and turmeric powder with high levels of Pb. Bioresearch Commu. 8(2): 1132-1142, 2022 (July)

Review of analytical methods for lead determination in paints and varnishes

Introduction. The draft Technical Regulation of the Eurasian Economic Union “On the Safety of Paint and Varnish Materials” establishes the lead content in paint and varnish materials for interior and exterior surfaces of residential and (or) public premises, furniture products, playgrounds, products for children and adolescents, attractions, products in contact with food, and used for water treatment equipment at a level not exceeding 0,009% of the total weight of non-volatile chemicals with a transition period of 60 months. Current GOST R 50279.10-92 (ISO 6503-84) (GOST R 50279.10-92 (ISO 6503-84). Paints and varnishes. Methods for determination of metal content. Determination of total lead content. Flame atomic absorption spectrometry method) and GOST R 50279.3-92 (ISO 3856/1-84) (GOST R 50279.3-92 (ISO 3856/1-84). Paints and varnishes. Methods for determination of metal content. Determination of “dissolved” lead content. Flame atomic absorption spectrometry and dithizone spectrophotometric method) with detection limits of lead at 0,01% (by weight) do not provide the required sensitivity, and therefore it becomes necessary to develop and approve in accordance with the established procedure an analytical method for lead determination in paint and varnish materials at the level of 0,0045% of the total weight of non-volatile chemicals (1/2 of the established standard). Materials and methods. Documents, guidelines and webinars of the Eurasian Economic Union, the World Health Organization, the United Nations Environment Program, the American Society for Testing and Materials (ASTM International), the International Organization for Standardization (ISO), the US Environmental Protection Agency (EPA), manufacturers of analytical equipment (26 sources in total) were used in the preparation of the review. Results and discussions. The review presents the most common methods for lead determination in paints and varnishes, indicating their characteristics, advantages and limitations: flame atomic absorption spectrometry; atomic absorption spectrometry with electrothermal atomization; atomic emission spectrometry with inductively coupled plasma; X-ray fluorescence spectrometry. Conclusion. A systematic analysis of the methods for lead determination in paints and varnishes existing in domestic and foreign practice, taking into account the lower detection limit, as well as the costs of consumables and equipment maintenance, allows to identify three methods that are of interest in terms of developing guidelines: atomic absorption spectrometry with electrothermal atomization; atomic emission spectrometry with inductively coupled plasma; high-resolution X-ray fluorescence spectrometry.

Elemental Profiles of Legumes and Seeds in View of Chemometric Approach

The study aimed to evaluate fourteen elements’ profiles of legumes and oilseeds, of various geographical origins, available on the Polish market. They were determined by flame atomic absorption spectrometry (F-AAS) and spectrophotometric method (phosphorus) in 90 analytical samples. In general, legumes were characterized with lower mean concentrations of Ca, Mg, Na, P, Zn, Cu, Fe, Mn, and Cr than oilseeds. However, the concentrations ranges within each group differed significantly (p &lt; 0.05). Calcium content varied between 6.2 and 243.5 mg/100 g in legumes and 38.4 and 2003 mg/100 g in oilseeds. In the case of Fe, its concentration was between 1.99 mg/100 g and 10.5 mg/100 g in legumes, and 2.05 mg and 12.15 mg/100 g in seeds. All the samples were characterized with Pb concentration below the LOQ (30 µg/100 g). In the case of Cd, its presence (&gt;LOQ, 9 µg/100 g) was confirmed in one sample of legumes (soybean) and five samples of seeds (poppy seeds, roasted linseeds, hulled wheat, linseed, and sunflower seeds). The detected Cd content in every sample, except for soybean and hulled wheat, exceeded the permissible European standards. According to Kruskal-Wallis test results, Mg, Na, K, P, Zn, Cu, Mn, Cr, and Cd content depended on the type of the analyzed product, while in the case of botanical provenance such relationship was recorded for most of the analyzed components, except for Fe, Cr, and Co. Factor and cluster analyses classified the analyzed samples in view of their botanical species and type based on their mineral composition.

