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1.
Toxins (Basel) ; 14(10)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36287972

RESUMO

Zearalenone (ZEN), also known as the F-2 toxin, is a common contaminant in cereal crops and livestock products. This experiment aimed to reveal the changes in the proteomics of ZEN-induced intestinal damage in weaned piglets by tandem mass spectrometry tags. Sixteen weaned piglets either received a basal diet or a basal diet supplemented with 3.0 mg/kg ZEN in a 32 d study. The results showed that the serum levels of ZEN, α-zearalenol, and ß-zearalenol were increased in weaned piglets exposed to ZEN (p < 0.05). Zearalenone exposure reduced apparent nutrient digestibility, increased intestinal permeability, and caused intestinal damage in weaned piglets. Meanwhile, a total of 174 differential proteins (DEPs) were identified between control and ZEN groups, with 60 up-regulated DEPs and 114 down-regulated DEPs (FC > 1.20 or <0.83, p < 0.05). Gene ontology analysis revealed that DEPs were mainly involved in substance transport and metabolism, gene expression, inflammatory, and oxidative stress. The Kyoto Encyclopedia of Genes and Genomes analysis revealed that DEPs were significantly enriched in 25 signaling pathways (p < 0.05), most of which were related to inflammation and amino acid metabolism. Our study provides valuable clues to elucidate the possible mechanism of ZEN-induced intestinal injury.


Assuntos
Zearalenona , Animais , Suínos , Zearalenona/análise , Proteômica , Desmame , Aminoácidos
2.
Anal Chim Acta ; 744: 75-81, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-22935377

RESUMO

A chemiluminescence (CL) array sensor for determination of benzenediol isomers simultaneously using the system of luminol-NaOH-H(2)O(2) based on a graphene-magnetite-molecularly imprinted polymer (GM-MIP) is described. Use of graphene in the GM-MIP thus prepared is helpful to improve the adsorption capacity, while use of magnetite nanoparticles can facilitate the isolation of GM-MIP at end of their synthesis, and rendering easier the use of the polymers in the array sensor. The adsorption performance and properties were characterized. The GM-MIP was used to increase the selectivity in CL analysis. In addition, the sensor was reusable and of good selectivity and adsorption capacity. The array sensor was finally used for the determination of hydroquinone, resorcinol and catechol in waste water samples simultaneously.


Assuntos
Catecóis/análise , Óxido Ferroso-Férrico/química , Grafite/química , Hidroquinonas/análise , Medições Luminescentes/métodos , Impressão Molecular , Resorcinóis/análise , Adsorção , Peróxido de Hidrogênio/química , Medições Luminescentes/instrumentação , Luminol/química , Polímeros/síntese química , Polímeros/química , Hidróxido de Sódio/química , Propriedades de Superfície
3.
Talanta ; 98: 226-30, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22939151

RESUMO

A new method for determination of L-tryptophan (L-try) using the flow injection chemiluminescence (FI-CL) system of KMnO(4)-SnCl(2)-CHOH based on a graphene oxide-magnetite-molecularly imprinted polymer (GM-MIP) is described. The L-try GM-MIP was synthesized using graphene oxide (G) which improved the adsorption capacity as carrier, and magnetite nanoparticles which made the polymers easier to use in the sensor. The adsorption performance and properties were characterized. The GM-MIP was used in CL analysis to increase the selectivity and the possible mechanism was also discussed. The CL sensor responded linearly to the concentration of L-try over the range from 2.10×10(-7) to 7.09×10(-4) M with a detection limit of 2.11×10(-8) M (3σ). The relative standard deviation (RSD) for the determination of 3.0×10(-5) M L-try was 2.40% (n=11). On the basis of speediness and sensitivity, the sensor is reusable and shows a great improvement in selectivity and adsorption capacity over other sensors. The sensor has been used for the determination of L-try in drug samples.


