Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Microsc Res Tech ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39051772

RESUMO

In the developing field of nanotechnology, ZnO (zinc oxide) based semiconductor samples have emerged as the foremost choice due to their immense potential for advancing the development of cutting-edge nanodevices. Due to its excellent chemical stability, low cost, and non-toxicity to biological systems, it is also utilized in various investigations. In this study, the successive ionic layer adsorption and reaction (SILAR) method was used to generate FTO (fluorine-doped tin oxide)/ZnO, and tin (Sn)-copper (Cu)-doped ZnO thin films at varying concentrations on FTO substrates. After being stacked 40 times in varying concentrations on the FTO substrate, FTO/ZnO thin films and Sn-Cu-doped thin films were annealed at 300°C. Using Scanning Electron Microscopy (SEM) Energy Dispersive Spectroscopy-(EDS), the agar diffusion test, and the viability cell counting method, the minimum inhibitory concentration, structural properties, surface morphology, antibacterial properties, bacterial adhesion, and survival organism count of FTO/ZnO thin films and Sn-Cu-doped thin films were investigated. Both doped and FTO/ZnO films with varying Sn-Cu concentrations expanded harmonically on the FTO substrate, according to the SEM-EDS investigation. The doping concentration affected their morphological properties, causing changes depending on the doping level. Antibacterial activity was observed in the powder metals, but no antibacterial activity was found in the thin film form. The highest adhesion rate of bacterial organisms on the produced samples was observed when the FTO/ZnO/Sn-Cu doping rate was 1%. In addition, the lowest adhesion rate was observed when the FTO/ZnO/Sn-Cu additive ratio was 3%. RESEARCH HIGHLIGHTS: ZnO based semiconductors highlight significant potential in advancing nanodevice technology due to their chemical stability, cost-effectiveness, and biocompatibility. Employing the SILAR method, the study innovatively fabricates FTO/ZnO and Sn-Cu-doped ZnO thin films on FTO substrates, exploring a novel approach in semiconductor manufacturing. Post annealing at 300°C, the research examines the structural and surface morphological changes in the films, contributing to the understanding of semiconductor behavior under varying conditions. The study delves into the antibacterial properties of ZnO thin films, offering insights into the potential biomedical applications of these materials. SEM-EDS analysis reveals that doping concentrations crucially influence the morphological properties of ZnO thin films, shedding light on the optimization of semiconductor performance. Findings indicate a specific doping rate (1% Sn-Cu) enhances bacterial adhesion, while a 3% additive ratio minimizes it, suggesting implications for biomedical device engineering and antibacterial surface design.

2.
Environ Sci Pollut Res Int ; 28(13): 16458-16469, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33387311

RESUMO

The main objective of this work was to investigate the root cause(s) of the various diseases in the local population, living in the proximity of chromium mining area. The analytical work was done on the samples of drinking water, soil and human blood, collected from the study area. The chosen study area is known as Muslim Bagh, located in the Balochistan province of Pakistan. The area is well-known for chromite hub. The hub comprises about 325 open-cast and underground mines, 100 dumping sites and 11 chrome beneficiation plants. The presented investigation is the first report of its nature on the contamination of heavy metals (HM) in the samples of drinking water and soil of the study area. The traces of different HM were also found in the random blood samples of human population in the study area. The amount of Co, Ni, Pb, As and Cr in the soil samples of the study area was obtained in the range of 990 × 103-1837 × 103, 1 × 103-11 × 103, 1 × 103-15 × 103, 84 × 103-187 × 103 and 6.9 × 106-19.5 × 106 (µg/kg ppb), respectively, whereas the samples of drinking water of the area found were 199-997 Co, 40-1370 Ni, 30-740 Pb, 47-890 As and 1990-13,530 (µg/kg ppb) of Cr. The obtained data of the physiochemical properties and the amount of HM show that the available drinking water sources are unfit for human consumption, mainly because of the chromium amount. Questionnaire analysis of the local population was also revealed that there was no awareness or feeling about metal poisoning in the targeted people and had no idea about the metal contaminations and diseases caused by this. Human health risk assessment for both carcinogenic and non-carcinogens concludes that the children and adults of the area are at high risk of several diseases and disorders.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , China , Cromo , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Paquistão , Medição de Risco , Solo , Poluentes do Solo/análise
3.
Environ Sci Pollut Res Int ; 28(2): 2355-2368, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32880840

