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1.
Talanta ; 235: 122818, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517674

RESUMO

As a type of environmental endocrine disrupting chemicals, bisphenols (BPs) have a certain embryonic toxicity and teratogenicity, which can significantly increase the risks of breast cancer, prostate cancer, leukemia and other cancers. In this work, stable multivariate metal-organic frameworks (UiO-66-NH2/TCPPx) were synthesized via in situ one-pot method and used as miniaturized dispersive solid-phase extraction (dµSPE) sorbents for extraction of trace BPs from environmental samples. The phase purity, crystal morphology and physical properties of UiO-66-NH2/TCPPx samples were varied by adjusting the mass ratio of TCPP. The extraction performance of UiO-66-NH2/TCPPx samples were investigated and UiO-66-NH2/TCPP1.0 exhibited the highest adsorption efficiency. Besides, UiO-66-NH2/TCPP1.0 possessed excellent recycling stability for the adsorption and desorption of BPs more than 20 cycles. The experimental parameters including amount of adsorbent, adsorption time, sample solution pH, temperature, desorption time and desorption solvents which affecting the efficiency of dµSPE were studied, respectively. Good linearity (R2 > 0.9992) in range of 0.1-200 ng mL-1 was obtained. The detection limits (S/N = 3) and quantification limits (S/N = 10) were achieved at 0.03-0.08 ng mL-1 and 0.1-0.5 ng mL-1, respectively. The relative standard deviations (RSDs) of intra-day and inter-day ranged from 2.5 to 5.5% and 1.1-6.8%. Enrichment factors were calculated in the range of 303-338. The obtained recoveries of bisphenol F (BPF), bisphenol A (BPA), bisphenol B (BPB) and bisphenol AF (BPAF) were 81.26-91.03% (RSDs = 0.96-6.47%), 82.2-97.27% (RSDs = 0.45-6.15%), 87.56-97.26% (RSDs = 1.1-6.22%) and 82.2-100.8% (RSDs = 0.46-4.07%). The UiO-66-NH2/TCPP1.0 can be employed as potential dµSPE sorbents for the enrichment of trace BPs in the environmental samples.


Assuntos
Estruturas Metalorgânicas , Adsorção , Compostos Benzidrílicos , Humanos , Masculino , Fenóis , Extração em Fase Sólida , Solventes
2.
Mikrochim Acta ; 188(10): 340, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34523015

RESUMO

Using MIL-101(Fe) as the source of carbon and Fe, a magnetic porous carbon (MPC) material with Fe3C nanoparticles encapsulated in porous carbon was prepared through one-pot pyrolysis under N2 atmosphere. With MPC as adsorption material, a stir bar sorptive-dispersive microextraction (SBSDME) method was proposed to extract and preconcentrate sulfonamides (SAs) prior to HPLC-DAD determination. To investigate their extraction ability, different MPC materials were prepared under different carbonization temperatures (600, 700, 800, 900, and 1000 °C). The material prepared under 900 °C (MPC-900) exhibited the highest extraction ability for SAs. The as-prepared MPC materials were also characterized by Raman spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, zeta potential, and other techniques. The main parameters that affect extraction were systematically studied. Under optimal conditions, favorable linearity (R2 ≥ 0.9938) and detection limits (0.02-0.04 ng mL-1) of sulfonamides were obtained. The average recoveries for spiked milk and lake water samples ranged from 76.9 to 109% and from 75.4 to 118% with RSDs of 3.10-9.63% and 1.71-11.3%, respectively. Sulfameter and sulfisoxazole were detected in milk sample. Sulfisoxazole was detected in the lake water sample. The MPC-900 material demonstrated excellent reusability. It can be reused 24 times with peak areas having no obvious decline. The method can be applied to extract ultra-trace compounds in complex sample matrices. Schematic presentation of a stir bar sorptive-dispersive microextraction (SBSDME) by using magnetic porous carbon (MPC) composites as sorbent combined with high-performance liquid chromatography for sensitive analysis of sulfonamides in milk and lake water samples.

3.
Chem Commun (Camb) ; 57(70): 8810-8813, 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34382969

RESUMO

Herein, a new gas-cycle-assisted (GCA) headspace solid-phase microextraction (HS-SPME) device was designed to rapidly extract organic pollutants with high Kow and boiling points, which have difficulty in volatilization from matrix to headspace. Organic pollutants, including three polycyclic aromatic hydrocarbons (PAHs), four polychlorinated biphenyls (PCBs), and five phthalate esters (PAEs), were selected to evaluate the performance of GCA HS-SPME. Compared with conventional HS-SPME, the equilibrium times of GCA HS-SPME for extraction of PAHs, PCBs, and PAEs were greatly shortened from 70-90 to 5-11 min. Moreover, the limits of detection for analysis of PAHs were achieved at pg mL-1 level by GCA HS-SPME coupled with gas chromatography-flame ionization detection.

