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1.
Food Chem Toxicol ; 169: 113398, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36096291

RESUMO

It is necessary to determine whether synthetic dyes are present in food since their excessive use has detrimental effects on human health. For the simultaneous assessment of tartrazine and Patent Blue V, a novel electrochemical sensing platform was developed. As a result, two artificial azo colorants (Tartrazine and Patent Blue V) with toxic azo groups (-NN-) and other carcinogenic aromatic ring structures were examined. With a low limit of detection of 0.06 µM, a broad linear concentration range 0.09µM to 950µM, and a respectable recovery, scanning electron microscopy (SEM) was able to reveal the excellent sensing performance of the suggested electrode for patent blue V. The electrochemical performance of an electrode can be characterized using cyclic and differential pulse voltammetry, and electrochemical impedance spectroscopy. Moreover, the classification model was created by applying binary classification assessment using enhanced artificial intelligence comprises of support vector machine (SVM) and Genetic Algorithm (GA), respectively, a support vector machine and a genetic algorithm, which was then validated using the 50 dyes test set. The best binary logistic regression model has an accuracy of 83.2% and 81.1%, respectively, while the best SVM model has an accuracy of 90.3% for the training group of samples and 81.1% for the test group (RMSE = 0.644, R2 = 0.873, C = 205.41, and = 5.992). According to the findings, Cu-BTC MOF (copper (II)-benzene-1,3,5-tricarboxylate) has a crystal structure and is tightly packed with hierarchically porous nanomaterials, with each particle's edge measuring between 20 and 37 nm. The suggested electrochemical sensor's analytical performance is suitable for foods like jellies, condiments, soft drinks and candies.


Assuntos
Inteligência Artificial , Compostos Azo , Técnicas Eletroquímicas , Corantes de Alimentos , Contaminação de Alimentos , Corantes de Rosanilina , Tartrazina , Humanos , Compostos Azo/análise , Compostos Azo/isolamento & purificação , Técnicas Eletroquímicas/métodos , Eletrodos , Corantes de Alimentos/análise , Corantes de Alimentos/isolamento & purificação , Contaminação de Alimentos/prevenção & controle , Corantes de Rosanilina/análise , Corantes de Rosanilina/isolamento & purificação
2.
Food Chem Toxicol ; 154: 112312, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34102214

RESUMO

Malachite green (MG) is extensively applied in aquaculture worldwide as a therapeutic agent. MG and its primary metabolite leucomalachite green (LMG) are commonly detected in aquaculture products. MG can cause serious health concerns (in vivo carcinogenic/genotoxic). The extensive water solubility of MG leads to water pollution and hence it is mandatory to remove MG from water. The current study explores adsorptive removal of MG from water using highly water stable Zeolitic Imidazolate framework/graphene oxide composites (ZIF-67@GO). Adsorption performance of newly synthesized composites is justified for MG removal with excellent results of pseudo second order (R2 = 0.99955) which is well-fitted in this case. ZIF-67@GO data of adsorption isotherm for MG is observed using Freundlich Model (R2 = 0.99999) and with adsorption capacity value observed (134.79 mg/g) with removal efficiency of 99.18%, indicates π-staking and electrostatic association between ZIF-67@GO and MG molecules. Synthesized material has retained reusability while removal efficiency reduced only by 6% after many cycles. Furthermore, factors effecting absorption like contact time, pH, adsorbent dose and quantity and temperature are also determined.


Assuntos
Grafite/química , Imidazóis/química , Estruturas Metalorgânicas/química , Corantes de Rosanilina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Temperatura , Termodinâmica
3.
Artigo em Inglês | MEDLINE | ID: mdl-30938571