Analytical Assessment of Bioelements in Various Types of Black Teas from Different Geographical Origins in View of Chemometric Approach

A comprehensive approach to the mineral composition of black teas of different origins was studied using the Flame Atomic Absorption Spectrometry (FAAS) method, supported by chemometric tools including Principal Component Analysis PCA) and Classification and Regression Trees (CART). Significant differences between the teas from seven countries (Japan, Nepal, Kenya, Iran, Sri Lanka, India, and China) were shown. K was the main element determined in all teas, with an average concentration of 11,649 mg/kg, followed by Ca, Mg and Mn. In general, regarding all investigated black teas, the element content was ranked in the following order: K > Ca > Mg > Mn > Fe > Na > Zn > Cu. The applied chemometric methods allowed us to recognize black tea clusters based on their mineral composition and place of cultivation, and allowed us to find correlations between particular elements in black teas. The performed analyses revealed interesting correlations between the concentration of various elements in black teas: K was negatively correlated with Na, Fe, Mn and Cu; K was positively correlated with the content of Ca and Mg. Significant positive correlations between Mn and Fe and Mn and Zn in the studied black tea samples were also revealed. It was shown that mineral composition may be a significant factor regarding the origin of the black tea, not only considering the country, but also the region or province.

Analysis and Evaluation of Nutritional Components in Akebia trifoliate Fruit

In order to analyze and evaluate the nutritional value of Akebia trifoliata fruit,Flame Atomic Absorption Spectrometry,Liquid Chromatography,Fluorescence Spectrophotometry and other experimental methods was used to detect and analyze the nutritional components in the peel,pulp and seed of Akebia trifoliata. Based on the detection and analysis,it could be seen that Akebia trifoliata fruit had high nutritional value. Among them:The peel of Akebia trifoliata contains mineral nutrients of Mn and K,the contents of Mn and K were 0.645 and 342 mg/100 g respectively. The total amino acid content in the peel of Akebia trifoliata was 0.313 mg/100 g,containing 15 kinds of amino acids,including 7 kinds of essential amino acids. The proportion of essential amino acids reached the ideal protein conditions proposed by WHO/FAO. The content of essential amino acids was less than that of pulp,and the nutritional value was lower than that of pulp. It contained a small amount of vitamin E,pectin,protein and fat. The seed of Akebia trifoliate contained many mineral nutrients,including K,P,Ca and Fe,with the contents of 586,180,191 and 2.85 mg/100 g,respectively. The seed of Akebia trifoliata was rich in many mineral nutrients,including Mn,Cu and Mg,with the contents of 4.63,1.3 and 157 mg/100 g,respectively. The fatty acid content was 2.662 g/100 g,and the proportion of unsaturated acid was 76%. The pulp of Akebia trifoliate contains Cu mineral nutrients and the content was 0.25 mg/100 g,was rich in Mn mineral nutrients and the content was 7.51 mg/100 g. The total amino acid content of Akebia trifoliata was 0.419 mg/100 g,containing 16 kinds of amino acids,including 8 kinds of essential amino acids. The proportion of essential amino acids reached the ideal protein conditions proposed by WHO/FAO,the content of essential amino acids was balanced and the nutritional value was high small amounts of vitamins,fats,proteins and flavonoids. This paper can provide theoretical support and technical guidance for the development and utilization of Akebia trifoliata,and promote the theoretical research process of Akebia trifoliata.

Aggregation of Nanochemical Microcrystals in Urine Promotes the Formation of Urinary Calculi