4.
J Chromatogr A ; 1626: 461354, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797834

RESUMO

The Al-doped mesoporous crystalline material-41 (Al-MCM-41) composite was prepared and applied as fiber coating material of headspace solid-phase microextraction (HS-SPME) for extraction of polycyclic aromatic hydrocarbons (PAHs) from human urine. Five PAHs including acenaphthene, fluorene, phenanthrene, anthracene, and pyrene are chosen as target analytes to evaluate the performance of the material by GC-FID analysis. The mesoporous Al-MCM-41 composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption measurement, and thermogravimetric analysis. The parameters affecting the extraction efficiency of HS-SPME were investigated. Under the optimal conditions, the method exhibits ideal linearity for target analytes in the range of 0.3-600 ng⋅mL-1 with the coefficients (R2) equal or higher than 0.9906. The enrichment factors are calculated from 540 to 1760. The limits of detection (LODs) and limits of quantitation (LOQs) are between the ranges of 0.06-0.18 and 0.3-0.9 ng⋅mL-1, respectively. The relative standard deviations (RSDs) (n = 5) of intra-day and inter-day are in the ranges of 1.08-7.49% and 2.84-18.3% respectively. The fiber-to-fiber reproducibility (n = 3) is in the range of 6.47-13.9%. The method was successfully applied for the analysis of PAHs in human urine with reasonable recoveries which is ranging from 73.29 to 116.1%.


Assuntos
Alumínio/química , Hidrocarbonetos Policíclicos Aromáticos/urina , Dióxido de Silício/química , Microextração em Fase Sólida/métodos , Adsorção , Cristalização , Humanos , Limite de Detecção , Masculino , Concentração Osmolar , Porosidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
5.
Mikrochim Acta ; 187(6): 367, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32494885

RESUMO

The monodispersed mesoporous SiO2@metal-organic framework (MSN@MIL-101(Fe)) composites were prepared by grafting MSN-NH2 onto MIL-101(Fe) particles with a solvothermal method. The adsorption ability of the composites was greatly improved compared to that of pristine MSNs or MIL-101(Fe) for phytohormones (Phys). The MSN@MIL-101(Fe) composites were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive spectrometer, and mapping analysis. Using MSN@MIL-101(Fe) composites as sorbent, a dispersive solid-phase extraction procedure (dSPE) was developed to extract three endogenous Phys (abscisic acid (ABA), indole-3-aceticacid (IAA), and indole-3-butyric acid (IBA)) and two exogenous Phys (1-naphthylacetic acid (1-NAA) and 2-naphthylacetic acid (2-NAA)) prior to HPLC-DAD analysis. The experimental parameters including sample volume, sorbent amount, adsorption time, adsorption pH, desorption time, and desorption solvent on extraction efficiency were optimized and evaluated. Under optimized conditions, the working range of 0.08 to 0.45 ng mL-1 with enrichment factors from 144 to 207 were achieved. The linear range is 0.75-200 ng mL-1 for IAA, 0.20-200 ng mL-1 for ABA, and 1.0-200 ng mL-1 for IBA, 1-NAA, and 2-NAA. With MSN@MIL-101(Fe) as sorbent for extraction of Phys and determination by HPLC-DAD, two endogenous Phys (IAA and ABA) were detected from mung bean sprouts which were made in a laboratory, and the results were further confirmed by high-resolution mass spectrometry. The composites can be applied to extract other small molecules, which have similar chemical structures with Phys in biological, environmental, and food samples. Graphical abstract Schematic presentation of a dispersive solid-phase extraction using monodispersed mesoporous SiO2@metal-organic framework composites (MSNs@MIL-101(Fe)) as the sorbent for extraction, clean-up, and preconcentration of phytohormones in mung bean sprouts prior to HPLC-DAD analysis.