RESUMO

In this study, iron oxide nanoparticles (IO-NPs) with a mean diameter of 102.85 nm were firstly synthesized via a facile green route using Ulva spp. aqueous extract as a bioreductant agent. Then, IO-NPs were loaded into carbonated hydroxyapatite (c-Hap) and the final product was named as the iron oxide nanoparticles loaded carbonated hydroxyapatite (IO-NPs-Lc-Hap). Subsequently, IO-NPs-Lc-Hap was characterized by FT-IR, SEM, XRD and EDX analysis methods. MG colour removal efficiencies of Ulva spp., Hap, IO-NPs and IO-NPs-Lc-Hap materials were also evaluated by adsorption and/or Fenton-like reaction methods. IO-NPs-Lc-Hap with the highest decolourization capacity was chosen as a heterogeneous Fenton-like catalyst for Malachite Green (MG). For Fenton-like decolourization of MG, the optimum H2O2 concentration, initial dye concentration and catalyst concentration were determined to be 30 mM, 100 mg/L and 1.0 g/L, respectively. At these optimum conditions, 100% decolourization efficiency and 33.3% COD removal were obtained. On the other hand, 94% decolourization efficiency and 42% COD removal were achieved for the real textile wastewater at the obtained optimum conditions. The experimental decolourization reaction rate for MG was determined as -rd = 0.0779 [(mg dye0.3) (g cat-0.3) (min-1)] × qt0.7. Also, the catalyst had high decolourization efficiencies at the end of six sequence usages.


Assuntos
Corantes/isolamento & purificação , Durapatita/farmacologia , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Nanopartículas/química , Corantes de Rosanilina/isolamento & purificação , Adsorção , Carbonatos/química , Catálise , Corantes/farmacocinética , Durapatita/química , Compostos Férricos/síntese química , Compostos Férricos/farmacocinética , Corantes de Rosanilina/farmacocinética , Espectroscopia de Infravermelho com Transformada de Fourier , Ulva/química , Ulva/metabolismo , Águas Residuárias/química , Purificação da Água/métodos
4.
J AOAC Int ; 101(5): 1429-1436, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29724261

RESUMO

There is great interest in the search for multifunctional waste-based materials that may be applied as environmentally friendly adsorbents. Iron-rich sludge from ground drinking-water treatment plants may be considered a potential adsorbent for various water contaminants. This material is generated during ground water purification because of the excess of metal ions in water (Fe, Mn). In practice, this sludge is frequently disposed of as waste material and, so far, is not commonly applied as the adsorption base. Our research aims to explore the adsorption potential of iron sludge for selected synthetic dyes, including malachite green, ponceau 4R, and brilliant blue FCF. Experimental data were performed using iron sludge collected from the Groundwater Treatment Plant in Koszalin, Poland, and comparing it with adsorption properties of commercial activated carbons (Norit SA Super and Norit CA 1). The kinetics, adsorption isotherms, and temperature influence on the removal of target dyes were investigated and discussed. Preliminary experimental data have revealed that iron sludge can be considered an adsorbent for the removal of cationic dyes.


Assuntos
Corantes/isolamento & purificação , Ferro/química , Esgotos/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Compostos Azo/isolamento & purificação , Benzenossulfonatos/isolamento & purificação , Cinética , Naftalenossulfonatos/isolamento & purificação , Corantes de Rosanilina/isolamento & purificação
5.
Biotech Histochem ; 89(2): 121-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23977956

RESUMO

A simple low pressure liquid chromatographic method is reported that can separate the basic fuchsine homologues, rosaniline, magenta II and new fuchsine from an impure commercial dye. The chromatographic purity of the separated dyes is > 90%. All homologues were obtained in multi-milligram amounts per chromatographic run; precise yields depend on the composition of the starting material and potentially may be greater. This is a useful preparative procedure for generating chromatographically pure samples of basic fuchsine homologues, especially those that cannot be obtained in pure form by direct synthesis.


Assuntos
Cromatografia Líquida de Alta Pressão , Corantes de Rosanilina/isolamento & purificação , Estrutura Molecular , Corantes de Rosanilina/química
6.
J Hazard Mater ; 192(1): 62-70, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21616589

RESUMO

We report a method for the removal of malachite green (MG) by adsorption and precipitation using nano-sized aminopropyl functionalized magnesium phyllosilicate (AMP) clay. MG, which is used in aquaculture and fisheries, is a carcinogenic and mutagenic compound. In response to these health risks, many efforts have been focused on adsorption of MG onto various adsorbents, which is a versatile and widely used technique for removing MG from water. Herein, we describe the adsorption and precipitation of MG using AMP clay, as well as the alkaline fading phenomenon of MG. In this study, prepared AMP clay and the precipitate product after the reaction of MG-AMP clay mixture were characterized. In addition, adsorption isotherms and kinetics, as well as thermodynamic studies are presented. Based on the results, we suggest a macro- and microscopic removal mechanism for the adsorption and precipitation of MG using AMP clay. An AMP clay dosage of 0.1 mg mL(-1) exhibited a maximum removal capacity of 334.80 mg g(-1) and 81.72% MG removal efficiency. With further increases of the AMP clay dosage, removal capacity by AMP clay gradually decreased; at dosage above 0.2 mg mL(-1) of AMP clay, the removal efficiency reached 100%.


