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1.
RSC Adv ; 13(27): 18734-18747, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37346942

RESUMO

In this paper, for the first time, we report the use of a new carbon paste electrode based on a low-cost pencil graphite powder modified with polyaniline (PANI) and green synthesized copper oxide nanoparticles using Ficus elastica extract as a sensor for Cd2+, Pb2+, and Hg2+. The elaborated electrode was characterized by FT-IR spectroscopy, field-emission gun scanning electron microscopy (FEG-SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and simultaneous thermal analysis (TGA/DSC). The electrochemical behavior of the sensor was evaluated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy techniques. According to CV, as well as square wave voltammetry (SWV) results, it was found that the CuONPs/PANI-CPE sensor was able to determine very low concentrations of Cd2+, Pb2+, and Hg2+ in HCl (0.01 M) either in single metal or in multi-metal solutions with a high sensitivity. Furthermore, Cd2+, Pb2+, and Hg2+ simultaneous detection on CuONPs/PANI-CPE achieved very low limits of detection (0.11, 0.16, and 0.07 µg L-1, respectively). Besides, the designed sensor displayed a good selectivity, reproducibility, and stability. Moreover, CuONPs/PANI-CPE enabled us to determine with high accuracy Cd2+, Pb2+, and Hg2+ traces in environmental matrices.

2.
Biol Trace Elem Res ; 201(4): 1704-1716, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35666385

RESUMO

During the recent decades, adverse effects of unexpected contaminants, such as heavy metals on raw cow milk quality, have threatened human health. The objective of this study was to determine heavy metal levels in raw milk collected from autochthonous bovine breeds in the eastern region of Algeria. Eighty-eight pooled milk samples were analyzed using atomic absorption spectrometry for Pb, Cd, Cr, Cu, Ni, Fe, and Zn, and dietary risks were estimated for infants, children, and adults with minimum, average, and maximum milk consumption scenarios. Results revealed that Pb (0.94 ± 0.49 mg/kg), Cd (0.03 ± 0.01 mg/kg), and Cu (0.14 ± 0.08 mg/kg) levels in all analyzed samples were higher than their corresponding maximum residue levels (MRLs). The task hazard quotient (THQ) values suggest potential risk for infants in the three scenarios from Pb, Cd, and Cr; for children in the three scenarios from Pb and in the high scenario from Cr; and for adults in the medium and high scenarios from Pb. The hazard index (HI) values were higher than 1, and the contributions of each metal to the overall HI followed a descending order of Pb, Cr, Cd, Ni, Zn, Cu, and Fe with values of 68.19%, 15.39%, 6.91%, 4.94%, 3.42%, 0.88%, and 0.28%, respectively. Our results indicated that there may be a potential risk of heavy metals, especially Pb, for infants through raw cow milk consumption. Moreover, data actualization and continuous monitoring are necessary and recommended to evaluate heavy metal effects in future studies.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , Feminino , Animais , Bovinos , Humanos , Leite/química , Cádmio/análise , Argélia , Chumbo/análise , Metais Pesados/análise , Medição de Risco , Monitoramento Ambiental , Poluentes do Solo/análise
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 253: 119579, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33611219

RESUMO

In view of the anticancer effect of nitrosoureas a set of four new N-(2-chloroethyl)-N-nitrosourea (CENU) derivatives was synthesized. An in silico absorption, distribution, metabolism, excretion and toxicity (ADME/Tox) prediction study revealed that the CENU derivatives satisfied all the required criteria for oral administration and introduced them as remarkable anticancer candidates in the central nervous system (CNS). A comparative solvatochromic study including the Kamlet-Taft, Catalán and Laurence models indicated that the solvatochromic behavior of the CENUs depended on both, unspecific and specific solvent-solute interactions. In detail, the solvatochromic effect of the solvent polarity on the absorption and emission maxima was significant for all CENUs, whereas the solvatochromic effect of the solvent's ability to donate or accept hydrogen bonds on the absorption and emission maxima was critically dependent on the electron density of the N'-aryl group. From the solvatochromic comparison method, excellent correlations (r ≥ 0.890) were obtained between the ADME parameters and the solvatochromic regression coefficients obtained by the Catalán model. As potential stabilizers, inclusion complexes of the investigated CENU derivatives with ß-cyclodextrin (ß-CD) were also explored. The spectrofluorimetric host-guest experiments included double-reciprocal Benesi-Hildebrand plots as well as the molar ratio and continuous variation plots (Job's plots), which established a 1:1 ß-CD to CENU binding stoichiometry and relatively high affinities of ß-CD for CENU derivatives.


Assuntos
beta-Ciclodextrinas , Simulação por Computador , Ligação de Hidrogênio , Soluções , Solventes
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