6.
Talanta ; 208: 120440, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816803

RESUMO

Reduced graphene oxide/ZnFe2O4 (rGO/ZnFe2O4) nanocomposite was facile prepared and applied as magnetic sorbent for the extraction of estrogens including 17ß-estradiol, 17α-estradiol, estrone and hexestrol from water, soil, and fish samples prior to HPLC analysis. The rGO/ZnFe2O4 nanocomposite was characterized by scanning electron microscope, Fourier transform-infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. The experimental parameters affecting the efficiency of magnetic solid-phase extraction (MSPE) including the amount of material, extraction time, pH, temperature, desorption solvents, desorption time, and desorption solvent volume were investigated respectively. With the developed method, good linearity was observed in the range of 0.05-500 ng/mL with the correlation coefficients (R2) between 0.9978 and 0.9993. The limits of detection (S/N = 3) and limits of quantification (S/N = 10) were achieved at 0.01-0.02 ng/mL and 0.05 ng/mL, respectively. The enrichment factors were calculated as the range of 241-288. Using rGO/ZnFe2O4 nanocomposite as the sorbent, the developed MSPE followed by HPLC analysis, was applied to analysis of estrogens in river water, soil and fish samples. The method has the potential application in the extraction and preconcentration ultra trace compounds in complex matrices, such as environmental and biological samples.


Assuntos
Estrogênios/química , Compostos Férricos/química , Grafite/química , Nanocompostos/química , Zinco/química , Adsorção , Animais , Peixes , Fenômenos Magnéticos , Solo/química , Água/química
7.
Chem Commun (Camb) ; 55(67): 10019-10022, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31378803

RESUMO

We report a facile hydrothermal method to synthesize a novel mesoporous graphitic carbon nitride (MCN)@NiCo2O4 nanocomposite, which can be used as a solid phase microextraction coating for high efficiency extraction and preconcentration of trace polychlorinated biphenyls and polycyclic aromatic hydrocarbons in human serum samples.


Assuntos
Poluentes Ambientais/sangue , Nanocompostos/química , Nitrilas/química , Bifenilos Policlorados/sangue , Hidrocarbonetos Policíclicos Aromáticos/sangue , Cobalto/química , Humanos , Limite de Detecção , Níquel/química , Microextração em Fase Sólida/instrumentação , Microextração em Fase Sólida/métodos
8.
Mikrochim Acta ; 186(5): 279, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30976897

RESUMO

Mesoporous graphitic carbon nitride (MCN) is shown to be a viable sorbent for the enrichment of sulfonamides (SAs). To overcome the difficulty of separating the sorbent from the matrix, a novel type kind of column-assisted dispersive solid-phase extraction (CA-dSPE) method was designed. The MCN was characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy and nitrogen adsorption-desorption measurements. The amount of sorbent, the pH value of the sample, the adsorption time, type and volume of the eluent and desorption time were optimized. The SAs were eluted from the sorbent with elution solvent of methanol containing 10% (v/v) ammonia and then submitted to HPLC analysis. Under the optimized conditions, the limits of detection for the SAs investigated (sulfadiazine, sulfameter, sulfachloropyridazine, sulfabenzamide and sulfadimethoxine) range from 20 to 5 pg·mL-1. Satisfactory recoveries were obtained for spiked environmental water (90.1-110.5%) and milk samples (82.3-102.7%), with relative standard deviations of 0.5-3.8% and 1.1-4.4%, respectively. The method is simple, time saving and sensitive. Graphical abstract Schematic presentation of a column assisted dispersive solid-phase extraction by using mesoporous graphitic carbon nitride as sorbent combined with high performance liquid chromatography for sensitive analysis of sulfonamides in environmental water and milk samples.

9.
Artigo em Inglês | MEDLINE | ID: mdl-30352014

RESUMO

This work presents a method of magnetic solid-phase extraction (MSPE) combined with high-performance liquid chromatography (HPLC) to analyse five synthetic azo dyes (tartrazine, amaranth, carmine, sunset yellow, allura red) in different food samples. The magnetic graphene oxide nanocomposite (GO@Fe3O4) was prepared by a one-step solvothermal method and used as the sorbent for extraction and pre-concentration of azo dyes in food samples. The as-prepared GO@Fe3O4 nanocomposite was characterised by transmission electron microscope, Fourier transform-infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, and Brunuer-Emmett-Teller analysis. The extraction and desorption parameters were investigated, including the material amount, extraction time, pH of the solution, desorption temperature, and desorption solvents. Under the optimised conditions, the limits of detection (LODs) were 1.14-2.23, 0.36-0.77 and 0.68-1.26 ng/g for candy, jelly, and plum candy, respectively. The limits of quantification (LOQs) were 4.02-7.73, 1.21-2.50 and 2.31-4.20 ng/g for candy, jelly, and plum candy, respectively. For the analysis of spiked jelly, recoveries were between 73.2% and 107.7%, with RSDs lower than 1.34 %. The developed method was successfully applied to the analysis of real samples including jelly, candy and plum candy.


