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In the current study, a solid phase extraction (SPE) methodology utilizing sodium ferrite nanoparticles (Na2Fe4O7-NPs; SF-NPs) is presented for the simultaneous determination of heavy metals (HMs) via flame atomic absorption spectrometry (FAAS). SF-NPs were synthesized by an eco-friendly sol–gel auto-combustion method using Tamarindus indica fruit extract as a stabilizing agent. The characterized SF-NPs exhibited a high surface area with uniform distribution, high stability, and a negative surface charge, making it a promising material for excellent adsorption of HMs. The SF-NP-based SPE procedure involved optimizing parameters such as pH, adsorbent dosage, sample volume, eluent composition, volume, and concentration. The developed SF-NP-based SPE method demonstrated low detection limits, i.e., 0.006, 0.008, and 0.009 μg L−1 for the analysis of Cd, Cu, and Pb, respectively. The SF-NP-based SPE methodology was validated by examining certified reference material and real samples, yielding accurate results with good recoveries (>95%) with a relative standard deviation of <5.0%. The developed SF-NP-based SPE method offers a promising approach for the simultaneous determination of Cd, Cu, and Pb in water and food samples, providing an efficient and environmentally friendly analytical tool for monitoring heavy metal contamination. [ABSTRACT FROM AUTHOR]

AbstractMefenamic acid (MNA) treats sports injuries, rheumatoid arthritis, and osteoarthritis. However, improper use/disposal of MNA results in the accumulation of toxic metabolites that may serious disease. The purpose of this study is to fabricate a nano ferrite-based electrochemical sensor for robust, and sensitive determination of MNA. Magnesium ferrite nanoparticles (MgFe4O7-NPs) were synthesized using a green approach using a Mentha leaf extract. The analytical characterization of MgFe4O7-NPs displayed a hexagonal structure and a particle size of less than 21 nm with rough and porous morphology. The synthesized MgFe4O7-NPs were used to fabricate an electrochemical sensor by modifying a glassy carbon electrode (MgFe4O7-NPs/GCE). The cyclic voltammetry (CV) characterization of the electrode confirms excellent redox and diffusion control for electroactive species. Thus, the MgFe4O7-NPs/GCE was used to determine MNA by differential pulse voltammetry (DPV). The results showed a linear relationship between oxidation peak current and concentration of MNA from 10 × 10−9 to 2.30 × 10−4 M (R2 = 0.9918) with a detection limit of 1.12 × 10−9 M. The analytical performance of the fabricated sensor has been evaluated for MNA in blood samples, pharmaceutical tablets, and water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

This work described a plant extract-based synthesis of titanium oxide nanoparticles (D-TiO2–NPs) using Duranta erecta leave extract, followed by the fabrication of its nanocomposite (D-TiO2–NC) with chitosan for adsorptive removal of toxic metals (TMs) cadmium (Cd) and lead (Pb) from water. D-TiO2–NPs and D-TiO2–NC were characterized by various analytical techniques. This study confirmed the porous and rough crystalline nanostructure with different functional groups of chitosan and D-TiO2–NPs of synthesized D-TiO2–NC for feasible excellent adsorptive removal of Cd and Pb. The maximum removal of Cd and Pb was achieved at pH (6), initial concentration of metal ions (30 mg L−1), the content of D-TiO2–NC (50 mg), contact time (30 min), and temperature (45 °C) with adsorption capacities of 147 and 145.5 mg g−1, respectively. The D-TiO2–NC has successfully followed the pseudo-second-order kinetics for the successful removal of Cd and Pb. However, the resulting data followed multilayer adsorption for the removal of Cd while monolayer adsorption for Pb onto the D-TiO2–NC. The findings of the thermodynamic study revealed that the D-TiO2–NC followed the endothermic and spontaneous adsorption process for the adsorption of Cd and Pb. Furthermore, D-TiO2–NC can easily be used several times after washing with diluted HNO3 for the adsorptive removal of Cd and Pb. Moreover, it is quantitatively adsorbed (> 90%) the Cd and Pb from the collected drinking water samples. [ABSTRACT FROM AUTHOR]

