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1.
J Chromatogr A ; 1307: 21-6, 2013 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-23932224

RESUMO

New ionic liquid-mediated molecularly imprinted polymers (IL-MIPs) were prepared by precipitation polymerization using 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM(+)PF6(-)) as the auxiliary solvent, α-chloro-DDT as the dummy template, and they were successfully applied as the sorbents of solid-phase extraction (SPE) for rapid screening of dicofol from cabbage, tomato, and carrot samples. The IL-MIPs were characterized by FTIR, FE-SEM, static adsorption and chromatographic evaluation, and the results revealed that the IL-MIPs had higher adsorption capacity and selectivity to dicofol in aqueous solution than that of ionic liquid-mediated non-imprinted polymers (IL-NIPs) and non-imprinted polymers (NIPs). Under the optimized conditions, the IL-MIPs-SPE-GC method offered good linearity (0.4-40.0ngg(-1), r(2)=0.9995) and the average recoveries of dicofol at three spiked levels were in a range of 84.6-104.1% (n=3) with RSD≤7.6%. The proposed method obviously improved the selectivity and purification effect, and eliminated the effect of template leakage on dicofol quantitative analysis.


Assuntos
Dicofol/análise , Líquidos Iônicos/química , Impressão Molecular/métodos , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Verduras/química , Acetonitrilos/química , Adsorção , Cromatografia Gasosa/métodos , Dicofol/química , Dicofol/isolamento & purificação , Concentração de Íons de Hidrogênio , Imidazóis/química , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Polimerização , Reprodutibilidade dos Testes
2.
Environ Technol ; 33(4-6): 695-701, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629645

RESUMO

Organic micropollutants are often found in domestic and industrial effluents. Thus, it is important to learn their fate, the metabolites generated and their sorption during biological treatment processes. This work investigated the biodegradation of 14C-dicofol organochloride during wastewater aerobic treatment and sludge anaerobic biodigestion. The performance of these processes was evaluated by physical-chemical parameters. Radioactivity levels were monitored in both treatments, and residues of dicofol (DCF) and dichlorobenzophenone (DBP) were quantified by HPLC/UV. The efficiency of the aerobic and anaerobic processes was slightly reduced in the presence of DCF and DBP. After aerobic treatment, only 0.1% of DCF was mineralized, and 57% of radioactivity remained sorbed on biological sludge as DBP. After 18 days of anaerobiosis, only 3% of DCF and 5% of DBP were detected in the sludge. However, 70% of radioactivity remained in the sludge, probably as other metabolites. Dicofol was biodegraded in the investigated process, but not mineralized.


Assuntos
Bactérias Aeróbias/metabolismo , Bactérias Anaeróbias/metabolismo , Dicofol/metabolismo , Herbicidas/metabolismo , Resíduos Industriais/prevenção & controle , Esgotos/microbiologia , Purificação da Água/métodos , Biodegradação Ambiental , Radioisótopos de Carbono/isolamento & purificação , Radioisótopos de Carbono/metabolismo , Dicofol/isolamento & purificação , Herbicidas/isolamento & purificação , Marcação por Isótopo , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
3.
Talanta ; 85(4): 2100-5, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21872064

RESUMO

The novel molecularly imprinted microsphere (MIM) that could be applied as special sorbent was synthesized by aqueous suspension polymerization using 1,1-bis(4-chlorophenyl)-1,2,2,2-tetrachloroethane (α-chloro-DDT) as the dummy template. The obtained MIM exhibited good recognition and selectivity to dicofol and it was successfully applied as selective sorbent of solid-phase extraction for the determination of dicofol from aquatic products. At the optimum conditions of the molecularly imprinted solid-phase extraction (MISPE) coupled with GC-ECD, good linearity for dicofol was achieved in a range of 0.4-100 ng g(-1) (r(2)=0.9995) and the recoveries at three spiked levels were ranged from 85.8% to 101.2% for aquatic products with the relative standard deviation (RSD) less than 5.6%. The presented MISPE-GC-ECD method exhibited the advantages of simplicity, selectivity and sensitivity, and could be potentially applied to the determination of dicofol in complicated aquatic products.


Assuntos
Organismos Aquáticos/química , Cromatografia Gasosa/métodos , Dicofol/análise , Dicofol/isolamento & purificação , Elétrons , Impressão Molecular/métodos , Extração em Fase Sólida/métodos , Animais , DDT/análogos & derivados , DDT/química , Decápodes/química , Poluentes Ambientais/análise , Poluentes Ambientais/isolamento & purificação , Peixes , Microesferas
4.
Braz. j. microbiol ; 39(2): 311-313, Apr.-June 2008. graf
Artigo em Inglês | LILACS | ID: lil-487710

RESUMO

The fate of organochlorine 14C-dicofol in activated sludge process was investigated. Results showed that the major part of radioactivity remained adsorbed on biological sludge. Consequently, its final disposal deserves special attention. The small amounts of dicofol, biotransformed or not, which remained in the treated effluent could contaminate receiving bodies.


A dinâmica do organoclorado 14C-dicofol no processo de lodos ativados foi investigada. Os resultados mostraram que a maior parte da radioatividade ficou adsorvida no lodo biológico. Consequentemente, o seu descarte final merece atenção especial. Pequenas quantidades de dicofol, biotransformadas ou não, permanecem no efluente tratado podendo contaminar os corpos receptores.


Assuntos
Lodos Ativados , Águas Residuárias , Esgotos Domésticos , Dicofol/análise , Dicofol/isolamento & purificação , Microbiologia Ambiental , Técnicas In Vitro , Inseticidas Organoclorados , Biotransformação , Métodos , Radioatividade
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