Microwave Plasma Atomic Emission Spectroscopy Research Articles

Facile and Bioinspired Approach from Gallic Acid for the Synthesis of Biobased Flame Retardant Coatings of Basalt Fibers.

A sustainable, bioinspired approach to functionalize basalt fibers with an innovative gallic acid (GA)-iron phenyl phosphonate complex (BF-GA-FeP), for the purpose of improving the flame retardancy in composite materials, is developed. BFs were at first pretreated with O3, obtaining surface free hydroxyl groups that allowed the subsequent covalent immobilization of biosourced GA units on the fiber through ester linkages. Phenolic -OH groups of the GA units were then exploited for the complexation of iron phenyl phosphonate, resulting in the target-complex-coated BF fiber (BF-GA-FeP). Microwave plasma atomic emission spectroscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy analyses of BF-GA-FeP highlighted an increase in iron content, modification of fiber morphology, and occurrence of phosphorus, respectively. BFs, modified with a low amount of the developed complex, were used to reinforce a poly(lactic acid) (PLA) matrix in the production of a biocomposite (PLA/BF-FeP). PLA/BF-FeP showed a higher thermal stability than neat PLA and PLA reinforced with untreated BFs (PLA/BF), as confirmed by thermogravimetric analysis. The cone calorimeter test highlighted several advantages for PLA/BF-FeP, including a prolonged time to ignition, a reduced time to flame out, an 8% decrease in the peak heat release rate, and a 15% reduced fire propagating index compared to PLA/BF.

Microwave plasma atomic emission spectroscopy (MP-AES)—A useful tool for the determination of silicon contents in plant samples?

The accurate quantification of silicon (Si) contents in plant materials represents a fundamental prerequisite for agricultural plant-soil system or terrestrial ecosystem studies. Si contents in plants are usually calculated from Si concentrations determined spectroscopically in corresponding plant extracts. Inductively coupled plasma optical emission spectrometry (ICP-OES) is widely used in environmental sciences for Si measurements, because this technique is characterized by relatively high sensitivity and low expenditure of human labor. However, as an ICP-OES instrument is also characterized by relatively high acquisition and running costs, it is not readily available to most laboratories. Microwave plasma atomic emission spectroscopy (MP-AES) might represent a cost-effective alternative to ICP-OES. In our study we compared the results obtained from ICP-OES and MP-AES measurements of Si concentrations in Tiron extracts of husk and straw samples of winter wheat (Triticum aestivum) to evaluate the capability of the MP-AES technique for the determination of Si contents in plant materials. Moreover, we correlated these results with data on plant available Si concentrations in corresponding soil samples as well as phytolith contents in the husk and straw samples to evaluate the performance of MP-AES in biogeochemical Si plant-soil studies. Based on our results we found MP-AES to represent a suitable technique for the reliable determination of Si concentrations in Tiron extracts with negligible matrix effects. Our results clearly indicate that MP-AES represents a promising alternative for all researchers with a focus on biogeochemical Si cycling in general.

Polymer Supported Nitrogen-Bridged Symmetrical Binuclear Dioxidomolybdenum(VI) Complexes and Their Homogeneous Analogues as Potential Catalysts for Efficient Synthesis of 2-Amino-3-Cyano-4H-Chromenes/Pyrans.

