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1.
Inorg Chem ; 59(2): 1323-1331, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31920084

RESUMO

We first design and synthesize a dendritic aromatic 6-carboxyl linker (H6TDCPB), which is successfully assembled with Cd(II) ion to construct a porous metal-organic framework with a raw Cd6 cluster, {[Cd3(TDCPB)·2DMAc]·DMAc·4H2O}n (namely, complex 1). More interestingly, six adjacent linkers are packed together by π-π-stacking interactions to form an amazing six-molecule accumulation in the crystal structure. By virtue of high stability and luminescent properties, the as-synthesized sample not merely owns an excellent detectable ability but also possesses an outstanding selectivity for nitrofurans with remarkable recursitivity.


Assuntos
Antibacterianos/análise , Corantes Fluorescentes/química , Medições Luminescentes , Estruturas Metalorgânicas/química , Corantes Fluorescentes/síntese química , Estruturas Metalorgânicas/síntese química , Estrutura Molecular
2.
J Photochem Photobiol B ; 203: 111774, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31931386

RESUMO

Zeolitic imidazole framework (ZIF) is an emerging class of metal organic frameworks exhibiting unique features such as crystalline nature with tunable pore size, large surface area and biocompatible nature. Exceptional thermal and chemical stabilities of ZIF-L make it a suitable candidate for biomedical applications. The present study has focused on the single step fabrication of catechin encapsulated ZIF-L and evaluation of its antibiofilm efficiency, larvicidal activity and dye degradation ability. The as- prepared CA@ZIF-L nanocomposite was characterized by spectroscopic and microscopic techniques. The results revealed that the CA@ZIF-L showed significant toxicity against mosquito larvae in a dose dependent manner with the IC50 63.43±1.25 µg/mL. CA@ZIF-L showed dose dependent reduction of biofilm formation in both ATCC and clinical MRSA strains. In addition, CA@ZIF-L exhibited excellent photocatalytic activity with around 92% degradation of methylene blue under direct sunlight. Overall, the present work highlights the possibility of employing the multifunctional CA@ZIF-L nanocomposite as a suitable material for biomedical and photocatalytic applications.


Assuntos
Biofilmes/efeitos dos fármacos , Catequina/química , Estruturas Metalorgânicas/química , Nanocompostos/toxicidade , Zeolitas/química , Animais , Catálise , Culicidae/efeitos dos fármacos , Culicidae/crescimento & desenvolvimento , Imidazóis/química , Larva/efeitos dos fármacos , Luz , Staphylococcus aureus Resistente à Meticilina/fisiologia , Azul de Metileno/química , Nanocompostos/química , Tamanho da Partícula , Fotólise/efeitos da radiação
3.
Top Curr Chem (Cham) ; 378(1): 11, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31903506

RESUMO

The dramatic increase in atmospheric carbon dioxide (CO2) concentrations has attracted human attention and many strategies about converting CO2 into high-value chemicals have been put forward. Metal-organic frameworks (MOFs), as a class of versatile materials, have been widely used in CO2 capture and chemical conversion, due to their unique porosity, multiple active centers and good stability and recyclability. Herein, we focused on the processes of chemical conversion of CO2 by MOFs-based catalysts, including the coupling reactions of epoxides, aziridines or alkyne molecules, CO2 hydrogenation, and other CO2 conversion reactions. The synthesized methods and high catalytic activity of MOFs-based materials were also analyzed systematically. Finally, a brief perspective on feasible strategies is presented to improve the catalytic activity of novel MOFs-based materials and explore the new CO2 conversion reactions.


Assuntos
Dióxido de Carbono/química , Estruturas Metalorgânicas/química , Alcenos/química , Aminas/química , Aziridinas/química , Catálise , Compostos de Epóxi/química , Hidrogenação , Líquidos Iônicos/química
4.
Top Curr Chem (Cham) ; 378(1): 14, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31933069