Assuntos
Magnésio/química , Corantes de Rosanilina/isolamento & purificação , Silicatos/química , Adsorção , Silicatos de Alumínio , Argila , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Padrões de Referência , Termodinâmica , Difração de Raios X
7.
Appl Biochem Biotechnol ; 160(5): 1394-406, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19277479

RESUMO

In this study, poly(amic acid)-modified biomass was prepared to improve the adsorption capacities for two cationic dyes, methylene blue and basic magenta. X-ray photoelectron spectroscopy and potentiometric titration demonstrated that a large number of imide, amine, and carboxyl groups were introduced on the biomass surface, and the concentrations of these functional groups were calculated to be 0.27, 1.08, and 1.08 mmol g(-1) by using the first derivative method. According to the Langmuir equation, the maximum uptake capacities (q(m)) for methylene blue and basic magenta were 680.3 and 353.4 mg g(-1), respectively, which were 13- and sevenfold than that obtained on the unmodified biomass. Adsorption kinetics study showed that the completion of the adsorption process needed only 40 min, which is faster than the common sorbent such as activated carbon and resin. Experimental results showed that pH and ionic strength had little effect on the capacity of the modified biomass, indicating that the modified biomass had good potential for practical use.


Assuntos
Derivados de Benzeno/metabolismo , Biomassa , Azul de Metileno/isolamento & purificação , Polímeros/metabolismo , Corantes de Rosanilina/isolamento & purificação , Saccharomyces cerevisiae/metabolismo , Adsorção , Derivados de Benzeno/química , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Concentração Osmolar , Espectroscopia Fotoeletrônica , Polímeros/química , Potenciometria , Corantes de Rosanilina/química , Saccharomyces cerevisiae/ultraestrutura , Temperatura
8.
Chemosphere ; 77(8): 1090-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19786292

RESUMO

Natural organic coagulants (NOCs) such as chitosan and Moringa oleifera seeds have been extensively characterized for potential application in water treatment as an alternative to metal-based coagulants. However, the action of both chitosan and M. oleifera seeds is mainly restricted to anionic organic pollutants because of their cationic functional groups affording poor cationic pollutant coagulation by electrostatic repulsion. In this study, we employed ethanolic grape seed extract (GSE) and grape seed-derived polyphenols such as tannic acid and catechin in an effort to find novel NOCs showing stable anionic forms for removal of cationic organic pollutants. The target substances tested were malachite green (MG) and crystal violet (CV), both mutagenic cationic dyes. Polyphenol treatment induced fast decolorization followed by gradual floc formation concomitant with red or blue shifts in maximum absorbance wavelengths of the cationic dyes. Liquid chromatography analysis of flocs formed by polyphenols directly showed that initial supramolecular complexes attributed mainly to electrostatic attraction between polyphenol hydroxyphenyl groups and cationic dyes further progressed into stronger aggregates, leading to precipitation of dye-polyphenol complexes. Consistent with the results obtained using catechin and tannic acid, use of GSE also resulted in effective decolorization and coagulation of soluble MG and CV in aqueous solutions. Screening of several organic GSE components for NOC activity strongly suggested that natural polyphenols are the main organic ingredients causing MG and CV removal via gradual floc formation. The treatment by natural polyphenols and GSE decreased toxicity of MG- or CV-contaminated water.


Assuntos
Corantes/química , Corantes/isolamento & purificação , Flavonoides/química , Extrato de Sementes de Uva/química , Fenóis/química , Sementes/química , Vitis/química , Catequina/química , Precipitação Química , Corantes/toxicidade , Etanol/química , Violeta Genciana/química , Violeta Genciana/isolamento & purificação , Violeta Genciana/toxicidade , Polifenóis , Corantes de Rosanilina/química , Corantes de Rosanilina/isolamento & purificação , Corantes de Rosanilina/toxicidade , Taninos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/toxicidade
10.
Talanta ; 77(4): 1328-31, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19084644