Reaction of 2-chloromethyl-1H-benzimidazole with known intermediates (i-iii), prepared from diaminoguanidine hydrochloride with salicylaldehyde, 5-bromosalicylaldehyde or 3,5-di-tert-butylsalicylaldehyde, in the presence of triethylamine (NEt3) led to the formation of benzimidazole appended new ligands, H4L1-H4L3 (I-III). The homogeneous nitrogen-bridged symmetrical binuclear complexes, [(MoVIO2)2(L1)(H2O)2] (1), [(MoVIO2)2(L2)(H2O)2] (2) and [(MoVIO2)2(L3)(MeOH)2] (3) have been isolated by reacting these ligands with [MoVIO2(acac)2] in a 1 : 2 molar ratio in refluxing methanol. Using 1 : 1 (ligand to Mo precursor) molar ratio under above reaction conditions resulted in the corresponding mononuclear complexes, [MoVIO2(H2L1)(MeOH)] (4), [MoVIO2(H2L2)(H2O)] (5) and [MoVIO2(H2L3)(MeOH)] (6). The binuclear heterogeneous compounds [(MoVIO2)2(L1)(DMF)2]@PS (PS-1), [(MoVIO2)2(L2)(DMF)2]@PS (PS-2) and [(MoVIO2)2(L3)(DMF)2]@PS (PS-3) have been obtained by immobilization of 1-3 onto chloromethylated polystyrene (PS) beads. All synthesized ligands, homogeneous as well as supported compounds have been characterized by elemental analyses and various spectroscopic methods. Single crystal X-ray diffraction study of complexes 1 and 3 confirms their nitrogen-bridged symmetrical binuclear structures while 4 is mononuclear. Heterogeneous compounds (PS-1-PS-3) have further been studied by microwave plasma atomic emission spectroscopy, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy along with energy dispersive spectroscopy. These compounds (homogeneous and heterogeneous) were explored for catalytic applications to one-pot multicomponent reactions (MCRs) for efficient synthesis of biologically active 2-amino-3-cyano-4H-chromenes/pyrans (21 examples). Optimising various reaction parameters helped in achieving as high as 97 % yields of products. Though, only half equivalent of the binuclear complexes (1-3) was required compared to mononuclear analogues (4-6) to achieve comparable yields, heterogeneous catalysts have an added advantage due to their stability and recyclability. Suitable reaction mechanism has also been proposed based on isolated intermediates.

Evaluation of Extractants for Determination of Micronutrients in Soils of South Gujarat, India

An experiment was conducted at Department of Soil Science and Agricultural Chemistry, Navsari Agricultural University during the year 2018-19. The methods of micronutrients determination were (i) extracted through diethylene triamine penta acetic acid (DTPA) (ii) extracted through ammonium bicarbonate- diethylene triamine penta acetic acid (AB-DTPA) (iii) extracted through Neubauer. The methods of micronutrients were evaluated through method validation parameters like linearity, sensitivity of instruments, precision and predictability. The available micronutrients determined from the sample soils were correlated with soil physico-chemical properties to know the relationship of these properties with available micronutrients. The linearity study of the series of micronutrients standard were measured through different methods of micronutrient determination. These measured values showed linear relationship with reference values. The coefficient of determination (R2) for all the methods was > 0.90. The precision was determined by relative standard deviation (RSD) (%) of different micronutrient methods which were in the range of 1.834 to 19.11 %. All the studied methods of copper, iron, zinc and manganese determination, AB-DTPA extractant method has highly significant and positive correlation with nutrient uptake by wheat on Microwave Plasma Atomic Emission Spectroscopy (MP-AES) instrument. Organic C and sand content of soil have positive correlation with micronutrients availability. While pH, EC, CEC, CaCO3, silt and clay content of soil have negative correlation with available micronutrients.

Simultaneous Determination of Mineral Nutrients and Toxic Metals in M. stenopetala from Southern Ethiopia: A Comparative Study of Three Cultivating Areas Using MP-AES.