Assuntos
Óxido Ferroso-Férrico/química , Grafite/química , Impressão Molecular , Polímeros/química , Medicamentos sob Prescrição/química , Triptofano/análise , Adsorção , Análise de Injeção de Fluxo , Humanos , Limite de Detecção , Luminescência , Medições Luminescentes , Óxidos , Permanganato de Potássio/química , Compostos de Estanho/química
4.
Anal Bioanal Chem ; 404(1): 79-88, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22653423

RESUMO

This paper reports the preparation of dapsone (DDS) imprinted polymer layer-coated silica submicron particles (SiO(2)) combined with chemiluminescence (CL) toward analysis of tracing DDS in practical samples. To induce the selective occurrence of surface polymerization, the amino groups were first grafted at the surface of SiO(2) by the (3-aminopropyl)triethoxysilane (APTES). The molecularly imprinted polymers (MIP) were coated at the surface of modified SiO(2) by the graft copolymerization. After the removal of templates, recognition sites of DDS were exposed in the polymer layers. The DDS-imprinted products were characterized by FT-IR, SEM, TEM, dynamic adsorption, and static adsorption tests. The proximity between the thickness of MIP layer and the spatial size of DDS indicated that the imprinted sites almost situated at the surface of MIP, leading to rapid adsorption saturation within 90 min. The apparent maximum binding amount of MIP toward DDS was evaluated as 14.98 mg·g(-1), which was much higher than that of non-molecularly imprinted polymers. The CL sensor provided a wide linear range for DDS within 1.0 × 10(-6) to 1.0 × 10(-4) mol·L(-1) with a detection limit of 5.27 × 10(-7) mol·L(-1) and the relative standard deviation of 1.8 % (n = 11) by determinations of 5.0 × 10(-6) mol·L(-1) DDS. This method was applied to determine DDS in urine samples and satisfactory results were obtained.


Assuntos
Antibacterianos/análise , Técnicas Biossensoriais/métodos , Dapsona/análise , Análise de Injeção de Fluxo/métodos , Polímeros/química , Adsorção , Antibacterianos/urina , Técnicas Biossensoriais/instrumentação , Dapsona/urina , Análise de Injeção de Fluxo/instrumentação , Luminescência , Impressão Molecular , Polímeros/síntese química , Dióxido de Silício/química , Urina/química
5.
Bioresour Technol ; 114: 703-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22464421

RESUMO

A novel magnetic composite bioadsorbent composed of magnetic chitosan and graphene oxide (MCGO) was prepared as the magnetic adsorbent toward methylene blue. The magnetic composite bioadsorbent was characterized by SEM, FTIR and XRD measurements. The effect factors including pH, contact time and temperature on the adsorption properties of methylene blue onto MCGO were investigated. The resulting shows extraordinary adsorption capacity and fast adsorption rates for removal of methylene blue. The kinetics are well-described by pseudo-second-order kinetic. The experimental data of isotherm followed the Langmuir isotherm model and the Freundlich model, respectively. This work shows that the MCGO could be utilized as an efficient, magnetically separable adsorbent for the environmental cleanup.


Assuntos
Quitosana/química , Grafite/química , Nanopartículas de Magnetita/química , Azul de Metileno/química , Azul de Metileno/isolamento & purificação , Óxidos/química , Adsorção , Nanopartículas de Magnetita/ultraestrutura , Tamanho da Partícula
6.
Colloids Surf B Biointerfaces ; 95: 42-9, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22445236

RESUMO

The adsorption characteristics of hydroquinol from aqueous solutions onto the ß-cyclodextrin modified magnetic chitosan nanoparticles (CMCN) had been investigated. The characteristics results of FTIR, SEM and XRD showed that CMCN was successfully prepared. The influences of the pH of the solution and the contact time on the adsorption amounts had been discussed, and the appropriate process conditions for the adsorption of hydroquinol had been obtained. Equilibrium experiments fitted well with the Freundlich isotherm model, and the maximum adsorption capacity of the CMCN at 303 K was determined to be 1.75 mmol/g for hydroquinol at the concentration of 9.0 mmol/L, much higher than some conventional adsorbents. The CMCN was stable and easily recovered. Moreover, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Assuntos
Quitosana/química , Quitosana/síntese química , Hidroquinonas/química , Imãs/química , Nanopartículas/química , beta-Ciclodextrinas/química , Adsorção , Propriedades de Superfície
7.
J Hazard Mater ; 215-216: 272-9, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22429622