With the increasing incidence and recurrence rate of urinary calculi, urinary calculi have become a serious health risk, and the research on urinary calculi has become the focus of public attention. At present, the research results on the formation mechanism of urinary calculi are not ideal, and there is no unified conclusion. In order to further study the influencing factors of the formation of urinary calculi and provide new ideas for the prevention and clinical treatment of urinary calculi, the influence of agglomeration of nanochemical microcrystals in urine on urinary calculi was studied in this paper. In this study, fresh morning urine was collected from 10 urological stone patients and 10 healthy controls without urological stone in the urology department of a hospital. After processing the experimental specimens, we first use flame atomic absorption spectrometry and alcian blue colorimetric method to detect the content of Ca2+ and citrate in the urine and then use the nanoparticle size analyzer to detect the microcrystals in the urine. Diameter, distribution, degree of aggregation and potential, and finally HRTEM observation to observe the morphology, chemical composition, and element composition of the nanocrystals. The results showed that the content of Ca2+ and lemon hydrochloric acid in the urine of the experimental group was lower than that of the control group. The particle size of the nanocrystals increased with the increase in the pore size of the membrane. The average particle size of the experimental group increased gradually from 163 ± 31 nm to 3219 ± 863 nm, while the average particle size of the control group increased from 183 ± 65 nm to 997 ± 522 nm. The mean value of the potential decreased with the increase in the pore size of the filter membrane. The change amplitude of the experimental group was 6.57 mV, while the change amplitude of the control group was only 1.75 mV. In the composition of nanocrystals, element O accounts for the most, accounting for 42.54% of all elements. This indicates that the aggregation of nanocrystals in urine will lead to the rapid increase in the size of nanocrystals, which will eventually lead to the formation of stones.

Biofortificación de tomate (Solanum lycopersicum L.) con cianocobalamina y micronutrientes aminoquelados (Zn, Fe)

Introducción: El tomate constituye una fuente importante de nutrientes, catalogándose como un alimento óptimo para fortificar la población que presenta déficit de hierro, zinc y cianocobalamina.Material y métodos: Se aplicaron dos tratamientos, uno con minerales inorgánicos y el otro con minerales aminoquelado mediante un proceso de biofortificación foliar. Se cuantificó la concentración de los micronutrientes utilizando el método de Espectrometría por Absorción Atómica de llama directa (EAAF), se utilizó el método EPA 3052 para la evaluación de los minerales. Para el análisis de Cianocobalamina, se usó el método de Cromatografía Liquida (HPLC). Resultados: Se encontró diferencias altamente significativas (p&lt;0,0001) entre los tratamientos en la presencia de minerales, presentándose una mayor concentración de hierro en el tratamiento aminoquelado, 189,53±100,12 mg/kg. En el tratamiento inorgánico la mayor concentración fue de zinc, 89,82±21,67. Al evaluar el contenido de zinc, no hubo deferencias entre la biofortificación con el aminoquelado y el inorgánico (p&gt;0,05), con respecto a la cianocobalamina los datos bromatológicos reportaron menos de 0,04 µg/100 g de tomate en todas las muestras analizadas.Conclusiones: El contenido de hierro en el fruto con el tratamiento aminoquelado, es muy superior a los tratamientos control e inorgánico, además es posible obtener tomate biofortificado con minerales como el zinc y hierro aminoquelados, demostrándose que tienen mejor absorción y posibilitando su biodisponibilidad, finalmente, la biofortificación con cianocobalamina no es pertinente en este fruto, pues este nutriente no es almacenado en el tomate.

MATRIX-TYPE CERTIFIED REFERENCE MATERIALS FOR QUALITY CONTROL OF METAL DETERMINATION FROM SOLID ENVIRONMENTAL AND VEGETATION SAMPLES

In the context of monitoring environmental factors, metals are one of the major analytical components. Applying appropriate determination methods and obtaining accurate results is a requirement imposed on environmental laboratories that perform quality control of water, soil, waste, or vegetation. This study presents some examples of certified reference materials for quality control of the results of toxic metal determination from solid environmental and vegetation samples. The analyzed and verified metals were As, Cd, Cr, Cu, Ni, Pb and Zn. The pre-treatment of the samples, the determination methods of metals and the obtained results are also presented. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-EOS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) techniques are suitable for low metal concentrations, while ICP-EOS and Flame Atomic Absorption Spectrometry (FAAS) methods can be used at high concentrations.