In this study, for the first time, the levels of thirteen micro- and macromineral nutrients in the leaves, seeds, and supportive soil of Moringa stenopetala (M. stenopetala) were simultaneously determined using microwave plasma atomic emission spectroscopy (MP-AES). The samples were collected during the arid season, in 2019 from the three main M. stenopetala growing areas in southern Ethiopia (Chano Mile Kebele, Nechisar Kebele, and Konso Special Woreda). A novel digestion method for leaf and seed samples was developed using an optimized acid mixture (2.5 : 0.75 : 0.5 of HNO3, HClO4, and H2O2) at 240°C for 2 hrs and 30 min, resulting in clear and colorless solutions. The method makes the digestion process more efficient by minimizing the reagent volume, reducing digestion temperature and time, and simplifying the overall procedure. The efficiency of the optimized procedure was validated by spiking experiments, and the percentage recovery ranged between 94 and 110%. Under optimized experimental conditions, higher concentrations of essential minerals (K, Na, Ca, and Mg) were observed in the plant leaf and seed samples from the three areas. In addition, significant amounts of trace elements (Fe, Mn, Zn, and Cu) were also found. Importantly, no traces of the toxic elements (Cd and Pb) were detected in any of the analyzed samples, suggesting that the leaves and seeds of M. stenopetala are valuable sources of both micro- and macromineral nutrients and are safe from toxic metals. From a dietary perspective, the seed contains almost comparable concentrations of minerals as the leaves. As a result, the seeds of M. stenopetala can serve as an alternative source of minerals and play a role in overcoming the current global food crisis, particularly in the dry season. Analysis of variance at a 95% confidence level revealed significant differences in the levels of all mineral nutrients between the three sample means except K, Ca, Co, and Cu. Generally, the developed method includes an innovative digestion procedure that minimizes reagent consumption, operates at lower temperatures, and requires shorter digestion times, thereby optimizing resource utilization and maintaining analytical accuracy. Notably, the absence of toxic elements in the MP-AES procedure highlights the safety and reliability of M. stenopetala leaves and seeds as valuable, contamination-free sources of essential nutrients.

Evaluation of Doped Polyaniline as Potential Sensing Materials and/or Absorbents For Styrene and Phthalates in Aqueous Solutions

AbstractThe removal and detection of toxic analytes, including monomers and plasticizers, is important for both health and the environment. Potential absorbents and/or sensing materials are successfully made from polyaniline (PANI) and PANI doped with 10 wt.% of aluminum oxide (PANI‐Al2O3) and titanium dioxide (PANI‐TiO2). The amount of metal oxide incorporated into the surface layers of the polymer and the total amount incorporated are confirmed by energy dispersive X‐rays (EDX) and microwave plasma‐ atomic emission spectroscopy (MP‐AES), respectively. All three materials are evaluated as potential sensing materials and/or absorbents for styrene, monobutyl phthalate (MBP), and dibutyl phthalate (DBP) at 100 ppm in aqueous solutions. It is found that incorporating TiO2 into PANI improved both the sensitivity and selectivity to styrene, making PANI‐TiO2 a good absorbent and potential sensing material for styrene. Additionally, incorporating Al2O3 into PANI improved the sorption to MBP, but reduced the selectivity. As a proof‐of‐concept, the responses of the polymeric nanocomposites are combined and analyzed using principal component analysis (PCA) as such an algorithm. The output reveals good separation of the responses to each analyte, thereby demonstrating how sensing materials with poorer selectivity can be used together to overcome limitations in selectivity.

Geographical origin identification of mandarin fruits by analyzing fingerprint signatures based on multielemental composition

Given rising traders and consumers concerns, the global food industry is increasingly demanding authentic and traceable products. Consequently, there is a heightened focus on verifying geographical authenticity as food quality assurance. In this work, we assessed pattern recognition approaches based on elemental predictors to discern the provenance of mandarin juices from three distinct citrus-producing zones located in the Northeast region of Argentina. A total of 202 samples originating from two cultivars were prepared through microwave-assisted acid digestion and analyzed by microwave plasma atomic emission spectroscopy (MP-AES). Later, we applied linear discriminant analysis (LDA), k-nearest neighbor (k-NN), support vector machine (SVM), and random forest (RF) to the element data obtained. SVM accomplished the best classification performance with a 95.1% success rate, for which it was selected for citrus samples authentication. The proposed method highlights the capability of mineral profiles in accurately identifying the genuine origin of mandarin juices. By implementing this model in the food supply chain, it can prevent mislabeling fraud, thereby contributing to consumer protection.

