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1.
Environ Sci Pollut Res Int ; 28(29): 40022-40034, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33770354

RESUMO

A new nickel ion, magnetic imprinted polymer was fabricated through the precipitation polymerization process, using amine-functionalized silica-capped iron oxide particles as a core material, and 4-vinyl pyridine as complexing agent methacrylic acid as functional monomer. The resulted magnetic adsorbent was employed to eliminate toxic Ni2+ ions from industrial wastewater. The different parameters were optimized, such as pH, shaking speed, and adsorbent dose, to obtain the maximum adsorption capacity. The synthesized material showed high selectivity coefficient for Ni+2 ions in the presence of other competitive ions and followed pseudo-second-order kinetics and Langmuir isotherm. A good adsorption capacity of 158.73 mg g-1 was obtained at optimized pH 6 in the concentration of 5 mg L-1 nickel ions aqueous solution. The limit of detection, quantification, and the percent relative standard deviation was found to be 0.58, 1.93, and 3.4%. This proves the excellent performance of prepared magnetic Ni(II) ion-imprinted polymer for selective detoxification of Ni2+ ions from real aqueous samples. Due to tunable magnetic properties, the prepared MMIPs are highly selective and sensitive and highly porous in nature; due to excellent magnetic properties, there is no need for centrifugation. Just use external magnetic field, it has good reusability. Showing preparation of Ni (II) imprinted magnetic polymer.


Assuntos
Níquel , Polímeros , Adsorção , Cinética , Fenômenos Magnéticos , Magnetismo
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 877-85, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25280335

RESUMO

A green and sensitive temperature controlled dispersive liquid-liquid microextraction (TIL-DLLME) methodology based on the application of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim][PF6], as an extractant solvent was proposed for the preconcentration of trace levels of aluminium (Al(3+)) in scalp hair samples of Alzheimer's (AD) patients, prior to analyzing by flame atomic absorption spectrometry (FAAS). The Al(3+) was complexed with 8-hydrooxyquinoline (oxine) (L1) and 3,5,7,2'-4' pentahydroxy flavone (morin) (L2) separately and then extracted by IL at temperature (50±2.0°C). Some effective factors that influence the TIL-DLLME efficiency such as pH, ligands concentrations, volume of IL, ionic strength, and incubation time were investigated and optimized by multivariate analysis. In the optimum experimental conditions, the limit of detection (3s) and enhancement factor were 0.56 µg L(-1), 0.64 µg L(-1) and 85, 73 for both ligands, respectively. The relative standard deviation (RSD) for six replicate determinations of 100 µg L(-1) Al(3+) complexed with oxine and morin were found to be 3.88% and 4.74%, respectively. The developed method was validated by the analysis of certified reference material of human hair (NCSZC81002).and applied satisfactorily to the determination of Al(3+) in acid digested scalp hair samples of AD patients and healthy controls. The resulted data shows significant higher level in scalp hair samples of AD male patients with related to referents of same age and socioeconomic status.


Assuntos
Alumínio/análise , Doença de Alzheimer/diagnóstico , Cabelo/química , Microextração em Fase Líquida , Ácidos/química , Idoso , Alumínio/química , Calibragem , Estudos de Casos e Controles , Transtornos Cognitivos/diagnóstico , Flavonoides/química , Humanos , Ligantes , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Análise Multivariada , Oxiquinolina/química , Reprodutibilidade dos Testes , Couro Cabeludo , Espectrofotometria Atômica
3.
Biol Trace Elem Res ; 160(2): 197-205, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24973874

RESUMO

There is accumulative evidence that the metabolism of iron (Fe) and copper (Cu) is altered in human due to infections, indicating that both elements have roles in pathogenesis and progress of viral diseases. In the present study, the correlation of Cu and Fe was evaluate in biological samples (serum and scalp hair) of hepatitis C (hepatitis C virus (HCV)) patients of both genders at different stages. For comparative study, the scalp hair and serum samples of healthy individuals of same age group (30-50 years) and socioeconomic status were collected. The biological samples were analyzed for Fe and Cu by atomic absorption spectroscopy after microwave-assisted acid digestion. The validity and accuracy of methodology were checked by certified reference materials of same matrixes. The levels of Cu and Fe in biological samples were enhanced in hepatic disorder patients, including acute (after diagnosis test, anti-HCV sero-positive) hepatic fibrosis and liver cirrhosis as compared to healthy referents. The difference was significant (p < 0.01) in the case of liver cirrhotic patients. It was observed that the data of Cu and Fe in referents and patients of both genders had normal distributions. The inter-elemental correlation (r) among Cu vs Fe in serum and scalp hair samples of referents and patients were not significant in both genders (p > 0.1) except in the first stage of HCV (p < 0.1). It was concluded that the increase of Cu and Fe content in human body seems to contribute to the development of cirrhosis in patients with viral hepatitis C.


