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1.
Top Curr Chem (Cham) ; 377(6): 32, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31654264

RESUMO

Metal-organic frameworks (MOFs) are an emerging class of porous crystalline materials attracting attention for their vast array of topologies as well as potential applications in gas storage, heterogeneous catalysis, and molecular sensing. In most cases, organocarboxylates (or corresponding carboxylic acids) are the most common building block, achieving well-defined metal-carboxylate coordination motifs in MOF structures. However, organosulfonates (or corresponding sulfonic acids) have been less well studied in MOF chemistry, probably owing to the weak coordination tendency of the sulfonate oxygens toward metal centers. This review summarizes the research on organosulfonate-based porous crystalline MOFs in recent years. The construction of most porous organosulfonate MOFs relies on using either a second N-donor ligand or carboxylate-sulfonate bifunctional ligands. Despite occupying more confined porosity than the carboxylate counterpart, the permanent porosity in organosulfonate MOFs is often highly polar and hydrophilic. Thus, organosulfonate MOFs often exhibit improved proton/Li+ conductivity as well as CO2 affinity compared with their carboxylate-based counterparts. In addition, the application of organosulfonate MOFs in molecular sensing, molecular sieving, catalysis, and anion exchange are discussed in this review as well.


Assuntos
Estruturas Metalorgânicas/química , Ácidos Sulfônicos/química , Dióxido de Carbono/química , Ácidos Carboxílicos/química , Catálise , Estruturas Metalorgânicas/síntese química , Porosidade
2.
Top Curr Chem (Cham) ; 377(6): 33, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664531

RESUMO

Separation of hydrocarbon mixtures into single components is a very important industrial process because all represent very important energy resources/raw chemicals in the petrochemical industry. The well-established industrial separation technology highly relies on the energy-intensive cryogenic distillation processes. The discovery of new materials capable of separating hydrocarbon mixtures by adsorbent-based separation technologies has the potential to provide more energy-efficient industrial processes with remarkable energy savings. Porous metal-organic frameworks (MOFs), also known as porous coordination polymers, represent a new class of porous materials that offer tremendous promise for hydrocarbon separations because of their easy tunability, designability, and functionality. A number of MOFs have been designed and synthesized to show excellent separation performance on various hydrocarbon separations. Here, we summarize and highlight some recent significant advances in the development of microporous MOFs for hydrocarbon separation applications.


Assuntos
Hidrocarbonetos/isolamento & purificação , Estruturas Metalorgânicas/química , Alcenos/química , Alcenos/isolamento & purificação , Etilenos/química , Etilenos/isolamento & purificação , Hidrocarbonetos/química , Parafina/química , Parafina/isolamento & purificação , Porosidade
3.
Top Curr Chem (Cham) ; 377(6): 34, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31664532

RESUMO

Given the unique properties of metal-organic frameworks (MOFs) including adjustable porosity, high surface area, and easy modification, they have attracted great attention as excellent solid supports for the incorporation of biomolecules. The formed biomolecules-MOFs composites show promising prospects in various fields such as biocatalysis, drug delivery, and biosensing. This review focuses on the state-of-the-art of biomolecules-incorporation using MOFs. Moreover, the relationship between properties of MOFs and biomolecules-incorporation is also discussed and highlighted. We hope this work will inspire the innovation in this emerging field for highly efficient synthesis of biomolecules-MOFs composites with various properties and advanced applications.


Assuntos
Estruturas Metalorgânicas/química , Adsorção , DNA/química , Porosidade , Proteínas/química , Propriedades de Superfície
4.
Top Curr Chem (Cham) ; 377(5): 25, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529217

RESUMO

Metal-organic frameworks (MOFs) have gathered tremendous interest among researchers for their potential applications such as in storage and separation. While some progress has been made towards shaping of MOFs to realize industrial applications, the mechanical properties of MOFs remain more or less unexplored. Over the last decade, this area has witnessed a steady growth in terms of understanding the mechanical stability of MOFs and its consequence on their performance. In this review, the mechanical properties of the reported macroscopic shaped MOF structures (mainly granules, pellets, tablets, monoliths, and gels) are discussed. Conclusions are then drawn to determine which shapes and shaping techniques promise to meet industrial requirements on the basis of mechanical stability. Finally, future research directions are proposed to improve our understanding, and possibly enhance stability, by correlating the properties from microscopic single-crystalline level to the industrially relevant macroscopic polycrystalline scale.