RESUMO

Classical molecular simulations can provide significant insights into the gas adsorption mechanisms and binding sites in various metal-organic frameworks (MOFs). These simulations involve assessing the interactions between the MOF and an adsorbate molecule by calculating the potential energy of the MOF-adsorbate system using a functional form that generally includes nonbonded interaction terms, such as the repulsion/dispersion and permanent electrostatic energies. Grand canonical Monte Carlo (GCMC) is the most widely used classical method that is carried out to simulate gas adsorption and separation in MOFs and identify the favorable adsorbate binding sites. In this review, we provide an overview of the GCMC methods that are normally utilized to perform these simulations. We also describe how a typical force field is developed for the MOF, which is required to compute the classical potential energy of the system. Furthermore, we highlight some of the common analysis techniques that have been used to determine the locations of the preferential binding sites in these materials. We also review some of the early classical molecular simulation studies that have contributed to our working understanding of the gas adsorption mechanisms in MOFs. Finally, we show that the implementation of classical polarization for simulations in MOFs can be necessary for the accurate modeling of an adsorbate in these materials, particularly those that contain open-metal sites. In general, molecular simulations can provide a great complement to experimental studies by helping to rationalize the favorable MOF-adsorbate interactions and the mechanism of gas adsorption.


Assuntos
Gases/isolamento & purificação , Estruturas Metalorgânicas/química , Adsorção , Dióxido de Carbono/isolamento & purificação , Simulação por Computador , Hidrogênio/isolamento & purificação , Modelos Químicos , Modelos Moleculares , Método de Monte Carlo , Eletricidade Estática , Termodinâmica
5.
Chem Soc Rev ; 49(3): 708-735, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31993598

RESUMO

Covalent organic frameworks (COFs) are an emerging class of crystalline porous polymers with highly tuneable structures and functionalities. COFs have been proposed as ideal materials for applications in the energy-intensive field of molecular separation due to their notable intrinsic features such as low density, exceptional stability, high surface area, and readily adjustable pore size and chemical environment. This review attempts to highlight the key advancements made in the synthesis of COFs for diverse separation applications such as water treatment or the separation of gas mixtures and organic molecules, including chiral and isomeric compounds. Methods proposed for the fabrication of COF-based columns and continuous membranes for practical applications are also discussed in detail. Finally, a perspective regarding the remaining challenges and future directions for COF research in the field of separation has also been presented.


Assuntos
Estruturas Metalorgânicas/química , Gases/isolamento & purificação , Isomerismo , Estrutura Molecular , Compostos Orgânicos/isolamento & purificação , Porosidade , Relação Estrutura-Atividade , Propriedades de Superfície , Purificação da Água/métodos
6.
Chem Commun (Camb) ; 56(9): 1413-1416, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31912820

RESUMO

A novel ratiometric surface-enhanced Raman scattering (SERS) biosensor was constructed based on stimuli-responsive DNA functionalized metal organic frameworks (MOFs) for detection of adenosine triphosphate (ATP). As a result, the detection range of ATP was 1 nM to 200 nM with a detection limit of 0.4 nM. The ratiometric SERS biosensor strategy offers a lower detection limit and exhibits a more enhanced performance than the typical SERS detection based on single signal response, which may have potential for detection of other biomolecules or metal ions.


Assuntos
Trifosfato de Adenosina/química , Técnicas Biossensoriais , DNA/química , Estruturas Metalorgânicas/química , Análise Espectral Raman , Propriedades de Superfície
7.
Chemosphere ; 241: 125021, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683448

RESUMO

The magnetic composite CoFe2O4/ZIF-8 based on metal organic framework (MOF) with high specific surface area and high activity was synthesized by solvothermal method. The prepared catalysts were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), vibration sample magnetometer (VSM) and N2 adsorption-desorption isotherms, respectively. After characterization, CoFe2O4/ZIF-8 was applied to heterogeneous activation of peroxymonosulfate (PMS) for degrading methylene blue (MB). The result showed that the 0.075-CoFe2O4/ZIF-8 sample had the excellent catalytic activity. After catalytic reaction for 60 min, the degradation efficiency of MB (20 mg/L) reached about 97.9% at room temperature of 20 °C. The quenching experiment and electron paramagnetic resonance (EPR) analysis indicated that SO4- and OH radicals were the main active species in MB degradation. Meanwhile, the possible MB degradation mechanism was proposed. After four catalytic cycles, the degradation efficiency of MB has not been greatly reduced, indicating the practical application potential of CoFe2O4/ZIF-8 in water pollution cleanup.