Heavy metal contamination and health risk assessment of horticultural crops in two sub-cities of Addis Ababa, Ethiopia

This particular study was aimed to establish the level of heavy metals in different horticultural crops cultivated by irrigation and the soil in two sub-cities of Addis Ababa, Ethiopia, and quantitatively assess the health treat they pose for the consumer. A total of 151 vegetable samples comprised of lettuce (Lactuca sativa), cabbage (Brassica oleracea var. capitate), cucumber (Cucumis sativus), potato (Solanum tuberosum), parsley (Petroselinum crispum), Swiss chard (Beta vulgaris subsp. vulgaris), beetroot (Beta vulgaris), green onion (Allium porrum L.) and 28 soil samples were collected for this study. Six toxic elements were analyzed using microwave plasma atomic emission spectroscopy (MP-AES) after microwave assisted digestion of the samples. The concentrations of examined trace elements in vegetables (mg/kg) were found in the range of 5.50–93.00 for zinc; below detection limit (BDL)− 18.50 for copper; BDL-2.50 for nickel; BDL-17.00 for lead; 5.00–4256.50 for manganese and 22.00–8708.00 for iron. Considering the mean Pb content values, all vegetables exceeded the maximum permissible level set by the joint FAO/WHO commission in both irrigation sites. In case of Mn parsley, swiss chard, and green onion all from site two exceeded the maximum allowable values. With the exception of potato from irrigation site one, all vegetables exceeded the maximum permissible limit set for Fe concentration and out of which parsley, swiss chard, and green onion, all from site two, exceeded by more than double amount. The same trend is observed for the concentration of Mn and Fe in the soil samples. In fact, in both irrigation sites their concentration exceeded the allowable limits set by United Nation Environment Program (UNEP) for agricultural soils. The metal pollution load index revealed that in most of the vegetables studied the overall pollution load of trace metals were higher in Kolfe Keranyo irrigation site. The risk assessment study using indices like estimation of daily/weekly dietary exposure, hazard quotient and metal pollution load index all suggested consumption of the studied vegetables poses a significant health risk for the consumer. For adults the calculated target hazard quotient for the trace element Pb is higher than 1 (one) for all of studied vegetables ranging from 11.086 (cucumber) to 17.881 (beetroot) with a 98.216% and 98.464% contribution to the hazard indices, respectively. For a child consumer, Mn showed a higher target hazard quotient vales ranged from 0.0107 (cucumber) to 0.0495 (green onion) with a 70.86% and 88.85% contribution to the total hazard indices, respectively. The soil pollution indices also indicated that the degree of metal enrichment in soils and sediments are higher than the allowable limits. Therefore, a prompt action is required to curb the problem and ensure the public safety along the food system line.

Speciation analysis of inorganic Sb leached from InSb thin films by hydride generation–microwave plasma-atomic emission spectroscopy

Speciation analysis of inorganic Sb leached from InSb thin films by hydride generation–microwave plasma-atomic emission spectroscopy

COMPARATIVE RISK ASSESSMENT OF SOME TOXIC ELEMENTS’ CONTENTS IN DOMESTIC AND IMPORTED TOMATO PASTES AND KETCHUP IN NIGERIAN MARKETS

Although tomato consumption, whether as tomato paste or tomato ketchup, offers several health advantages, the future prognostic indicators hypothesize the disappearance of these gains due to heavy metal poisoning. Therefore, using the Microwave Plasma Atomic Emission Spectroscopy (MP-AES) technique, this study examined and compared the amounts of arsenic (As), nickel (Ni), cadmium (Cd), lead (Pb), and mercury (Hg) in locally produced and imported tomato pastes and ketchup sold in Nigerian markets. The mean concentrations of these targeted elements in tomato pastes and ketchup (in mg.kg-1) respectively are presented as follows: As (domestic & imported: < LOQ), Ni (domestic:0.308, 0.289; imported: 0.271, 0.267), Cd (domestic:0.088, 0.075; imported:0.078, 0.083), Pb (domestic: 0.121, 0.102; imported:0.128, 0.136) and Hg (domestic and imported: <LOD). As, Ni, and Cd contents in domestic and imported tomato pastes and ketchup samples and daily intake rates (DIR) were within acceptable levels recommended by regulatory agencies. Except when combined metals’ hazard quotients are considered, which may pose serious health concern, individual’s metal effect constitutes a negligible health risk.