Assuntos
Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
5.
J Chromatogr A ; 1604: 460465, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31477277

RESUMO

A new analytical method based on the recently proposed stir bar sorptive-dispersive microextraction (SBSDME) technique has been developed to determine eight hazardous N-nitrosamines in cosmetic products. As previous step, a simple clean-up is carried out with hexane to remove those highly lipophilic compounds that disturb the SBSDME step. Subsequently, SBSDME is performed by using magnetic nanoparticles-metal organic framework composite, CoFe2O4/MIL-101(Fe), as sorbent to entrap the target analytes, which are later chemically desorbed and measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The experimental variables related to the SBSDME procedure were studied to achieve the highest analytical signal. Under the most favorable conditions, the proposed method was validated providing good linearity; enrichment factors up to 62 depending on the analyte; limits of detection from 3 to 13 µg kg-1; and good repeatability values (RSD < 17.0%). Finally, the method was successfully applied to cosmetic samples composed either of lipophilic or hydrophilic matrices. Quantitative relative recoveries (96-109%) were obtained by using standard addition calibration. The present work expands the applicability of the SBSDME technique, whereas its analytical features make it useful to carry out the quality control of cosmetic samples.


Assuntos
Técnicas de Química Analítica/métodos , Cosméticos/química , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Nitrosaminas/análise , Cromatografia Líquida , Cosméticos/normas , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Microextração em Fase Líquida , Espectrometria de Massas em Tandem
6.
Anal Chim Acta ; 1083: 101-109, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31493800

RESUMO

In this work, a facile ratiometric electrochemical aptasensor was developed towards sensitive and selective detection of vanillin, based on Ketjen black/ferrocene dual-doped zeolite-like MOFs (Fc-KB/ZIF-8) and electrodeposited gold nanoparticles (AuNPs) coupling with DNA aptamer. Fc-KB/ZIF-8 composites were prepared via one-pot solvothermal reaction and drop-coated on glassy carbon electrode (GCE) surface to form Fc-KB/ZIF-8@GCE. AuNPs were in-situ electro-deposited on the modified GCE. 5'-SH terminated aptamer of vanillin was combined with AuNPs via Au-S coupling to form aptamer-AuNPs/Fc-KB/ZIF-8@GCE as a new sensing platform. Under optimal conditions, electrochemical (square wave voltammetry) curves of this sensing platform were measured in electrolyte solutions containing vanillin. With increase of vanillin concentration (Cvan), vanillin had an increased peak current intensity (Ivan, as response signal). Fc doped into ZIF-8 had slight changes in its peak current intensity (IFc, as reference signal). There is a well plotting linear relationship between Ivan/IFc and the logarithm of Cvan ranging from 10 nM to 0.2 mM, with a low limit of detection of 3 nM. The aptamer-AuNPs/Fc-KB/ZIF-8@GCE was applied as a ratiometric electrochemical aptasensor of vanillin. This aptasensor had sensitive and selective electrochemical signal responses on vanillin, over potential interferents. This aptasensor enabled vanillin detection in real food samples, showing high detection performance. Experimental results testified that this aptasensor had high reliability and practicability for vanillin determination in real samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Benzaldeídos/análise , DNA/química , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Benzaldeídos/química , Doces/análise , Carbono/química , Chocolate/análise , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Compostos Ferrosos/química , Análise de Alimentos/métodos , Ouro/química , Limite de Detecção , Metalocenos/química
7.
Artigo em Inglês | MEDLINE | ID: mdl-31479387