RESUMO

Contamination of arsenic and fluoride in drinking water reservoirs is a serious health issue in the Sibi district, Balochistan, Pakistan. The contamination has already been affecting a large population of the district. Dental fluorosis and dermatitis are the most common reported illnesses in the area. This study focused on the evaluation of the root causes and pathway by which it reached to the body. Questioner analysis, simple examination, and pictorial representation were used to study the prevalence of diseases caused by As and F. People of the Sibi district were found to consume both surface and groundwater, which were highly contaminated with arsenic and fluoride. The saturation index, ranging from 1 to 7, showed high enrichment of contaminants in both types of water. Geochemical calculations and the sodium absorption ratio were evaluated. High values of the saturation index of different salts showed high saturation of salts in water. The principal component analysis grouped the data into three clusters, showing that the surface water has no resemblance with the control water. High degree of contamination was observed for most of the samples, whereas, some samples of ground water were closed to the control group; a group of samples within WHO limits. The correlation studies and other calculations also revealed that the F and As reached lethal limits in the drinking water and thus caused severe health damage to the local area population. The diseases found in the area are fluorosis, keratosis, dermatitis, and melanosis.


Assuntos
Arsênio , Água Potável , Fluorose Dentária , Água Subterrânea , Poluentes Químicos da Água , Arsênio/análise , Água Potável/análise , Monitoramento Ambiental , Fluoretos/análise , Fluorose Dentária/epidemiologia , Fluorose Dentária/etiologia , Humanos , Paquistão , Poluentes Químicos da Água/análise
4.
Biol Trace Elem Res ; 172(2): 419-423, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26743862

RESUMO

The purpose of this study is to examine the effect of the caffeic acid phenethyl ester (CAPE) fortification applied to the rats, which were made to exercise, on the liver elements. The study was conducted on 32 Sprague-Dawley male rats. The experimental animals were divided into 4 groups in equal numbers. Group 1 is the group which was applied 10 µmol/kg/day CAPE as intraperitoneal (IP) for 4 weeks, and they were not made to exercise at the end of the application. Group 2 is the group which was applied 10 µmol/kg/day CAPE as IP for 4 weeks, and they were made to exercise at the end of the 4th week. Group 3 is the general control group. Group 4 is the swimming control group. A 10 mmol/kg CAPE application dissolved in ethyl alcohol of 10 % was applied to the CAPE group. Sodium (Na), zinc (Zn), calcium (Ca), iron (Fe), chrome (Cr), magnesium (Mg), potassium (K), copper (Cu) and cadmium (Cd) levels were identified in the liver samples at the end of the application. The results of the study suggest that exercise and CAPE fortification in rats cause changes in the Na, Zn, Ca, Fe and Cr parameters in liver tissues, and it does not affect Cd, Cu, Mg and K element distribution. It is thought that CAPE fortification would be helpful for preserving those parameters whose levels are known to be changing with exercise.


Assuntos
Ácidos Cafeicos/farmacologia , Fígado/efeitos dos fármacos , Álcool Feniletílico/análogos & derivados , Condicionamento Físico Animal , Animais , Cádmio/análise , Ácidos Cafeicos/administração & dosagem , Cálcio/análise , Cromo/análise , Cobre/análise , Injeções Intraperitoneais , Ferro/análise , Fígado/química , Fígado/metabolismo , Magnésio/análise , Masculino , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/farmacologia , Potássio/análise , Ratos , Ratos Sprague-Dawley , Sódio/análise , Distribuição Tecidual , Zinco/análise
5.
J Hazard Mater ; 195: 332-9, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21889841

RESUMO

New nano hybrid material (ZrO(2)/B(2)O(3)) was synthesized and applied as a sorbent for the separation and/or preconcentration of Co(II), Cu(II) and Cd(II) in water and tea leaves prior to their determination by flame atomic absorption spectrometry. Synthesized nano material was characterized by scanning electron microscope, transmission electron microscope and X-ray diffraction. The optimum conditions for the quantitative recovery of the analytes, including pH, eluent type and volume, flow rate of sample solution were examined. The effect of interfering ions was also investigated. Under the optimum conditions, adsorption isotherms and adsorption capacities have been examined. The recoveries of Co(II), Cu(II) and Cd(II) were 96 ± 3%, 95 ± 3%, 98 ± 4% at 95% confidence level, respectively. The analytical detection limits for Co(II), Cu(II), and Cd(II) were 3.8, 3.3, and 3.1 µg L(-1), respectively. The reusability and adsorption capacities (32.2 mg g(-1) for Co, 46.5 mg g(-1) for Cu and 109.9 mg g(-1) for Cd) of the sorbent were found as satisfactory. The accuracy of the method was confirmed by analyzing certified reference material (GBW-07605 Tea leaves) and spiked real samples. The method was applied for the determination of analytes in tap water and tea leaves.