Gold Nanoparticles Inhibit Extravasation of Canine Osteosarcoma Cells in the Ex Ovo Chicken Embryo Chorioallantoic Membrane Model.

Canine osteosarcoma (OS) is an aggressive bone tumor with high metastatic potential and poor prognosis, mainly due to metastatic disease. Nanomedicine-based agents can be used to improve both primary and metastatic tumor treatment. Recently, gold nanoparticles were shown to inhibit different stages of the metastatic cascade in various human cancers. Here, we assessed the potential inhibitory effect of the glutathione-stabilized gold nanoparticles (Au-GSH NPs) on canine OS cells extravasation, utilizing the ex ovo chick embryo chorioallantoic membrane (CAM) model. The calculation of cells extravasation rates was performed using wide-field fluorescent microscopy. Transmission electron microscopy and Microwave Plasma Atomic Emission Spectroscopy revealed Au-GSH NPs absorption by OS cells. We demonstrated that Au-GSH NPs are non-toxic and significantly inhibit canine OS cells extravasation rates, regardless of their aggressiveness phenotype. The results indicate that Au-GSH NPs can act as a possible anti metastatic agent for OS treatment. Furthermore, the implemented CAM model may be used as a valuable preclinical platform in veterinary medicine, such as testing anti-metastatic agents.

Evaluations of Sisal Fiber as Biosorbent for online Preconcentration and Determination of Cu and Mn coupled to MP AES using the Analytical Greenness Metric Approach

Biorsorbents can be used to pack minicolumns for the preconcentration of trace elements and thus improve the detection limits of some techniques. A biosorbent is efficient when presents binding sites as carbonyls, amines, and carboxylic groups, among others. Thus, natural materials as the sisal fiber (Agave sisalana) may be a good candidate. Sisal fiber demonstrated good performance for Cu preconcentration when it was impregnated with alizarine fluorine blue (AFB). However, very good results were reported for the first time by our group with this column, without the use of additional reagents for both, Mn and Cu determinations in water samples by using microwave plasma atomic emission spectroscopy (MP AES). In this paper a comparison of the sisal fiber preparation with and without impregnation with AFB is presented and discussed in terms of the figures of merit, including precision, trueness, limits of detection and quantification. In addition to that, the number of determinations without the need of replacement of the solid phase was evaluated. Results demonstrated that the impregnation of sisal fiber with AFB does not leads to an improvement in the analytical performance. Analytical Greenness Metric Approach (AGREE) was used to evaluate the greenness of both methods and results obtained were similar. Despite this, the method without impregnation of the fiber has some remarkable advantages, that contributes to Green Analytical Chemistry (GAC), related to the lifetime of the sorbent, not considered in the AGREE tool.

Mineral Composition of Cassava Leaves (Manihot esculenta Crantz) Harvested at Various Periods and Growth Stages, and Its Changes during In Vitro Simulated Gastrointestinal Digestion