RESUMO

An extraction method based on metal-organic framework has been developed and applied to acetanilide herbicides, including metazachlor, propanil, pretilachlor, and butachlor, in black beans, red beans, and kidney beans. The acetanilide herbicides are extracted with a mixture of ethyl acetate and n-hexane. The extract solution is absorbed and purified with metal-organic framework MIL-101 (Zn). The separation and determination of four acetanilide herbicides were implemented by high-performance liquid chromatography. The experimental parameters were evaluated by a univariate method and orthogonal experiments. The presented method can obtain effective extraction and purification. The detection limits for metazachlor, propanil, pretilachlor, and butachlor were 0.58, 0.90, 1.78 and 1.18 µg/kg, respectively. The average recoveries of the acetanilide herbicides at spiked concentrations of 10, 50, and 100 µg/kg ranged from 86.9% to 119.0%, and relative standard deviations were equal to or lower than 2.80%.


Assuntos
Acetanilidas/isolamento & purificação , Herbicidas/isolamento & purificação , Estruturas Metalorgânicas/química , Acetanilidas/química , Acetatos/química , Adsorção , Animais , Canavalia/química , Herbicidas/química , Hexanos/química , Tamanho da Partícula , Phaseolus/química
8.
Inorg Chem ; 58(19): 12700-12706, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31556291

RESUMO

The highly porous luminescent metal-organic frameworks (MOFs) can act as fluorescent probes for the detection of nitro compounds and can also serve as containers and energy transfer platforms to construct the host-guest systems. Herein, two new three-dimensional MOFs with high porosity were prepared successfully by the electron-rich tetrakis(4-pyridylphenyl)ethylene (tppe) as ligands. Compound 1 shows the high sensitivity and selectivity toward nitro-antibiotics in an aqueous media, particularly showing the best detection efficiency for furazolidone (FZD) among the reported luminescent sensors. The highly efficient fluorescence quenching toward FZD may be attributed to the electron and energy transfer. Compound 2 has naphthalene-2,7-dicarboxylic acid (2,7-npd) and tppe as dual linkers, and the energy transfer between 2,7-npd and tppe leads to the emission band in a large scale. It is worth noting that the single-phased white-light materials can be obtained by the in situ encapsulation of different concentration of sulforhodamine 101 (SR101) into compound 2 matrix.


Assuntos
Antibacterianos/análise , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Nitrocompostos/análise , Estilbenos/química , Cristalografia por Raios X , Luminescência , Medições Luminescentes , Modelos Moleculares , Rodaminas/química
9.
Inorg Chem ; 58(17): 11382-11388, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31402664

RESUMO

Enzyme-like metal-organic frameworks (MOFs) are currently one type of starring material in the fields of artificial enzymes and analytical sensing. However, there has been little progress in making use of the MOF structures based on the catalytically active metal center with multiple valences. Herein, we report a mixed-valence Ce-MOF (Ce-BPyDC) that can exhibit both oxidase-like and peroxidase-like activities. Ce-BPyDC was synthesized by a facile hydrothermal method, which preserves the rare coexistence of Ce(III) and Ce(IV) in the MOF structure. The enzymatic studies demonstrated the enzyme-like activities of Ce-BPyDC follow the Michaelis-Menten kinetics and are strongly dependent on temperature, pH, and reaction time. Ce-BPyDC was also revealed to exert high catalytic activity that could transcend horseradish peroxidase and other MOF nanozymes, due to the redox-active Ce(III)/Ce(IV) cycles inside. Furthermore, the simple synthesis, high nanozyme activity, and great stability of Ce-BPyDC motivated us to establish a colorimetric biosensing platform using 3,3',5,5'-tetramethylbenzidine as a color reagent. Adopting this strategy, we established a visual, sensitive, and selective colorimetric method for ascorbic acid (AA) detection, for which the linear interval and limit of detection were 1-20 and 0.28 µM, respectively. The successful AA detection in real juice samples implies the promising use of such mixed-valence MOF nanozymes in food and biomedical samples.