Assuntos
Cobalto/química , Corantes/química , Compostos Férricos/química , Estruturas Metalorgânicas/química , Peróxidos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Catálise , Compostos Férricos/síntese química , Magnetismo , Azul de Metileno/química
8.
Chemphyschem ; 21(1): 32-35, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31693262

RESUMO

Understanding the factors that affect self-diffusion in isoreticular and multivariate (MTV) MOFs is key to their application in drug delivery, separations, and heterogeneous catalysis. Here, we measure the apparent self-diffusion of solvents saturated within the pores of large single crystals of MOF-5, IRMOF-3 (amino-functionalized MOF-5), and 17 MTV-MOF-5/IRMOF-3 materials at various mole fractions. We find that the apparent self-diffusion coefficient of N,N-dimethylformamide (DMF) may be tuned linearly between the diffusion coefficients of MOF-5 and IRMOF-3 as a function of the linker mole fraction. We compare a series of solvents at saturation in MOF-5 and IRMOF-3 to elucidate the mechanism by which the linker amino groups tune molecular diffusion. The ratio of the self-diffusion coefficients for solvents in MOF-5 to those in IRMOF-3 is similar across all solvents tested, regardless of solvent polarity. We conclude that average pore aperture, not solvent-linker chemical interactions, is the primary factor responsible for the different diffusion dynamics upon introduction of an amino group to the linker.


Assuntos
Difusão , Estruturas Metalorgânicas/química , Dimetilformamida/química , Modelos Moleculares , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
9.
Chemosphere ; 242: 125144, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31669994

RESUMO

Currently, many kinds of organic pollutants in air and water have a negative impact on humans and the environment. Notably, as a type of new functional materials, metal-organic frameworks (MOFs) with well-ordered porous structures and numerous active sites have been proven to be ideal photocatalysts for the degradation of organic pollutants. In the past few years, many encouraging achievements have been made in the research field of MOFs for photocatalysis. And a large number of functionalized MOFs have been constructed to improve photocatalytic activity. In this review, recent progress in the photocatalytic degradation of organic pollutants in both air and water using functionalized MOFs are summarized in detail. The focus is on photocatalytic mechanisms and some strategies employed to achieve higher degradation efficiency. Furthermore, the challenges and outlooks in this promising filed are also discussed. We hope this review would be useful for designing more functionalized MOFs with greater photocatalytic performance for the degradation of organic pollutants in the environment.


Assuntos
Poluentes Ambientais/química , Estruturas Metalorgânicas , Modelos Químicos , Compostos Orgânicos , Humanos , Porosidade , Água
10.
Environ Pollut ; 256: 113399, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662253

RESUMO

Achieving large pore size, high catalytic performance with stable structure is critical for metal-organic frameworks (MOFs) to have more hopeful prospects in catalytic applications. Herein, we had reported a method to synthesize highly reactive yet stable defective iron-based Metal organic frameworks by using different monocarboxylic acids with varying lengths as a modulator. The physical-chemical characterization illustrating that modulators could improve the crystallinity, enlarge pore size and enhance catalytic performance and octanoic acid (OA) was screened to be the suitable choice. The catalytic performance of catalysts was detected through persulfate (PS) activation for degrading Tetrabromobisphenol A (TBBPA). The study demonstrated that the highest degradation efficiency for 0.018 mmol L-1 TBBPA was that 97.79% in the conditions of the 1.0 g L-1 Fe(BDC)(DMF,F)-OA-30 dosage and TBBPA:PS = 200:1. In addition, there was observed that no obvious change of the crystal structure, little the leachable iron concentration in the solutions and no significant loss of catalytic activities of Fe(BDC)(DMF,F)-OA-30 after 5th cycles. The iron valence state of Fe(BDC)(DMF,F)-OA-30 before and after degradation and electrochemical properties reveal that the partial substitution of organic ligands by octanoic acid, when removing OA and forming defects by heat and vacuum treatment to generate coordinatively unsaturated metal sites and accelerate the original transmission of electronic, leading to enhance the activity of persulfate activation for efficient removal TBBPA.


Assuntos
Modelos Químicos , Bifenil Polibromatos/química , Catálise , Ferro/química , Estruturas Metalorgânicas
11.
Anal Bioanal Chem ; 412(2): 355-364, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31760446