Total and bioaccessible minerals in edible cassava (Manihot esculenta) leaves (ECLs) harvested at different maturity stages and seasons were assessed by microwave plasma atomic emission spectroscopy. The results showed significant (p < 0.05) variations at maturity stages across seasons. A two-way analysis also showed significant effects of the variety and period of harvest. However, the highest content of total minerals was obtained at 6 months after planting (MAP), except for Mn, Zn, and Cu. The total macromineral contents (mg/100 g) were K (64.14–3532.94), Ca (34.19–543.57), Mg (25.84–365.03), and Na (73.84–727.70), and micromineral contents (μg/100 g) were Mn (779.98–7550.89), Zn (55.47–997.70), Cu (31.76–7288.18), and Fe (8.57–30.85 mg/100 g). The bioaccessibilities of minerals were Fe (0.56–63.85%), Mn (0.49–63.64%), and Zn (1.77–60.82%), while bioaccessibilities of Ca (0.22–48.30%) and Na (1.53–46.80%) were low. Besides, the bioaccessibility of minerals at 6MAP was lower than that in advanced stages of maturity. The variety TMS 96/1414 showed the highest bioaccessible minerals (Mn 93.35 μg/100 g and Cu 53.01 μg/100 g) at 9MAP, while IRAD4115 presented the highest bioaccessible minerals (Fe 7.79 μg/100 g and Zn 133.64 μg/100 g) at 9MAP and 12MAP, respectively. A significant (p < 0.01) positive correlation was found between the total and bioaccessible mineral contents. The study reveals that minerals in ECLs harvested at different stages were bioaccessible, with high values at mature stages, which can be recommended as mineral sources for consumers.

Pd(II) Schiff base complex anchored on MCM-41, a reusable catalyst for the Heck reaction

A Palladium (II) Schiff base complex was implanted on the surface of MCM-41 to fabricate a simple and reusable catalyst using post-grafting methodology. The surface of MCM-41 initially modified with 3-chloropropyltriethoxysilane (CPTES), followed by the Schiff base ligand (PAL) and on reacting with PdCl2 results in the formation of MCM@CP@PAL@Pd complex. Characterization of the designed heterogeneous catalyst by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Microwave Plasma Atomic Emission Spectroscopy (MP-AES) and Brunauer–Emmett–Teller (BET) techniques indicated successful grafting of Palladium (II) complex inside the hexagonal channels of MCM-41.The MCM@CP@PAL@Pd catalyst was used for a good range of Heck reactions using different aryl halides with styrene or alkyl acrylate esters. The catalyst has low metal content, provides magnificent yield (95%) in a short time period (20 min), displayed excellent structural and chemical stability and can be reused seven times without remarkable change in its catalytic efficiency.

Determination Of Exchangeability Cations (Ec), Texture And C-Organic Content In Mineral Soils and Peat

EC or can be called exchangeable cation is a nutrient cation found in the soil. This is useful for indicating the degree of alkaline saturation, which indicates that the more saturated the soil base, the more fertile the soil will be. This study aims to obtain supporting information to obtain soil conditions that show the quality of the land as a growing medium. The method used for texture analysis on this soil refers to SNI 3423.03:1994 and C-Organic content analysis refers to SNI 4720.13:1998. The cation level test was carried out using NH4OAc solution with a Microwave Plasma Atomic Emission Spectroscopy (MP-AES) instrument. This instrument has a principle, namely atomic emission which is a form of energy produced by an atom when it returns to the ground state (Ground State) of the excited state (Excitation State). The results of this cation level test with analyte concentrations of K, Ca, Na and Mg with sample code SJ2022-01826 successively 0.65; 3,59; 0.82 and 0.94. The amount of cation content in fertile soil is worth at least 6 mg / L in accordance with the provisions of the Chemical Technical Manual.

Major and heavy metals contents and health risk assessment of pumpkin peel, flesh and seed by microwave plasma-atomic emission spectroscopy

