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1.
J Cancer Res Ther ; 11(4): 1006-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26881570

RESUMO

Complementary and alternative medicine (CAM) use among cancer patients is widely prevalent and often underreported. Advanced stage of disease is significantly associated with CAM use. The concurrent use of alternative medicines and chemotherapy drugs has the potential to lead to toxicities as well as altered therapeutic activity due to unknown interactions. We report a case of early breast cancer who presented to us with non-oliguric acute renal failure related concurrent use of Ayurvedic medicines and adjuvant anthracycline based.


Assuntos
Injúria Renal Aguda/etiologia , Neoplasias da Mama/terapia , Terapias Complementares/efeitos adversos , Adulto , Feminino , Humanos , Prognóstico
2.
Anal Chim Acta ; 851: 87-94, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25440669

RESUMO

A visual strip has been developed for sensing iron in different aqueous samples like natural water and fruit juices. The sensor has been synthesized by UV-radiation induced graft polymerization of acrylamide monomer in microporous poly(propylene) base. For physical immobilization of iron selective reagent, the in situ polymerization of acrylamide has been carried out in the presence of 1,10-phenanthroline. The loaded strip on interaction with Fe(II) in aqueous solution turned into orange red color and the intensity of the color was found to be directly proportional to the amount of Fe(II) in the aqueous sample. The minimal sensor response with naked eye was found for 50ngmL(-1) of Fe in 15min of interaction. However, as low as 20ngmL(-1) Fe could be quantified using a spectrophotometer. The detection limit calculated using the 3s/S criteria, where 's' is the standard deviation of the absorbance of blank reagent loaded strip and 'S' is the slope of the linear calibration plot, was 1.0ngmL(-1). The strip was applied to measure Fe in a variety of samples such as ground water and fruit juices.


Assuntos
Técnicas de Química Analítica/instrumentação , Ferro/análise , Fitas Reagentes/química , Água/química , Resinas Acrílicas/química , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Polimerização , Polipropilenos/química , Controle de Qualidade
3.
J Hazard Mater ; 262: 265-73, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24036149

RESUMO

A flat sheet sorbent with poly(hydroxamic acid) groups anchored on the microporous structure of poly(propylene) membrane was developed and applied for the preconcentration and determination of heavy elements from natural waters. The designing of the sorbent involved UV-irradiation induced graft polymerization of acrylamide using N,N'-methylene-bis-acrylamide (MBA) as the crosslinker on the poly(propylene) base followed by chemical modification of the grafted membrane to generate crosslinked poly(hydroxamic acid) (PHA) groups in its pores. The synthesized PHA-membrane was found to preconcentrate U, V, Cu, Cr, Fe and Pb quantitatively (95%) from aqueous samples over a wide pH range of 4-9. The sorbed trace elements were quantified by direct analysis of the membrane using Energy Dispersive X-ray Fluorescence (EDXRF). To test the applicability of the developed sorbent to real samples, interference effect of common matrix elements like Na, K, Ca and Mg on the uptake of the analytes at sub µg mL(-1) level was studied. The PHA sorbent was found to be immune to interferences from Na, K and Mg up to 1000 µg mL(-1) and Ca up to 100 µg mL(-1) for an analyte concentration of 1 µg mL(-1). The method detection limit for EDXRF measurement was 6-30 ng using a 2 cm × 2 cm sorbent.


Assuntos
Água Subterrânea/química , Metais/análise , Poluentes Químicos da Água/análise , Calibragem , Membranas Artificiais , Microscopia Eletrônica de Varredura , Espectrometria por Raios X
4.
J Hazard Mater ; 260: 1023-31, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23892170

RESUMO

Water contamination by boron is a widespread environmental problem. The World Health Organization (WHO) recommends maximum boron concentration of 2.4 mg L(-1) for drinking water. The paper presents a simple method for preparation of functionalized sheet sorbent for selective extraction of boron from natural water. The pores of commercially available poly(propylene) membrane were functionalized by room temperature in situ crosslinking of poly(vinylbenzyl chloride) with a cyclic diamine piperazine. The precursor membranes were chemically modified with N-methyl D-glucamine which is selective for boron. Characterization of membrane was carried out using scanning electron microscopy (SEM) and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) techniques. The functionalized membrane has been characterized in terms of parameters that influence the sorption of boron from aqueous streams like pH, uptake capacity, contact time, effects of competing ions and reusability. The maximum boron sorption capacity determined experimentally was 28 mg g(-1). The studies showed that trace concentrations of boron were quantitatively removed from water at neutral pH. The developed fixed site polymer sorbent exhibited high sorption capacity and fast kinetics as compared to various sorbents reported in literature. It was successfully applied for the removal of boron from ground water and seawater samples in presence of high concentration of interfering ions.


Assuntos
Boro/análise , Meglumina/química , Polímeros/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Aminas/química , Ânions , Boro/química , Água Subterrânea , Concentração de Íons de Hidrogênio , Íons , Cinética , Teste de Materiais , Microscopia Eletrônica de Varredura , Modelos Químicos , Polipropilenos/química , Polivinil , Porosidade , Água do Mar , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
5.
J Chromatogr Sci ; 50(1): 81-3, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22291061

RESUMO

In the present study an ion chromatographic method based on matrix elimination has been developed for the determination of anionic impurities in high purity cesium iodide crystals. The presence of impurities has a detrimental effect on the characteristics of detectors based on cesium iodide crystals. In particular, oxygen-containing anions inhibit the resolving power of scintillators and decrease the optical absorption. The quantitative determination of anions (fluoride, chloride, bromide, nitrate, phosphate, and sulphate) simultaneously in the high-purity cesium iodide crystals has not been carried out before. The large concentration of iodide poses a challenge in the determination of anions (especially phosphate and sulphate); hence, matrix elimination is accomplished by adopting a sample pretreatment technique. The method is validated for linearity, accuracy, and precision. The limit of detection for different anions is in the range of 0.3-3 µg/g, and the relative standard deviation is in the range of 4-6% for the overall method.