RESUMO

An innovative electrochemical sensor was proposed for simultaneous determination of mycophenolate mofetil (Mph) and tacrolimus (TAC) for the first time. A novel sensor based on electro-polymerization of multi-walled carbon nanotubes (MWCNTs) and a novel Cu-1N-allyl-2-(2,5-dimethoxyphenyl)-4,5-diphenyl-1H-imidazole metal organic framework (Cu-ADPPI MOF) on disposable pencil graphite electrode (dPGE). Many techniques were used to characterize the electrochemical activity and surface structure of the fabricated sensor. The proposed sensor exhibited good catalytic performance towards Mph and TAC oxidation due to the synergistic effect. Under optimal conditions, the proposed sensor has achieved a linear range of 0.85-155 × 10-8 M and 1.1-170.0 × 10-8 M with LODs of 0.28 × 10-8 M and 0.36 × 10-8 M for Mph and TAC, respectively. The designated sensor showed good reproducibility, repeatability, stability, and selectivity for the determination of Mph and TAC. Moreover, the simultaneous determination of Mph and TAC in different human biological fluids was carried out with acceptable results. As a result, the proposed sensor opens a new venue for the use of electro-polymerized MOFs in combination with other conductive materials such as MWCNTs for electrochemical sensing of different analytes with the desired sensitivity and selectivity. Graphical abstract Construction of disposable graphite electrode, based on electro-deposition of multilayer films of multi-walled carbon nanotubes and a new generation of Cu-MOFs, for simultaneous analysis of tacrolimus and mycophenolate mofetil for the first time.


Assuntos
Eletrodos , Grafite/química , Imunossupressores/análise , Ácido Micofenólico/análise , Tacrolimo/análise , Humanos , Imunossupressores/sangue , Imunossupressores/urina , Limite de Detecção , Estruturas Metalorgânicas/química , Ácido Micofenólico/sangue , Ácido Micofenólico/urina , Nanoestruturas/química , Polimerização , Reprodutibilidade dos Testes , Tacrolimo/sangue , Tacrolimo/urina
12.
Chem Asian J ; 15(1): 182-190, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31769211

RESUMO

Metal-organic frameworks (MOFs) as new classes of proton-conducting materials have been highlighted in recent years. Nevertheless, the exploration of proton-conducting MOFs as formic acid sensors is extremely lacking. Herein, we prepared two highly stable 3D isostructural lanthanide(III) MOFs, {(M(µ3 -HPhIDC)(µ2 -C2 O4 )0.5 (H2 O))⋅2 H2 O}n (M=Tb (ZZU-1); Eu (ZZU-2)) (H3 PhIDC=2-phenyl-1H-imidazole-4,5-dicarboxylic acid), in which the coordinated and uncoordinated water molecules and uncoordinated imidazole N atoms play decisive roles for the high-performance proton conduction and recognition ability for formic acid. Both ZZU-1 and ZZU-2 show temperature- and humidity-dependent proton-conducting characteristics with high conductivities of 8.95×10-4 and 4.63×10-4  S cm-1 at 98 % RH and 100 °C, respectively. Importantly, the impedance values of the two MOF-based sensors decrease upon exposure to formic acid vapor generated from formic aqueous solutions at 25 °C with good reproducibility. By comparing the changes of impedance values, we can indirectly determine the concentration of HCOOH in aqueous solution. The results showed that the lowest detectable concentrations of formic acid aqueous solutions are 1.2×10-2  mol L-1 by ZZU-1 and 2.0×10-2  mol L-1 by ZZU-2. Furthermore, the two sensors can distinguish formic acid vapor from interfering vapors including MeOH, N-hexane, benzene, toluene, EtOH, acetone, acetic acid and butane. Our research provides a new platform of proton-conductive MOFs-based sensors for detecting formic acid.


Assuntos
Formiatos/análise , Elementos da Série dos Lantanídeos/química , Estruturas Metalorgânicas/química , Prótons , Umidade , Tamanho da Partícula , Temperatura Ambiente
13.
Chem Commun (Camb) ; 56(4): 519-522, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31825411

RESUMO

For the first time, a facile solvothermal method to synthesize covalent organic frameworks (COFs) with a nanosized structure and bright fluorescence was reported to monitor drug loading with the naked eye and realize responsive release.