Assuntos
Técnicas Biossensoriais , Cério/química , Colorimetria , Estruturas Metalorgânicas/química , Ácido Ascórbico/análise , Catálise , Concentração de Íons de Hidrogênio , Estruturas Metalorgânicas/síntese química , Temperatura Ambiente
10.
Chem Commun (Camb) ; 55(72): 10792-10795, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31432816

RESUMO

Hypoxia, as an important feature in tumor sites, greatly hinders the performance of photosensitizers, thus affecting the efficacy of photodynamic therapy (PDT). Therefore, designing and preparing new photosensitizer with high photosensitivity under hypoxic condition presents a great challenge that urgently needs to be solved. In this work, a new nano-MOF material using Mn(ii) as the active center can catalytically decompose high concentrations of H2O2 in tumor cells to generate O2, thereby improving the PDT efficacy in hypoxic tumors. The Mn-MOF also produces 1O2 under light irradiation, which finally induces cancer cell apoptosis. This work offers a new strategy for the design and discovery of effective photosensitizers for PDT.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Manganês/farmacologia , Estruturas Metalorgânicas/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Hipóxia Tumoral/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Peróxido de Hidrogênio/metabolismo , Manganês/química , Estruturas Metalorgânicas/química , Camundongos , Oxigênio/metabolismo , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Propriedades de Superfície
11.
Chem Commun (Camb) ; 55(72): 10772-10775, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31432820

RESUMO

Herein, a novel photoelectrochemical (PEC) assay was developed for the sensitive detection of C-reactive protein (CRP) based on a zirconium-based metal-organic framework (PCN-777) as the photoelectric material and thioflavin-T (Th-T) as the effective signal sensitizer coupled with rolling circle amplification (RCA).


Assuntos
Benzotiazóis/química , Técnicas Biossensoriais , Proteína C-Reativa/análise , Técnicas Eletroquímicas , Estruturas Metalorgânicas/química , Zircônio/química , Humanos , Processos Fotoquímicos
12.
Ecotoxicol Environ Saf ; 183: 109546, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31437727

RESUMO

A ß-cyclodextrin-functionalized magnetic zinc-metal organic framework (M-MOF/ß-CD) was synthesized via a facile one-pot reaction. M-MOF/ß-CD was used as a magnetic porous absorbent for the extraction and determination of prochloraz and three triazole fungicides in vegetable samples. M-MOF/ß-CD was prepared by creating MOF layers on the surface of a Fe3O4-graphene oxide (GO) nanocomposite and bonding them with ß-CD molecules. Characterization suggested that a 3D porous structure was formed, with M-MOF/ß-CD exhibiting high superparamagnetism and a large surface area. As a new strategy, integrating MOFs with Fe3O4-GO could improve their water-resistance and mechanical strength by providing a rigid nanosupport interface. Combining M-MOF and ß-CD resulted in excellent selective adsorption capacities for prochloraz and three triazole fungicides. The static adsorption process was evaluated and the results were in good agreement with the Freundlich model. Subsequently, M-MOF/ß-CD was applied to extracting prochloraz and triazole fungicides from tomato and lettuce vegetables, followed by HPLC-MS/MS determination. The limits of detection for the above fungicides were found to be 0.25-1.0 µg/L at a signal-to-noise ratio of 3, with spiked recoveries of 74.13%-119.83%, indicating that M-MOF/ß-CD was promising for application to the extraction and determination of fungicides in complex matrices.


Assuntos
Fungicidas Industriais/análise , Imidazóis/análise , Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Triazóis/análise , Verduras/química , beta-Ciclodextrinas/química , Adsorção , Grafite/química , Limite de Detecção , Nanocompostos/química , Porosidade , Reprodutibilidade dos Testes , Propriedades de Superfície
13.
Bioelectrochemistry ; 130: 107348, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31437810