Assuntos
Compostos Azo/análise , Análise de Alimentos , Contaminação de Alimentos/análise , Grafite/química , Nanopartículas de Magnetita/química , Óxidos/química , Adsorção , Cromatografia Líquida de Alta Pressão , Propriedades de Superfície
10.
J Chromatogr A ; 1570: 47-55, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30078480

RESUMO

In this work, a novel nanoscale graphitic carbon nitride hybridized with copper oxide (nano-g-C3N4/CuO) composite was prepared and used as the coating of solid-phase microextraction (SPME) for the first time. The coating was applied to adsorption and preconcentration of polycyclic aromatic hydrocarbons (PAHs) including naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, and pyrene from water and soil prior to gas chromatography (GC) analysis. Compared with pristine nanoscale graphitic carbon nitride (nano-g-C3N4) or copper oxide (CuO), the as-prepared nano-g-C3N4/CuO composite as the coating of SPME provided the best adsorption affinity for PAHs. Moreover, the extraction efficiencies of the nano-g-C3N4/CuO coated fibers were much higher than that of bulk-g-C3N4/CuO hybrids. The developed method exhibited excellent linearity for target analytes in the range of 0.1-1000 ng/mL with determination coefficient (R2) not lower than 0.9944. The limits of detection (LODs) of the established method for the analysis of PAHs were achieved between 0.025 and 0.40 ng/mL. The relative standard deviations (RSDs) for three replicate extractions with one fiber were determined from 2.5% to 7.3%. The fiber-to-fiber reproducibility (n = 3) was 5.4-12.8%. The prepared coating also demonstrated excellent thermal and chemical stability. The method was successfully applied to analysis of target analytes in water and soil samples and the corresponding contents were calculated between 0.07 and 1.58 µg/g.


Assuntos
Cromatografia Gasosa/métodos , Cobre/química , Grafite/química , Nanocompostos/química , Nitrilas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Microextração em Fase Sólida/métodos , Adsorção , Limite de Detecção , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
11.
Nanomaterials (Basel) ; 7(4)2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28430138

RESUMO

Matrix-assisted laser desorption/ionization (MALDI), a soft ionization method, coupling with time-of-flight mass spectrometry (TOF MS) has become an indispensible tool for analyzing macromolecules, such as peptides, proteins, nucleic acids and polymers. However, the application of MALDI for the analysis of small molecules (<700 Da) has become the great challenge because of the interference from the conventional matrix in low mass region. To overcome this drawback, more attention has been paid to explore interference-free methods in the past decade. The technique of applying nanomaterials as matrix of laser desorption/ionization (LDI), also called nanomaterial-assisted laser desorption/ionization (nanomaterial-assisted LDI), has attracted considerable attention in the analysis of low-molecular weight compounds in TOF MS. This review mainly summarized the applications of different types of nanomaterials including carbon-based, metal-based and metal-organic frameworks as assisted matrices for LDI in the analysis of small biological molecules, environmental pollutants and other low-molecular weight compounds.

12.
Nanomaterials (Basel) ; 8(1)2017 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-29295535

RESUMO

In this work, a highly efficient and rapid method for simultaneously removing cationic dyes from aqueous solutions was developed by using monodispersed mesoporous silica nanoparticles (MSNs) as the adsorbents. The MSNs were prepared by a facile one-pot method and characterized by scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, and Brunauer-Emmett-Teller. Experimental results demonstrated that the as-prepared MSNs possessed a large specific surface area (about 585 m²/g), uniform particle size (about 30 nm), large pore volume (1.175 cm³/g), and narrow pore size distribution (1.68 nm). The materials showed highly efficient and rapid adsorption properties for cationic dyes including rhodamine B, methylene blue, methyl violet, malachite green, and basic fuchsin. Under the optimized conditions, the maximum adsorption capacities for the above mentioned cationic dyes were in the range of 14.70 mg/g to 34.23 mg/g, which could be achieved within 2 to 6 min. The probable adsorption mechanism of MSNs for adsorption of cationic dyes is proposed. It could be considered that the adsorption is mainly controlled by electrostatic interactions and hydrogen bonding between the cationic dyes and MSNs. As a low-cost, biocompatible, and environmentally friendly material, MSNs have a potential application in wastewater treatment for removing some environmental cationic contaminants.

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