Assuntos
Cobre/análise , Hepatite C/metabolismo , Ferro/análise , Cirrose Hepática/metabolismo , Adulto , Cobre/sangue , Progressão da Doença , Feminino , Cabelo/química , Hepatite C/sangue , Humanos , Ferro/sangue , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Couro Cabeludo , Espectrofotometria Atômica , Fatores de Tempo
4.
J AOAC Int ; 97(6): 1662-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25632442

RESUMO

Extensive investigation has shown that smokeless tobacco (SLT) may cause inflammation of the oral cavity. In this study, the concentration of arsenic (As) was determined in SLT products (gutkha, mainpuri, and dry and moist snuff). Scalp hair samples of males aged 20-30 years who consumed different types of SLT products available in Pakistan were analyzed for As contents. Total As in different SLT products and in scalp hair was determined by electrothermal atomic absorption spectrometry after microwave-assisted extraction. The validity of the methodology was tested by simultaneously analyzing certified reference materials and spike recovery studies. The range of As concentrations in moist snuff, dry snuff, gutkha, and mainpuri were 0.574-1.53, 0.642-1.07, 0.246-0.622, and 0.419-0.874 µg/g, respectively. We estimated that a daily intake of 10 g of all SLT products could contribute 2.0-12.2% of the provisional maximum tolerable daily intake for As in adults. The As concentration in scalp hair of SLT consumers was higher than that of referents who had not consumed any type of tobacco products.


Assuntos
Arsênio/análise , Tabaco sem Fumaça/análise , Adulto , Cabelo/química , Humanos , Masculino , Paquistão , Couro Cabeludo/química , Espectrofotometria Atômica/métodos , Adulto Jovem
5.
Environ Toxicol Pharmacol ; 36(3): 858-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23981376

RESUMO

In present study the lead (Pb) levels has been assessed by analyzing the scalp hair and blood samples of mentally retarded/intellectual disabled (MR/ID) children of both genders, age ranged 3-8 years. For comparative purpose, healthy age matched children were also selected. The cloud point extraction of Pb from digested biological samples was carried out by complexed with ammonium pyrrolidinedithiocarbamate. The complexed analyte was subsequently isolated from the aqueous matrix in the micelles of a non-ionic surfactant (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Pb content was measured by flame atomic absorption spectrometer. Factors affecting the cloud point extraction were evaluated and optimized. The proposed procedure allowed the determination of lead in certified standard and real samples with detection limits of 0.834µgL(-) and enhancement factor 55. The results were compared with those of healthy children have same age, socioeconomic status and residential areas.


Assuntos
Deficiência Intelectual/sangue , Intoxicação do Sistema Nervoso por Chumbo na Infância/sangue , Chumbo/análise , Análise de Variância , Criança , Pré-Escolar , Contagem de Eritrócitos , Feminino , Cabelo/química , Humanos , Indicadores e Reagentes , Deficiência Intelectual/psicologia , Testes de Inteligência , Chumbo/sangue , Intoxicação do Sistema Nervoso por Chumbo na Infância/psicologia , Masculino , Micro-Ondas , Fatores de Risco , Espectrofotometria Atômica , Inquéritos e Questionários
6.
Environ Monit Assess ; 185(6): 5199-208, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23064896

RESUMO

The extent to which smokeless tobacco endangers human health is an ongoing subject of debate. In this study, concentrations of toxic metals, cadmium (Cd), lead (Pb), and nickel (Ni), were measured in different snuff products (dry brown and black and moist green and brown), available and consumed in Pakistan. Concentrations of Cd, Pb, and Ni were determined in 23 samples of various brands of snuff by electrothermal atomic absorption spectrometry, after microwave-assisted acid digestion. The reliability of methodology was assured by analyzing certified reference material. The resulted data of toxic metals in different snuff products are comparable to the existing information with limited exceptions. It was estimated that 10 g intake of different types of snuff could contribute 14-68, 17-47, and 20-73 % of the provisional maximum tolerable daily intake for Cd, Ni, and Pb, respectively.


Assuntos
Metais/análise , Nicotiana/química , Produtos do Tabaco/análise , Cádmio/análise , Chumbo/análise , Níquel/análise , Paquistão , Tabaco sem Fumaça/análise
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