An important issue to the earth's atmosphere is the volatilisation of elements such as selenium, from the burning of coal at different temperatures. In the current work, the volatilisation of selenium (Se) during combustion of coal samples at different control temperature range in an electrically controlled furnace was carried out. The coal samples were obtained from various coal fields of Sindh, Pakistan. The duplicate coal samples were combusted in controlled furnace by applying three temperature rounds (200°C, 400°C and 900°C). The ash formed following each temperature round was examined to know the volatilisation contents of Se after burning of coal samples at different temperature. The fractionation of Se in coal ash gained after combustion at 900°C was subjected to three-stage sequential extraction scheme (SES). The obtained data indicated that the total contents of Se in coal samples of block II of Thar coal field (TCF), and Site I and Site II of Lakhra coal field (LCF) were observed in the range of 7.72–14.3, 9.02–16.3 and 8.92–14.2 mg/kg, respectively. It was observed that after the burning of coal samples at 900°C, about 75–81.8% of the total Se was volatised out into atmosphere. [ABSTRACT FROM AUTHOR]

The aim of the current case study is to sequentially assess the heavy metals (HMs) cadmium (Cd), iron (Fe), lead (Pb) and zinc (Zn) in five products (raw juice, bagasse, mud-cake, refined sugar and molasses) along with the effluents of the selected sugar industry (SSI) Sindh, Pakistan. Estimations of daily intake and possible toxic risk of HMs by the consumption of sugar of SSI to end-user (families of SSI workers) of age group of 2.0–5.0, 6.0–15.0, 16.0–30.0 and 31.0–50.0 years were conducted. The high contents of HMs were observed in molasses followed by mud-cake and bagasse (raw waste). The raw juice of sugarcane and refined/white sugar showed the lowest levels of these HMs. The low levels of HMs in effluents of SSI might be to their separation at different stages of sugar processing and refining into the mud-cake, bagasse and molasses. The calculated daily intake of Fe and Zn from refined/white sugar to various study groups was found to be adequate based on the recommended levels by Food and Nutrition Board (FNB). The estimated weekly intake (WI) for Cd and Pb by the consumption of SSI sugar was significantly lower (2–5 times) than the provisional acceptable WI of Cd and Pb by WHO from foodstuff. The potential toxic risk study of Cd and Pb revealed that the studied subjects were not at potential toxic risk by the consumption of SSI sugar. [ABSTRACT FROM AUTHOR]

Fruits are important for human health and researcher makes it possible to learn about their nutrient composition especially essential trace and toxic elemental contents. However, due to complex matrices, the determination of elemental contents in solid and liquid food samples require acid digestion method. Therefore, the current study is designed to develop conventionally acid wet digestion method for detection of electrolytes, Calcium (Ca), Iron (Fe), Magnesium (Mg), Potassium (K), Sodium (Na), essential trace elements, Zinc (Zn) and toxic elements, cadmium (Cd) and lead (Pb) in pulp of different varieties of natural mangoes and juices collected from Hyderabad Sindh, Pakistan, prior to analyse by Atomic Absorption Spectrophotometer. The resulted data indicated that the higher value of Cd was found in a mango variety, MP2 (8.45 µg/L) and its commercially prepared juice (1.30 µg/L). Whereas, significantly higher values of Pb was observed in pulp MP6 than other mangoes sample (p < 0.05) [ABSTRACT FROM AUTHOR]

A simple and novel ultrasonically modified dual-cloud point extraction (Um-DCPE) method has been developed to preconcentrate a toxic heavy metal, lead (Pb2+), in aquifer water of different depths in the region of Thar coalfield, Pakistan, prior to analysed by flame atomic absorption spectrometry (FAAS). The Pb2+ in water samples have been complex with 8-hydroxyquinoline followed by the entrapping in the hydrophobic non-ionic surfactant (Triton X-114). The second step of Um-DCPE involved the addition of 0.5 to 2.0 mol L−1 of HCl/HNO3 (2 mL) and subjected to shaking and centrifugation, separate upper aqueous layers, and subjected for analysis. To check the performance of the proposed method a certified reference material (CRM) of water and spiked standard in a real sample were applied successively. Both LOD and LOQ achieved by the proposed method for Pb2+ were 0.023 and 1.70 μg L−1, respectively. The optimised Um-DCPE method was applied effectively to selected aquifer water samples. The results obtained from the proposed method indicated that the aquifer water samples of different depths have 2 to 3 folds higher Pb2+ values than recommended values of the world health organisation. [ABSTRACT FROM AUTHOR]