RESUMO

A practical electrochemical biosensor with high sensitivity was developed for detecting organophosphorus (OP). Initially, Ce metal was introduced into an UiO-66-template to form Ce/UiO-66. Later, graphene oxide (GO), carbon black (CB) and multi-walled carbon nanotubes (MWCNTs) were separately added to Ce/UiO-66 to compare the effect of different carbon-based material types on the performance of the biosensor. Exclusively, Ce/UiO-66/MWCNTs with a Ce (7%) and MWCNT (30%) matrix was found to not only load more acetylcholinesterase (AChE) onto vacant sites but also increase electron transfer and decrease the number of diffusion pathways between the thiocholine and electrode surface. Moreover, the appropriate oxophilicity of Ce coupled with the high surface area and good conductivity of MWCNTs in the UiO-66 structure revealed a high affinity to acetylthiocholine chloride (ATCl) and possible catalysis of the hydrolysis of ATCl with a Michaelis-Menten constant of 0.258 mM. This biosensor, under optimal conditions, demonstrated a rapid and sensitive detection of paraoxon over a wide linear range of 0.01-150 nM, with a low detection limit of 0.004 nM. As a result, the AChE/Ce/UiO-66/MWCNTs/GCE biosensor can be employed in laboratory and field experiments to determine paraoxon levels.


Assuntos
Técnicas Biossensoriais/métodos , Cério/química , Estruturas Metalorgânicas/química , Paraoxon/análise , Praguicidas/análise , Acetilcolinesterase/química , Animais , Brassica/química , Electrophorus , Enzimas Imobilizadas/química , Proteínas de Peixes/química , Grafite/química , Modelos Moleculares , Nanotubos de Carbono/química , Spinacia oleracea/química
14.
Phys Chem Chem Phys ; 21(35): 19226-19233, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31441492

RESUMO

As one of the main air pollutants, nitrogen oxides (NOx) have serious effects on human health and the environment. In our previous study, we found that Mn-MOF-74 shows excellent catalytic performance for the selective catalytic reduction (SCR) reaction with NH3 being the reductant (NH3-SCR) at low temperature. To obtain a further understanding of the NH3-SCR mechanism in Mn-MOF-74, in this paper, we investigated two important parts of the NH3-SCR process in Mn-MOF-74 using the density functional theory (DFT) method. On the one hand, the structural characteristics of two types of oxygen vacancies of Mn-MOF-74, namely carboxyl oxygen vacancies and hydroxyl oxygen vacancies, and their adsorption properties to reaction species were calculated. It was found that the oxygen vacancies not only activate the reaction species, but also promote the desorption of NO2 molecules from metal sites for the subsequent rapid SCR reactions. On the other hand, we studied the effect of H2O on the structural stability and catalytic performance of Mn-MOF-74. It was found that the interaction of Mn-O bonds was weakened by H2O. Therefore, the influence of H2O should be considered for the future design of MOF-based catalysts for the SCR process.


Assuntos
Teoria da Densidade Funcional , Estruturas Metalorgânicas/química , Oxigênio/química , Água/química , Poluentes Atmosféricos/química , Poluentes Atmosféricos/isolamento & purificação , Catálise , Óxidos de Nitrogênio/química , Óxidos de Nitrogênio/isolamento & purificação , Substâncias Redutoras/química
15.
Chemosphere ; 235: 527-537, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31276866

RESUMO

Pharmaceutical products (PhACs) in water sources are considered to be a severe environmental issue. To mitigate this issue, we used a metal-organic framework (MOF) as an adsorbent to remove selected PhACs (i.e., carbamazepine (CBM) and ibuprofen (IBP)). This work was carried out to characterize the MOF, then confirm its feasibility for removing the selected PhACs. In particular, based on practical considerations, we investigated the effects of various water quality conditions, such as solution temperature, pH, ionic strength/background ions, and humic acid. MOF exhibited better removal rates than commercial powder activated carbon (PAC), considering pseudo-second order kinetic model. We clarified the competitive PhACs adsorption mechanisms based on the results obtained under various water quality conditions and found that hydrophobic interactions were the most important factors for both adsorbates. To confirm the practicality of MOF adsorption, we carried out regeneration tests with four adsorption and desorption cycles using acetone as a cleaning solution. Furthermore, to support the results of our regeneration tests, we characterized the MOF samples before and after adsorbate exposure using Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Overall, MOF can be used in practical applications as efficient adsorbents to remove PhACs from water sources.