ABSTRACT. The aim of this study was to determine the levels of major (Na, Mg, K, Ca) and heavy (Cr, Mn, Fe, Ni, Cu, Zn, Cd) metals and health risk assessment of the peel, flesh and seed of pumpkins cultivated in Ethiopia, using microwave plasma-atomic emission spectrometry. Dried powdered samples (0.5 g) were wet digested with 69% HNO3 and 30% H2O2 in microwave digester. The percent recovery for the three parts of pumpkin samples were 90-110%. The mean concentration of metals in pumpkin peel, flesh, seed samples, respectively, were K (27806±9767, 29531±2452, 10667±1133), Ca (5267±2092, 3190±900, 2919±397), Mg (4716±469, 848±349, 4668±413), Fe (158±29, 111±46, 225±56), Na (167±116, 63.1±15, 171±123), Mn (28.9±1.4, 9.61±3.2, 33.4±4.9), Zn (24.2±4.4, 10.6±4.0, 67.5±12.3), Cu (8.14±1.1, 15.1±9.3, 10.8±0.9), Ni (3.79±2.4, 2.14±1.3, 3.44±2.8), Cr (0.28±0.1, 0.36±0.2, 0.69±0.1), Cd (0.24±0.1, 0.46±0.1, 1.39±0.2) mg/kg. The hazard index (HI) of pumpkin flesh and seed indicated ingestion of pumpkin is safe from non-carcinogenic risk. The total cancer risk (CR) due to consumption of pumpkin flesh and seed through Cr and Cd from the three sampling sites are in the range 1.1 x 10-4 -1.8 x 10-4, indicating a non-risk of exposure to cancer due to the consumption of pumpkin grown in the sampling areas.&#x0D; &#x0D; KEY WORDS: Pumpkin, Mineral content, Health risk, Microwave plasma-atomic emission spectrometry&#x0D; &#x0D; Bull. Chem. Soc. Ethiop. 2023, 37(3), 533-551. &#x0D; DOI: https://dx.doi.org/10.4314/bcse.v37i3.1

Glutathione-S-transferase (GSTM1 and GSTT1) polymorphism and lead toxicity in individuals environmentally exposed to lead

Genetic variation in enzymes involved in metal detoxification could have influence on susceptibility to lead-induced oxidative stress. The present study aimed at evaluating the effects of genetic variation of Glutathione-S- transferase gene on oxidative stress markers (GSH, SOD, CAT and MDA) among individuals environmentally exposed to lead. GSTM1 and GSTT1 null homozygous genotypes were determined by polymerase chain reaction. Blood lead levels were determined using Microwave Plasma Atomic Emission Spectroscopy (MP- AES-Agilent 4210 USA). Activities of superoxide dismutase, catalase and glutathione levels were assayed using Cayman’s commercial kits. The study found mean blood lead levels of the study subjects of 78.16± 5.79µg/dl with range from 26.6 to 191.0 µg/dl. The frequencies of GSTM1 and GSTT1 null genotypes were 23% and 50.8% respectively. The frequency was high in individuals with blood lead levels greater than 70µg/dl. Significant decreased activity of antioxidant enzymes (SOD and CAT), glutathione levels and concomitant increased of MDA concentrations were observed in individuals with GSTM1 and GSTT1 null genotypes. Therefore, findings from this study were enough to infer a causal relationship between environmental exposure to lead and oxidative stress. Individuals who are homologous null at GSTM1 and GSTT1 loci predispose to increased risk of multi-organs toxicity from environmental exposure to lead.

Comparative study of some macro &amp; micro elements in milk samples from Abuja, Nigeria using microwave plasma atomic emission spectroscopy (MP-AES) and flame atomic absorption spectroscopy (F-AAS) methods