RESUMO

A novel magnetic composite bioadsorbent composed of magnetic chitosan and graphene oxide (MCGO) was prepared as the magnetic adsorbent. The morphology, chemical structure and magnetic property of the MCGO were characterized by Fourier transform infrared spectrometer (FT-IR), X-ray diffraction (XRD) and Scanning electronic microscope (SEM), respectively. Adsorption of methyl blue (MB) onto MCGO was investigated with respect to pH, adsorption time, initial MB concentration and temperature. Kinetics data and adsorption isotherm, obtained at the optimum pH 5.3, were better fitted by pseudo-second-order kinetic model and by Langmuir isotherm, respectively. The values of activation parameters such as free energy (ΔG, -0.74∼-1.46kJmol(-1)), enthalpy (ΔH, -10.28kJmol(-1)) and entropy (ΔS, -36.35Jmol(-1)K(-1)) were determined, respectively, indicating that the adsorption was spontaneous, favorable and exothermic process in nature. Moreover, the MCGO was stable and easily recovered, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Assuntos
Benzenossulfonatos/química , Quitosana/química , Grafite/química , Poluentes Químicos da Água/química , Adsorção , Magnetismo , Espectroscopia de Infravermelho com Transformada de Fourier , Purificação da Água/métodos , Difração de Raios X
8.
Anal Chim Acta ; 718: 84-91, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22305902

RESUMO

A novel flow injection chemiluminescence (FI-CL) sensor for determination of sulfadiazine (SDZ) using core-shell magnetic molecularly imprinted polymers (MMIPs) as recognition element is developed. Briefly, a hydrophilic MMIPs layer was produced at the surface of Fe(3)O(4)@SiO(2) magnetic nanoparticles (MNPs) via combination of molecular imprinting and reversible stimuli responsive hydrogel. And it provided the MMIPs with excellent adsorption capacity and rapid adsorption rate due to the imprinted sites mostly situated on the surface of MMIPs. Then the prepared SDZ-MMIPs were packed into flow cell to establish a novel FI-CL sensor. The sensor provided a wide linear range for SDZ of 4.0×10(-7) to 1.0×10(-4) mol L(-1) with a detection limit of 1.54×10(-7) mol L(-1). And the relative standard deviation (RSD) for the determination of 1.0×10(-6) mol L(-1) SDZ was 2.56% (n=11). The proposed method was applied to determine SDZ in urine samples and satisfactory results were obtained.


Assuntos
Anti-Infecciosos/análise , Análise de Injeção de Fluxo/instrumentação , Medições Luminescentes/instrumentação , Impressão Molecular , Nanopartículas/química , Sulfadiazina/análise , Desenho de Equipamento , Análise de Injeção de Fluxo/métodos , Limite de Detecção , Medições Luminescentes/métodos , Imãs/química , Nanopartículas/ultraestrutura , Polímeros/química
9.
Int J Biol Macromol ; 50(2): 444-50, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22227306

RESUMO

A novel nano-adsorbent, ß-cyclodextrin-chitosan (CDC) modified Fe(3)O(4) nanoparticles (CDCM) is fabricated for removal of methyl blue (MB) from aqueous solution by grafting CDC onto the magnetite surface. The characteristics results of FTIR, SEM and XRD show that CDC is grafted onto Fe(3)O(4) nanoparticles. The grafted CDC on the Fe(3)O(4) nanoparticles contributes to an enhancement of the adsorption capacity because of the strong abilities of CDCM, which includes the multiple hydroxyl, carboxyl groups, amino groups and the formation of an inclusion complex due to the ß-CD molecules through host-guest interactions, to adsorb MB. The adsorption of MB onto CDCM is found to be dependent on pH and temperature. Adsorption equilibrium is achieved in 50 min and the adsorption kinetics of MB is found to follow a pseudo-second-order kinetic model. Equilibrium data for MB adsorption are fitted well by Langmuir isotherm model. The maximum adsorption capacity for MB is estimated to be 2.78 g/g at 30°C. The CDCM was stable and easily recovered. Moreover the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used four times.


Assuntos
Benzenossulfonatos/química , Quitosana/química , Imãs , Nanopartículas Metálicas/química , beta-Ciclodextrinas/química , Adsorção , Quitosana/síntese química , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas Metálicas/ultraestrutura , Temperatura , Termodinâmica , beta-Ciclodextrinas/síntese química
10.
Artigo em Inglês | MEDLINE | ID: mdl-22112574

RESUMO

A novel molecular imprinting-chemiluminescence (MIP-CL) sensor for the determination of L-phenylalanine (Phe) using molecularly imprinted polymer (MIP) as recognition element is reported. The Phe-MIP was synthesized using acrylamide (AM) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker, 2,2-azobisisobutyronitrile (AIBN) as initiator and the polymers' properties were characterized. Then the synthesized MIP was employed as recognition element by packing into flow cell to establish a novel flow injection CL sensor. The CL intensity responded linearly to the concentration of Phe in the range 1.3 × 10(-6) to 5.44 × 10(-4) mol/L with a detection limit of 6.23 × 10(-7) mol/L (3σ), which is lower than that of conventional methods. The sensor is reusable and has a great improvement in sensitivity and selectivity for CL analysis. As a result, the new MIP-CL sensor had been successfully applied to the determination of Phe in samples.