Assuntos
Antibióticos Antineoplásicos/química , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Corantes Fluorescentes/síntese química , Estruturas Metalorgânicas/síntese química , Estrutura Molecular , Tamanho da Partícula
14.
Food Chem ; 310: 125820, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31810725

RESUMO

In the present study, a sensitive label-free electrochemical aptasensor is introduced to measure aflatoxin M1 (AFM1) by using platinum nanoparticles (PtNPs) decorated on a glassy carbon electrode (GCE) modified with Fe-based metal-organic frameworks, MIL-101(Fe). The MIL-101(Fe) and the PtNP/MIL-101(Fe) are synthesized and characterized by Fourier transform infrared spectroscopy, X-ray diffraction, UV-Visible spectroscopy, and field-emission scanning electron microscopy. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) are done to monitor the fabrication processes of the aptasensor. In optimum conditions, the linear calibration range of 1.0 × 10-2 to 80.0 ng mL-1 and the detection limit of 2.0 × 10-3 ng mL-1 are obtained to measure AFM1 concentration using the EIS method. Finally, the fabricated aptasensor is successfully applied to measure AFM1 concentration in powder and pasteurized milk samples.


Assuntos
Aflatoxina M1/análise , Técnicas Eletroquímicas/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Leite/química , Animais , Aptâmeros de Peptídeos/química , Carbono , Espectroscopia Dielétrica/instrumentação , Espectroscopia Dielétrica/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Análise de Alimentos/instrumentação , Ferro/química , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Pasteurização , Platina/química , Pós/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Chem Commun (Camb) ; 56(4): 659-662, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31840150

RESUMO

Co-based metal organic frameworks (ZIF-67), working as an oxidase-mimicking nanozyme, can simultaneously catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) and Amplex red, exhibiting a high catalytic activity. For Amplex red, two consecutive redox reactions are reported, which is specifically applied for fluorescence "turn-on" detection of biothiols.


Assuntos
Cobalto/química , Fluorescência , Estruturas Metalorgânicas/química , Nanopartículas/química , Oxirredutases/química , Compostos de Sulfidrila/análise , Catálise , Cobalto/metabolismo , Estruturas Metalorgânicas/metabolismo , Estrutura Molecular , Nanopartículas/metabolismo , Oxirredução , Oxirredutases/metabolismo , Tamanho da Partícula , Compostos de Sulfidrila/metabolismo , Propriedades de Superfície
16.
Chemosphere ; 241: 125002, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31590027

RESUMO

Iron and copper bimetallic MOF material (FexCu1-x(BDC)) as a novel Fenton-like catalyst was prepared by a simple solvothermal method, and its performances were evaluated in the catalytic degradation of sulfamethoxazole (SMX) in the presence of hydrogen peroxide. The results indicated that the FexCu1-x(BDC)/H2O2 system was highly effective for SMX degradation over a wide pH range (4.0-8.6). At initial solution pH of 5.6, the bimetallic Fe0.75Cu0.25(BDC) catalyst exhibited a 100% SMX (20 mg L-1) removal within 120 min, which was superior to the SMX removal efficiency over monometallic Fe(BDC) and Cu(BDC) catalysts. Combined with the physical-chemical characterization, the synergistic effect between Fe and Cu species were responsible for the efficient catalytic activity. Moreover, the Fe0.75Cu0.25(BDC) catalyst showed good reusability for SMX degradation. The possible reaction mechanism in FexCu1-x(BDC)/H2O2 system was also tentatively proposed. This work has not only suggested the potential of bimetallic FexCu1-x(BDC) catalysts in Fenton-like treatment of antibiotics, but also provided useful information to develop MOF-based catalysts for efficient environmental remediation.


Assuntos
Cobre/química , Recuperação e Remediação Ambiental/métodos , Ferro/química , Estruturas Metalorgânicas/química , Sulfametoxazol/química , Catálise , Peróxido de Hidrogênio/química , Estruturas Metalorgânicas/farmacologia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
17.
Biomed Chromatogr ; 34(1): e4725, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31755114

RESUMO

For the analysis of methylhippuric acids (MHAs) in human urine samples, in this study, a new method based on the metal-organic framework (MOF) of MIL-53-NH2 (Al) in microextraction by packed sorbent (MEPS) was developed. The synthesis of MIL-53-NH2 (Al) was characterized by Fourier transform infrared spectra, field emission-scanning electron microscopy and X-ray diffraction. Response surface methodology was used to investigate the influences of several parameters including type and volume of elution, type of conditional solvent, sample volume and extraction cycle on MEPS efficiency. The results showed good recoveries (>94%) and excellent extraction efficiencies (>96%) at three different concentrations of 50, 500 and 1500 µg ml-1 (as low, mid and high concentrations, respectively) of MHA isomers. Calibration curves of MHAs were linear over the concentration range of 1-1500 µg ml-1 , with high correlation coefficients (r ≥ 0.998). The reproducibility of the proposed MIL-53-MEPS for determination of three isomers of MHA was found to be in the range of 3.5-11.1%. After optimization of the proposed technique, it was used to analyze MHAs in urine samples of workers exposed to xylenes in a petrochemical plant in Asalouyah, Iran. The results indicated that the MOF-MEPS method was selective, sensitive, rapid and efficient for the extraction of urinary MHAs. The technique is also environmentally friendly and inexpensive, and the MOF sorbent is reusable.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hipuratos/urina , Estruturas Metalorgânicas/química , Microextração em Fase Sólida/métodos , Desenho de Equipamento , Humanos , Limite de Detecção , Modelos Lineares , Exposição Ocupacional/análise , Reprodutibilidade dos Testes , Microextração em Fase Sólida/instrumentação
18.
J Environ Manage ; 255: 109874, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783210