A comparative study was carried out for the determination of calcium, magnesium, iron and zinc contents in two brands of powdered milk samples, using the Microwave Plasma Atomic Emission Spectroscopy (MP-AES) and Flame Atomic Absorption spectroscopy (F-AAS) methods. The powdered milk samples were collected and placed in a muffle furnace at 550°C for 6 hours, and the ash contents obtained was used for the sample preparation. The percentage recoveries for the spikes were as follows: for MP-AES determination; the recoveries for the milk samples were within the range (116.9 – 163.1%) for calcium; (51.8 – 78.8%) for magnesium; (110.9 – 125.4%) for iron; (90.7 – 92.9%) for zinc. For FAAS determination; the recoveries for the milk samples were within the range (51.1 – 83.6%) for calcium; (52.2 – 61.9%) for magnesium; (77.7 – 84.8%) for iron; (46.5 – 71.7%) for zinc. The percentage recoveries showed a better recovery with MP-AES than the F-AAS method. The analysis of variance conducted using One way ANOVA method shows that there is no significant difference between the two methods used for the analysis, as the P-values (calculated probability) obtained were higher than 0.05. The values obtained for Ca, Mg, Fe and Zn content shows that only Ca was found to be within WHO/FAO standard, while Mg, Fe and Zn were found to be below the WHO/FAO standard. It is highly recommended that a 100g of any of the powdered milk used for the research work be consumed per day in order to meet up with the RDA per day, or other sources of these elements to be considered.Â

Preparation and structure analyses of Sn-bentonite for pertechnetate removal

Tin (Sn) -bentonite was prepared by ion exchange method from Ca-bentonite. For the ion exchange process, tin-chloride (SnCl2) solution was prepared from metallic tin, and the tin concentration was determined by Microwave Plasma Atomic Emission Spectroscopy (MP-AES). Sn-bentonite was characterized by X-ray fluorescence spectrometry (XRF), X-ray powder diffraction (XRPD), X-ray photoelectron spectroscopy (XPS) and 119Sn as well as iron-57 (57Fe) Mössbauer spectroscopy. 119Sn Mössbauer spectroscopy and XPS undoubtedly revealed both Sn+2 and Sn+4 ions in Sn-bentonite. SnII was attributed to be incorporated into the interlayer space while SnIV located partly in the octahedral position and in the interlayer space of montmorillonite. The removal of radioactive pertechnetate anion (99mTcO4-) was studied on Sn-bentonite in aqueous and artificial urine media. Based on the measurement results, 99mTcO4- ion can be removed, in case of aqueous media, the equilibrium is reached after 5 mins (x = 99.9 ± 0.01%, k = 4.2 ± 0.83 1/min) (Buzetzky et al., 2019), while in the case of urine media the equilibrium is reached after 30 mins (x = 59.1% ± 2.7, k = 0.18 ± 0.05 1/min). Pertechnetate anoin sorption on tin-bentonite is a (Sn(II/IV)-TcO4-) redox reaction. Thus, Sn-bentonite can be a suitable sorbent for radioactive waste management.

Analysis of Micro-Contaminants in Solid Particles from Direct Injection Gasoline Vehicles

Exhaust emissions from vehicles are the subject of numerous studies and legal acts. In the European Union, exhaust emissions are regulated by “Euro” emission standards, which limit emissions of gaseous pollutants such as CO, CO2, HC, and NOx, as well as the particulate matter (PM) and particle number (PN). Solid particles consist of a number of micro-contaminants, inter alia polycyclic aromatic hydrocarbons (PAHs) and their nitrated and oxygenated derivatives. Despite their highly mutagenic and carcinogenic character, these micro-contaminants are not regulated in Euro emissions standards. This paper presents both a general discussion of the phenomenon of particulate formation in and emission from direct injection gasoline engines, as well as a wide range of results on the subject. The subject of the micro-contaminants in solid particles from modern gasoline vehicles is explored. The samples of solid particles were collected from 11 groups of vehicles according to the WLTP test methodology. Solid particles from gasoline vehicles were analyzed via various analytical techniques, including ion chromatography (IC) to measure selected anion concentrations, gas chromatography with mass spectroscopy (GC-MS) to study 16 PAHs and selected PAH derivatives, scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) for images and elemental composition, and microwave plasma atomic emission spectroscopy (MP-AES) for qualitative screening analysis of 19 elements. The study of non-regulated compounds is crucial in efforts to establish the influence of solid particles on health and the environment. Furthermore, extended studies can provide a basis for further research on vehicle emissions or other fields, such as medicine or material engineering.