Spectrophotometric Determination of Cu(II) in Analytical Sample Using a New Chromogenic Reagent (HPEDN)

The sensitive, accurate and rapid spectrophotometric method that can be used for determination of Cu(II) in the analytical samples using a new chromogenic reagent azo-Schiff base 1-((4-(1-(2-hydroxyphenylimino)ethyl)-phenyl)diazenyl) naphthalene-2-ol (HPEDN). The synthesized new (azo-Schiff base) ligand was complexed with copper(II) and characterized using UV/Vis spectroscopy, IR spectra, 1H-NMR, 13CN-MR spectra, Molar electrical connectivity, and measuring of their melting points. Then obtained complex showed a brown color with maximum absorption at λmax = 500 nm at pH = 9. Beer’s law is obeyed in the concentration in the range of 1.7 to 5.4 μg/mL. The molar absorption and Sandell’s sensitivity values of Cu(II) complex were found to be 0.5038 × 104 L mol–1 cm–1 and 0.0039 μg cm–2, respectively. Structure of the prepared complex was investigated by using the continuous variation, mole ratio method and slope analysis method. The obtained results showed that the complex has (1:2) (M:L) molar ratio and these results showed that this method were more sensitive, more precise and accuracy through the calculation of (Re, Erel, R.S.D)%. The most important interferences were due to, Co2+, Cd2+, Zn2+, Ni2+, Mn2+, Pd2+, Fe3+ and these were studied, and suitable masking agents were used. This method was applied for the determination of Cu(II) in alloy. The obtained results were compared with flame atomic absorption spectrometry method and these results were in a good agreement in these two cases.

Solid Phase Extraction Method for Separation and Pre-concentration of Thallium in Water Samples Using a Novel Adsorbent

In this study, a new and simple column-mode separation method has been proposed for the pre-concentration and removal of trace amounts of thallium(III) (Tl) from water samples. The procedure was based on sorption of Tl(III) ions by a solid phase extraction column filled with 4-[(2-hydroxy, 3-methoxy benzylidine)4-amino]1,2,4-treeazol-5-thione on microcrystalline naphthalene. The determination was performed directly using flame atomic absorption spectrometry (FAAS) method. The main factors affecting the extraction recovery were investigated and optimized. The interference effect of various ions on the determination of Tl(III) was also studied. In optimum conditions, the precision of the proposed method for sample solutions containing 0.2 μg/mL of Tl(III) was 2.0%, and the enrichment factor was found to be 35. The proposed method was evaluated and employed for pre-concentration and removal of Tl(III) from spiked natural (Tap and well) and industrial water samples.

Determination and Identification of Nickel(II) Spectroscopy in Alloy Samples Using Chromogenic Reagent(HPEDN)

A modern and easy procedure performed using the spectrophotometric method and estimating of Ni (II) in alloy samples. Using a ligand 1-((4-(1-(2-hydroxyphenylimino) ethyl)phenyl)diazenyl)naphthalene-2-ol (HPEDN) and a synthesis of the azo-schiff reaction by reaction p-aminoacetophenone with 2-naphtol in first step and reaction of product with 2-aminonaphthol, Ligand and its complex were identification by using UV-Vis. Spectrophotometry (326nm for ligand (HPEDN), 516nm for complex(Ni-HPEDN)), FT-IR, 1H-NMR, and 13C-NMR. The optimal conditions in the complex composition were studied at pH=9, temperature 25°C, and time 15min. The best concentration was found for Ligand (2×10−4 M), Under optimum conditions concentration ranged from (1.1-7.1) μg/mL of Nickel(II) were obeyed Beer‘s Low, with Molar Absorptivity 0.2648×104L.mol−1.cm−1. Limit of Detection(LOD) and Limit of Quantification(LOQ)were 0.3928 and 1.3082μg.mL−1 respectively. The stoichiometric composition of the chelate is 1:2 (Ni:HPEDN). This method is Sensitive, accurate and rapid spectrophotometric method. The results obtained were compared with flame atomic absorption spectrometry method and results are in conformity.

Determination of Copper in Quince Samples with a Matrix Matching Strategy Using Vortex Assisted Deep Eutectic Solvent-Based Emulsification Liquid Phase Microextraction – Slotted Quartz Tube – Flame Atomic Absorption Spectrometry

A vortex assisted deep eutectic solvent-based emulsification liquid-phase microextraction method was developed for the extraction and preconcentration of copper at trace levels followed by determination with slotted quartz tube – flame atomic absorption spectrometry. Various experimental factors were systematically optimized by performing single variant experiments to enhance detection power. Under the optimized conditions, the calibration plot showed linearity in the concentration range from 2.5 to 100 μg L−1. The developed method offered limits of detection and quantification equal to 0.5 and 1.8 μg L−1, respectively. The relative standard deviation (n = 6) for the lowest concentration of the calibration plot was lower than 6.0% which demonstrates good precision. The enhancement in the detection power was 160-fold by the developed vortex assisted deep eutectic solvent-based emulsification liquid phase microextraction – slotted quartz tube – flame atomic absorption spectrometry method. The validity and accuracy of the proposed method were confirmed through recovery experiments on quince samples. Acceptable percent recoveries in the range from 93.6 to 117.6% were obtained.