RESUMO

This review paper focuses on various gas processing technologies and materials that efficiently capture trace levels of carbon dioxide (CO2). Fundamental separation mechanisms such as absorption, adsorption, and distillation technology are presented. Liquid amine-based carbon capture (C-capture) technologies have been in existence for over half a century, however, liquid amine capture relies upon chemical reactions and is energy-intensive. Liquid amines are thus not economically viable for broad deployment and offer little room for innovation. Innovative C-capture technologies must improve both the environmental footprint and cost-effectiveness. As a promising alternative, physisorbents have many advantages including considerably lower regeneration energy. Generally, existing classes of physisorbent materials, such as metal-organic frameworks (MOFs) and zeolites are selective toward C-capture. However, their selectivity is currently not high enough to remove trace levels (e.g., ~1%) of CO2 from various natural gas process streams. This review summarizes the current advancements in physisorbent materials for CO2 capture. Here, key performance parameters needed to select the most suitable candidate are highlighted. Furthermore, this review discusses the scope for the development of better performing CO2 selective physisorbents from both environmental and economic perspectives. In addition, hybrid ultra microporous materials (HUMs), characterized mainly by ultra-micro pores (<0.7 nm), are discussed in reference to C-capture. Various characteristics of HUMs result in high selectivity and applicability in difficult separations such as the gas sweetening and C-capture from complex humid mixed gas streams.


Assuntos
Estruturas Metalorgânicas , Zeolitas , Adsorção , Aminas , Dióxido de Carbono
19.
Chemistry ; 26(7): 1668-1675, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31814171

RESUMO

Despite drug delivery nanoplatforms receiving extensive attention, development of a simple, effective, and multifunctional theranostics nanoplatform still remains a challenge. Herein, a versatile nanoplatform based on a zirconium framework (UiO-66-N3 ) was synthesized, which demonstrated a combined photodynamic therapy (PDT), photothermal therapy (PTT), and chemotherapy (CT) for cancer treatment. A RuII polypyridyl alkyne complex (Ra) as a photosensitizer was modified into a nanoplatform by click reactions for the first time. When exposed to suitable light irradiation, the as-prepared multifunctional nanoplatform (UiO-Ra-DOX-CuS) not only demonstrated efficient 1 O2 generation, but also exhibited excellent photothermal conversion ability. In particular, the nanotherapeutic agent presented a dual-stimuli response; either acidic environment or NIR laser irradiation would trigger the drug release. The synergetic efficacy of UiO-Ra-DOX-CuS combined PDT, PTT, and CT, which was evaluated by cell experiments. Moreover, the design could promote the development of RuII polypyridyl alkyne complexes based multifunctional nanoparticles and multimodal cancer treatment.


Assuntos
Alquinos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Compostos de Rutênio/química , Terapia Combinada , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Quimioterapia Combinada , Humanos , Estruturas Metalorgânicas , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Nanomedicina Teranóstica
20.
Chem Commun (Camb) ; 56(4): 591-594, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31830154

RESUMO

The interaction between an aMOC and miRNA/DNA is studied and the use of a signal probe DNA (spDNA)@aMOC complex as an effective amplifier in a QCM sensor to detect miRNA is developed. The signal can be significantly enhanced, which leads to improved performance when detecting and distinguishing miRNAs.


Assuntos
Técnicas Biossensoriais , DNA/química , Estruturas Metalorgânicas/química , MicroRNAs/química , Técnicas de Microbalança de Cristal de Quartzo , Estrutura Molecular , Tamanho da Partícula , Porosidade , Propriedades de Superfície
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