Assuntos
Luminescência , Microesferas , Impressão Molecular/métodos , Sistemas On-Line , Fenilalanina/análise , Polímeros/química , Animais , Técnicas Biossensoriais , Análise de Injeção de Fluxo , Microscopia Eletrônica de Varredura , Leite/química , Fenilalanina/química , Reciclagem , Análise de Regressão , Espectrofotometria Infravermelho
11.
Colloids Surf B Biointerfaces ; 91: 250-7, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22119217

RESUMO

A novel, chitosan coating on the surface of magnetite (Fe(3)O(4)) (MIMC) was successfully synthesized using alizarin red (AR) as a template for adsorption and removal of AR from aqueous solutions. Characterization of the obtained MIMC was achieved by FTIR spectra, SEM micrographs and XRD. Batch adsorption experiments were performed to investigate the adsorption conditions, selectivity and reusability. The results showed that the maximum adsorption capacity was 40.12 mg/g, observed at pH 3 and temperature 30°C. Equilibrium adsorption was achieved within 50 min. The kinetic data, obtained at the optimum pH 3, could be fitted with a pseudo-second-order equation. Adsorption process could be well described by Langmuir adsorption isotherms and the maximum adsorption capacity was calculated as 43.08 mg/g. The selectivity coefficient of AR and other dyes onto MIMC indicated an overall preference for AR, which was much higher than non-imprinted magnetic chitosan beads. Moreover, the sorbent represented high stability and good repeatability.


Assuntos
Antraquinonas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
12.
J Hazard Mater ; 194: 193-201, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-21889845

RESUMO

A novel, thiourea-chitosan coating on the surface of magnetite (Fe(3)O(4)) (Ag-TCM) was successfully synthesized using Ag(I) as imprinted ions for adsorption and removal of Ag(I) ions from aqueous solutions. The thermal stability, chemical structure and magnetic property of the Ag-TCM were characterized by the scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometer (VSM), respectively. Batch adsorption experiments were performed to evaluate the adsorption conditions, selectivity and reusability. The results showed that the maximum adsorption capacity was 4.93 mmol/g, observed at pH 5 and temperature 30°C. Equilibrium adsorption was achieved within 50 min. The kinetic data, obtained at the optimum pH 5, could be fitted with a pseudo-second order equation. Adsorption process could be well described by Langmuir adsorption isotherms and the maximum adsorption capacity calculated from Langmuir equation was 5.29 mmol/g. The selectivity coefficient of Ag(I) ions and other metal cations onto Ag-TCM indicated an overall preference for Ag(I) ions, which was much higher than non-imprinted thiourea-chitosan beads. Moreover, the sorbent was stable and easily recovered, the adsorption capacity was about 90% of the initial saturation adsorption capacity after being used five times.


Assuntos
Quitosana/química , Magnetismo , Prata/isolamento & purificação , Água/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Temperatura , Difração de Raios X
13.
Colloids Surf B Biointerfaces ; 88(2): 574-81, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21868204

RESUMO

The performance of a cross-linked magnetic modified chitosan (CMMC), which has been coated with magnetic fluids and cross-linked with glutaraldehyde, has been investigated for the adsorption of Zn(2+) from aqueous solutions. The CMMC with a diameter range of 20-50 nm was prepared. The effects of pH and the contact time for the adsorption have been discussed, and the optimal adsorption conditions for the adsorption of Zn(2+) have been obtained. The research results showed that CMMC was highly efficient for fast adsorption of Zn(2+) within the first 25 min, and adsorption equilibrium could be achieved in 30 min. Equilibrium studies showed that the data of Zn(2+) adsorption followed the Langmuir model. The maximum adsorption capacity for Zn(2+) was estimated to be 32.16 mg/g with a Langmuir adsorption equilibrium constant of 0.01 L/mg at 298 K, which demonstrated that the CMMC had obvious efficient adsorption of Zn(2+). The CMMC was stable and easily recovered. Moreover, the adsorption rate was about 90% of the initial saturation adsorption capacity after being used five times.


Assuntos
Quitosana/química , Magnetismo , Água/química , Zinco/química , Adsorção , Concentração de Íons de Hidrogênio , Estrutura Molecular
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