Assuntos
Carbamazepina/química , Ibuprofeno/química , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Carbamazepina/análise , Carvão Vegetal , Substâncias Húmicas , Interações Hidrofóbicas e Hidrofílicas , Ibuprofeno/análise , Cinética , Estruturas Metalorgânicas/análise , Concentração Osmolar , Água/química , Poluentes Químicos da Água/análise
16.
Environ Pollut ; 252(Pt B): 1574-1581, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31277026

RESUMO

The bioavailability of a pollutant is usually evaluated based on its freely dissolved concentration (Cfree), which can be measured by negligible-depletion equilibrium extraction that is commonly suffered from long equilibration time. Herein, metal-organic framework (MOF) composites (Fe3O4@MIL-101), consists of a magnetic Fe3O4 core and a MIL-101 (Cr) MOF shell, is developed as sorbents for negligible-depletion magnetic solid-phase extraction (nd-MSPE) of freely dissolved polyaromatic hydrocarbons (PAHs) in environmental waters. The freely dissolved PAHs in 1000 mL water samples are extracted with 1.5 mg MOF composites, and desorbed with 0.9 mL of acetonitrile under sonication for 5 min. The MOF composites exclude the extraction of dissolved organic matter (DOM) and DOM-associated PAHs by size exclusion. Additionally, the combined interactions (hydrophobic, π-π and π-complexation) between PAHs and composites markedly reduced the extraction equilibration time to < 60 min for all the studied PAHs with logKOW up to 5.74. Moreover, the porous coordination polymers property of the MOFs makes the proposed nd-MSPE based on the partitioning of PAHs and thus excludes the competitive adsorption of coexisting substances. The developed nd-MSPE approach provides low detection limits (0.08-0.82 ng L-1), wide linear range (1-1000 ng L-1) and high precision (relative standard deviations (RSDs) (3.3-4.8%) in determining Cfree of PAHs. The measured Cfree of PAHs in environmental waters are in good agreement with that of verified method. Given the large diversity in structure and pore size of MOFs, various magnetic MOFs can be fabricated for task-specific nd-MSPE of analytes, presenting a prospective strategy for high-efficiency measuring Cfree of contaminants in environments.


Assuntos
Nanopartículas de Magnetita/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Adsorção , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Solubilidade
17.
J Chromatogr A ; 1603: 216-230, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31277949

RESUMO

Immobilization of biomaterials developed rapidly due to the great promise in improving their stability, activity and even selectivity. In this review, the immobilization strategies of biomaterials, including physical adsorption, encapsulation, covalent attachment, cross-linking and affinity linkage, were briefly introduced. Then, the major emphasis was focused on the reported various types of immobilized biomaterials, including proteins, enzymes, cell membrane and artificial membrane, living cells, carbohydrates and bacteria, used in the herbal analysis for bioactive compound screening, drug-target interaction evaluation and chiral separation. In addition, a series of carrier materials applied in biomaterials immobilization, such as magnetic nanoparticles, metal-organic frameworks, silica capillary column, cellulose filter paper, cell membrane chromatography, immobilized artificial membrane chromatography and hollow fiber, were also discussed. Perspectives on further applications of immobilized biomaterials in herbal analysis were finally presented.


Assuntos
Materiais Biocompatíveis/química , Extratos Vegetais/análise , Adsorção , Enzimas Imobilizadas/química , Membranas Artificiais , Estruturas Metalorgânicas/química
18.
Environ Pollut ; 253: 616-624, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330353

RESUMO

The development of high-efficiency adsorbents and the exploration of their adsorption mechanisms are major challenges in environmental remediation. Herein, MIL-100 was prepared, characterized, and utilized for the adsorptive removal of diclofenac sodium (DCF) from aqueous solutions. A high monolayer adsorption capacity of 773 mg g-1 was recorded. The adsorption mechanism was proposed based on different contributions of two types of pore structure of MIL-100 to the adsorption of DCF from aqueous solutions according to the experimental results and theoretical calculation. During adsorption process, DCF (5.2 × 7.4 × 10.3 Å) diffused through the free area of hexagonal pores (8.6 × 8.6 Å) into the cages of MIL-100, whilst it was adsorbed by the pentagonal pores (4.8 × 5.8 Å) preferentially. Internal mass transfer resistance, which was identified as one of the dominant rate-limiting steps by the mass transfer resistance kinetic models based on the Sips model, will be derived from the diffusion process, which was affected by the size-sieving effect of the pore structure of MIL-100. The successful diffusion of DCF into the interior of MIL-100 and the stable configuration between MIL-100 and DCF accounted for the high adsorption capacity. The capture of DCF into MIL-100 also resulted in the pore size distribution variation of adsorbent, which provided vital experimental evidence for the proposed mechanism. This study may offer deeper insights into other pollutants removal by metal-organic frameworks type adsorbents.