Determination of Ni(II) in Alloy by Spectrophotometric Method with a new Chromogenic Reagent (IDPBS)

A new chromogenic reagent 4-((imidazole-2-yl)diazenyl)-N-(pyrimidin-2-yl)benzenesulfonamide was synthesized by the reaction between imidazole and Sulphadiazine as azo reagent and used as new spectrophotometric method with highly sensitive to determined Nickel (II). The reagent reacts with nickel(II) in aqueous solution at pH= 7 to form dark- brown colored complex. The reagent and its complex were identified by Fourier transform infrared (FT-IR), Uv-visible,1HNMR, and 13CNMR spectroscopies and investigate the formula and charge of the prepared complex by molar ratio and molar conductivity measurements. The complex shows λmax at 486 nm with a molar absorptivity 0.3299 x 104 L.mo1-1.cm-1 and Sandell’s sensitivity 0.0177μg.cm-2.Beer’s law is obeyed in the concentration range (0.5–7.6μg.mL-1) of Ni (II) with excellent linearity depicted by correlation coefficient value of 0.9995 with a detection limit of 0.1927μg.ml-1. Recovery and relative error values of precision and accuracy of method were found to be R.S.D.% = 0.39221, Re=98.7% and Erel = -1.3% . The nature of the complex showed that (M:L) ratio was 1:2. This method was applied for the determination of Ni(II) in alloy due to Sensitive, accurate, and rapid spectrophotometric method. The results obtained were compared with the flame atomic absorption spectrometry method, and results are in conformity.

Nutritional value of cooked and sous-vide beef: mineral compounds content

AbstractMeat, including beef, is a rich source of minerals in the human diet(1,2). However, different thermal treatments might affect minerals concentration in beef and thus its nutritional value. The aim of the study was to determine the degree of coverage of the demand for minerals by consuming 100 g of steam-cooked and sous-vide beef. Material for the study were semimembranosus muscles (n = 12), cut into 2.5 cm thick steaks, which were subjected to steam cooking to obtain 75°C in geometric centre and sous-vide treatment at 60°C for 4 h. The content of minerals was analyzed by flame atomic absorption spectrometry method (flame:acetylene-air). Percentages of the recommended daily allowance (RDA) of Ca, Cu, Fe, Mg, Zn and the adequate intake (AI) of Mn, K, Na in 100 g of thermal processed beef were determined for adults (males and females, aged 19–50 years) and for children (aged 4–8 years) based on the Institute of Medicine, National Academies, recommendations. The concentration of Ca, Fe, Zn, and Cu was higher in steam-cooked beef, whereas Na and K in sous-vide beef. Thermal processes beef was very good source of Zn and Fe; 100 g of steam-cooked beef satisfied 119% of Zn RDA for children, 54% for males and 74% for females, whereas sous-vide beef 101%, 46% and 63%, respectively. A portion of steam-cooked beef provided 32% of Fe RDA for children, 40% for males and 18% for females, whereas sous-vide beef 21%, 26% and 11%, respectively. The steam-cooked meat was also relatively good source of Cu and provided from 12% RDA (males and females) to 25% (children), whereas sous-vide beef from 10% to 20%, respectively. Thermal processed beef was moderate source for Mg (from 4 to 13% of RDA) and K (from 7 to 9% of AI) and poor source of Ca (up to 0.5% of RDA), Mn (up to 0.3% of AI) and Na (up to 3% of AI). Daily requirements for minerals were satisfied to higher degree by a 100 g portion of steam-cooked beef, which was caused by lower cooking loss than sous-vide samples.