Assuntos
Césio/química , Cromatografia por Troca Iônica/métodos , Iodetos/química , Ânions/análise , Césio/normas , Contaminação de Medicamentos , Iodetos/normas , Reagentes de Laboratório/química , Reagentes de Laboratório/normas , Limite de Detecção , Reprodutibilidade dos Testes
6.
J Hazard Mater ; 201-202: 193-201, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22178281

RESUMO

Fluoride related health hazards (fluorosis) are a major environmental problem in many regions of the world. It affects teeth; skeleton and its accumulation over a long period can lead to changes in the DNA structure. It is thus absolutely essential to bring down the fluoride levels to acceptable limits. Here, we present a new inorganic-organic hybrid polymer sorbent having tailored fixed-sites for fluoride sorption. The matrix supported poly (bis[2-(methacryloyloxy)-ethyl]phosphate) was prepared by photo-initiator induced graft-polymerization in fibrous and microporous (sheet) host poly(propylene) substrates. These substrates were conditioned for selective fluoride sorption by forming thorium complex with phosphate groups on bis[2-methacryloyloxy)-ethyl] phosphate (MEP). These tailored sorbents were studied for their selectivity towards fluoride in aqueous media having different chemical conditions. The fibrous sorbent was found to take up fluoride with a faster rate (15 min for ≈76% sorption) than the sheet sorbent. But, the fluoride loading capacity of sheet sorbent (4,320 mg kg(-1)), was higher than fibrous and any other sorbent reported in the literature so far. The sorbent developed in the present work was found to be reusable after desorption of fluoride using NaOH solution. It was tested for solid phase extraction of fluoride from natural water samples.


Assuntos
Fluoretos/isolamento & purificação , Metacrilatos/química , Organofosfatos/química , Compostos Organofosforados/química , Ácidos Polimetacrílicos/química , Polipropilenos/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Água Potável/normas , Microscopia Eletrônica de Varredura , Soluções , Propriedades de Superfície
7.
Int J Anal Chem ; 2011: 813061, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21785596

RESUMO

A simple, rapid and accurate method for the determination of monoethanolamine (MEA) in PHWR steam-water circuits has been developed. MEA is added in the feed water to provide protection against corrosion while hydrazine is added to scavenge dissolved oxygen. The quantitative determination of MEA in presence of hydrazine was accomplished using derivatization ion chromatography with conductometric detection in nonsuppressed mode. A Metrosep cation 1-2 analytical column and a Metrosep cartridge were used for cation separation. A mixture of 4 mM tartaric acid, 20% acetone and 0.05 mM HNO(3) was used as eluent. Acetone in the mobile phase leads to the formation of different derivatives with MEA and hydrazine. The interferences due Na(+) and NH(4) (+) were eliminated by adopting a simple pretreatment procedure employing OnGuard-H cartridge. The limit of detection limit of MEA was 0.1 µg mL(-1) and the relative standard deviation was 2% for the overall method. The recovery of MEA added was in the range 95%-102%. The method was applied to the determination of MEA in steam generator water samples.

8.
J AOAC Int ; 92(1): 241-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19382582

RESUMO

The interaction of macrocyclic compounds like crown ethers and UO2(2+) has been studied by electrochemical methods. A modified carbon paste electrode incorporating benzo-15-crown-5 (B15C5) was used to evaluate the electron transfer reaction of UO2(2+) by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Electrochemical impedance studies showed that charge transfer resistance was less for the B15C5-modified electrode than for the plain carbon paste electrode (PCPE). On the basis of these observations, a UO2(2+)-sensitive crown ether chemically modified electrode (CME) for trace analysis was fabricated and investigated in aqueous solutions. It was found that a 5% B15C5-CME for UO2(2+) showed a better voltammetric response than did the PCPE. UO2(2+) could be quantified at sub-microg/mL levels by differential pulse voltammetry with a detection limit of 0.03 microg/mL. By differential pulse adsorptive stripping voltammetry, UO2(2+) could be quantified in the working range of 0.002-0.2 microg/mL, with a detection limit of 1.1 microg/L. Simultaneous determination of UO2(2+), Pb(2+), and Cd(2+) was possible. The method was successfully applied to the determination of UO2(2+) in synthetic, as well as real, samples; the results were found to be comparable to those obtained by inductively coupled plasma-atomic emission spectroscopy.


Assuntos
Eletroquímica/métodos , Íons/análise , Oligoelementos/análise , Urânio/análise , Carbono , Éteres de Coroa , Eletroquímica/instrumentação , Eletrodos , Desenho de Equipamento , Nióbio/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Chromatogr A ; 1046(1-2): 155-8, 2004 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-15387184

RESUMO

A simple, rapid and accurate method for the determination of chloride in magnesium metal has been developed. The quantitative determination of chloride was accomplished by anion exchange chromatography with conductometric determination. A Metrosep Anion Dual 2 analytical column connected in series with a Metrosep RP guard column was used for chloride separation. A solution containing a mixture of 1.3 mM Na2CO3 and 2 mM NaHCO3 was used as eluent. The method requires a sample dissolution using nitric acid. The limit of detection for the determination of chloride is 50 mg kg(-1) and the relative standard deviation was 5% for the overall method. The recovery of chloride added was 99-102%. No interference was observed from either the closely eluting "system peak" or the nitrate peak in the determination of chloride.


Assuntos
Cloretos/análise , Cromatografia Líquida/métodos , Magnésio/química , Sensibilidade e Especificidade
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