Assuntos
Cádmio/isolamento & purificação , Quelantes/química , Cobre/isolamento & purificação , Nanoestruturas , Extração em Fase Sólida/métodos , Adsorção , Compostos de Boro/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Termodinâmica , Difração de Raios X , Zircônio/química
6.
Acta Chim Slov ; 57(2): 491-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24061750

RESUMO

A new indirect method for the determination of iodide and thiosulfate ions in table salt and milk by flame atomic absorption spectrometry was described. This method is based on the reduction of chromium (VI) to chromium(III) with the reducing action of iodide and/or thiosulfate, separation of unreacted Cr(VI) as its 1,5-diphenilcarbazide complex on a column filled with Amberlite XAD-16, elution of the complex by 10 mL of 0.05 mol L-1 H2SO4 in methanol and determination by flame atomic absorption spectrometry. Amount of the analytes were calculated from the amount of Cr(VI) reacted with the analytes. The optimum conditions for the determination of iodide and thiosulfate ions, including pH and volume of sample solution were examined. The effect of interfering species on the recovery of the iodide and thiosulfate ions was also investigated. The precision of the proposed method is good as it provides relative standard deviation value of 3.5% for thiosulfate and 4.5% for iodide during five replicate determinations of 10 µg mL-1 of thiosulfate and 15 µg mL-1 of iodide, respectively. The accuracy of the procedure was tested by analyzing spiked real samples and certified reference sample (BCR 150 Milk powder). The procedure described was successfully applied for the determination of iodide in table salt and milk and, thiosulfate in table salt. Iodide and thiosulfate ions have been determined in real samples with relative error below 15%.

7.
J Hazard Mater ; 166(1): 455-61, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19135793

RESUMO

A new solid phase extractor, nano-scale diboron trioxide/titanium dioxide composite material, was synthesized and used for separation and/or preconcentration of trace cadmium ion from various samples. The characterization of the synthesized material was performed by scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffractometer methods (XRD). The specific surface area of the material was also determined and found as 3.4m(2)/g. Analytical parameters including pH of sample solution, sample volume, flow rate of sample solution, volume and concentration of eluent for the column solid phase extraction (SPE) procedure were examined. The effect of common matrix ions on the recovery of the cadmium has also been investigated and found that they did not interfere on cadmium preconcentration. Under the optimum experimental conditions, preconcentration factor and analytical detection limit were determined as 50 and 1.44 microg/L, respectively. The reusability (stabile up to 100 run) and adsorption capacity (49 mg/g) of the sorbent were excellent. The accuracy of the method was confirmed by analyzing certified reference materials (Tea leaves GBW-07605). The results demonstrated good agreement with the certified values (relative error <10%). The precision of the method was also satisfactory. The recovery of cadmium under the optimum conditions was found to be 96+/-3% at 95% confidence level. The method was applied for the determination of cadmium in tap water and tea leaves.


Assuntos
Cádmio/isolamento & purificação , Poluentes Ambientais/isolamento & purificação , Nanocompostos/química , Extração em Fase Sólida/métodos , Adsorção , Compostos de Boro/química , Cádmio/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Padrões de Referência , Propriedades de Superfície , Chá/química , Titânio/química , Poluentes da Água/análise , Poluentes da Água/isolamento & purificação
8.
Talanta ; 69(4): 835-40, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970645

RESUMO

This work assesses the potential of a new adsorptive material, Amberlyst 36, for the separation and preconcentration of trace manganese(II) from various media. It is based on the sorption of manganese(II) ions onto a column filled with Amberlyst 36 cation exchange resin, followed by the elution with 5mL of 3mol/L nitric acid and determination by flame atomic absorption spectrometry (FAAS) without interference of the matrix. Different factors including pH of sample solution, sample volume, amount of resin, flow rate of sample solution, volume and concentration of eluent, and matrix effects for preconcentration were investigated. Good relative standard deviation (3%) and high recovery (>95%) at 100mug/L and high enrichment factor (200) and low analytical detection limit (0.245mug/L) were obtained. The adsorption equilibrium was described well by the Langmuir isotherm model with maximum adsorption capacity of 88mg/g of manganese on the resin. The method was applied for the manganese determination by FAAS in tap water, commercial natural drinking water, commercial treated drinking water and commercial tea bag sample. The accuracy of the method is confirmed by analyzing the certified reference material (tea leaves GBW 07605). The results demonstrated good agreement with the certified values.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...