Assuntos
Diclofenaco/química , Estruturas Metalorgânicas/química , Poluentes Químicos da Água/química , Adsorção , Difusão , Cinética , Água , Purificação da Água/métodos
19.
J Chromatogr A ; 1603: 92-101, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31280943

RESUMO

In this study, three kinds of Zeolite imidazolate framework-8 (ZIF-8), synthesized by solvothermal, stirring and ball-milling method, were fabricated on the stainless steel wire via sol-gel technique. These fibers were used as solid phase microextraction (SPME) coating materials and applied for analyzing 16 polycyclic aromatic hydrocarbons (PAHs) and 11 nitro polycyclic aromatic hydrocarbons (NPAHs) in environmental water samples by gas chromatography-tandem mass spectrometry (GC-MS). The optimal pH, ionic strength, extraction time, extraction temperature, desorption temperature and desorption time were 6.0, without salt addition, 45 min, 35 °C, 260 °C and 5 min, respectively. The extraction mechanism of the ZIF-8 fiber might be the hydrophobicity, molecular penetration and π-π stacking interactions. Under the optimized conditions, the as-proposed fiber provides a wide linearity range from 10 to 20,000 ng L-1 and a low detection limit of 0.3-27.0 ng L-1 for PAHs and NPAHs analysis. The single fiber and fiber to fiber relative standard deviations were observed in the range of 3.0%-13.9% and 3.5%-12.3%, respectively. The method shows great potential in environmental analysis field.


Assuntos
Estruturas Metalorgânicas/química , Compostos de Nitrogênio/isolamento & purificação , Transição de Fase , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Concentração de Íons de Hidrogênio , Limite de Detecção , Concentração Osmolar , Hidrocarbonetos Policíclicos Aromáticos/análise , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Aço Inoxidável/química , Temperatura Ambiente , Fatores de Tempo , Poluentes Químicos da Água/análise , Difração de Raios X
20.
Anal Bioanal Chem ; 411(23): 5963-5973, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300859

RESUMO

A microscale highly fluorescent Eu metal-organic framework (Eu-MOF) was synthesized with terephthalic acid and 1H-1,2,4-triazole-3,5-diamine by one-pot hydrothermal method. And it was characterized by scanning electron microscope, Fourier transform infrared spectroscopy, powder X-ray diffraction, fluorescence spectroscopy, thermogravimetric analysis, and energy dispersive X-ray mapping. The prepared Eu-MOF has high quantum yield of 30.99%, excellent water dispersibility, good fluorescence stability, and favorable thermal stability. Based on the distinctly different fluorescence responses of different emission, the prepared Eu-MOF was used as dual-mode visual sensor for the sensitive detection of berberine hydrochloride and tetracycline. The limits of detection are 78 nM and 17 nM, respectively. The sensing mechanism was also discussed. Moreover, a filter paper sensor has been designed for sensing tetracycline with a notable fluorescence color change from blue to red. The prepared Eu-MOF is promising to be developed as a multi-mode luminescent sensor for visual detection in biochemical analysis. Graphical abstract Illustration of the synthesis of Eu-MOF and its sensing applications for berberine hydrochloride and tetracycline.


Assuntos
Antibacterianos/análise , Berberina/análise , Európio/química , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Tetraciclinas/análise , Poluentes Químicos da Água/análise , Antibacterianos/sangue , Antibacterianos/urina , Berberina/sangue , Berberina/urina , Humanos , Limite de Detecção , Rios/química , Espectrometria de Fluorescência/métodos , Comprimidos , Tetraciclinas/sangue , Tetraciclinas/urina , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/urina
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