RESUMO

This study presents a novel separation, preconcentration and determination of basic fuchsin (BF) in an aqueous solution by sodium dodecyl sulfate (SDS)-bounded iron oxide nanoparticles (S-IONPs). It is shown that the novel magnetic nano-adsorbent is quite efficient for the adsorption and desorption of BF at 25 degrees C. Different parameters such as pH, temperature, ionic strength and composition of desorbent solvent were optimized. The effect of some co-existing ions on the determination was investigated. The nanoparticles were analyzed by transmission electron microscopy (TEM) and the sizes of S-IONPs were in the range of 20-100 nm. The method showed good linearity for the determination of BF in the range of 10-300 ng mL(-1) with a regression coefficient of 0.9989. The limit of detection (LOD) (signal-to-noise ratio of 3:1) was 0.0073 microg L(-1) and the relative standard deviation (RSD) for 0.03 microg mL(-1) and 0.2 microg mL(-1) of BF were 4.53% and 4.73%, respectively. The BF was determined successfully in spiked samples of Karoon River water.


Assuntos
Compostos Férricos/química , Nanopartículas Metálicas/química , Corantes de Rosanilina/análise , Corantes de Rosanilina/isolamento & purificação , Espectrofotometria/métodos , Adsorção , Compostos Férricos/análise , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Modelos Químicos , Nanopartículas , Nanotecnologia/métodos , Solventes/química , Temperatura , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
11.
J Hazard Mater ; 162(1): 378-85, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18603364

RESUMO

The aim of this paper is to study the adsorption of the acid dye Supranol Yellow 4 GL (S.Y. 4 GL) from aqueous solution on an inorgano-organo clay. Bentonite is naturally occurring clay with good exchanging ability. By exchanging its interlamellar cations with cetyltrimethylammonium bromide (CTAB) and hydroxyaluminic or chromium polycations, the properties of natural bentonite can be greatly improved. Batch adsorption tests of Supranol Yellow 4 GL were carried out at 20 degrees C and constant pH 6.5. To investigate the adsorption mechanisms, the simplified kinetic models, such as pseudo-first-order, pseudo-second-order, Elovich equation and intraparticle diffusion are tested. The results show that adsorption follows second-order rate kinetic. The correlation coefficients obtained for second-order kinetics model are greater than 0.998 indicating a better fitting of this equation. The experimental data are analysed by Langmuir, Freundlich and Elovich isotherms. The equilibrium adsorption capacity of anionic dye is determined from the Langmuir equation and found to be 142, 85 and 128, 20mg/g (standard deviation; Deltaq (%)=3.52 and 18.51) for CTAB-Cr-B and CTAB-Al-B, respectively.


Assuntos
Alumínio/química , Bentonita/química , Cromo/química , Corantes de Rosanilina/química , Tensoativos/química , Adsorção , Algoritmos , Cetrimônio , Compostos de Cetrimônio , Difusão , Cinética , Modelos Lineares , Corantes de Rosanilina/isolamento & purificação , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Água , Difração de Raios X
12.
Artigo em Inglês | MEDLINE | ID: mdl-14533924

RESUMO

Thephotocatalytic degradation of two selected textile dye derivatives, eosine yellowish (1) and p-rosaniline (2) has been investigated in aqueous suspensions of titanium dioxide under a variety of conditions. The degradation was studied by monitoring the change in substrate concentration employing UV spectroscopic technique and decrease in Total Organic Carbon (TOC) content as a function of irradiation time under a variety of conditions. The degradation of the dye was studied under different conditions such as pH, catalyst concentration, substrate concentration, different types of TiO2 and in the presence of electron acceptor such as hydrogen peroxide (H2O2), potassium bromate (KBrO3), and ammonium persulphate (NH4)2S2O8) besides molecular oxygen. The degradation rates were found to be strongly influenced by all the above parameters. The photocatalyst Degussa P25 was found to be more efficient as compared with other photocatalyst in the case of p-rosaniline, whereas UV100 was found to be better for the degradation of eosine yellowish. The xanthene dye (1) was found to degrade faster as compared to the triphenylmethane dye (2). The degradation products were analyzed by GC/MS technique and plausible mechanism for the formation of products have been proposed.


Assuntos
Corantes/química , Amarelo de Eosina-(YS)/química , Amarelo de Eosina-(YS)/isolamento & purificação , Corantes Fluorescentes/química , Corantes Fluorescentes/isolamento & purificação , Corantes de Rosanilina/química , Corantes de Rosanilina/isolamento & purificação , Indústria Têxtil , Titânio/química , Purificação da Água/métodos , Catálise , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio/química , Oxidantes/química , Fotoquímica
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