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1.
Molecules ; 26(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669135

RESUMO

Thanks to their well-defined molecular sieving and stability, zeolites have been proposed in selective membrane separations, such as gas separation and pervaporation. For instance, the incorporation of zeolites into polymer phases to generate composite (or mixed matrix) membranes revealed important advances in pervaporation. Therefore, the goal of this review is to compile and elucidate the latest advances (over the last 2-3 years) of zeolite applications in pervaporation membranes either combining zeolites or polymers. Here, particular emphasis has been focused on relevant insights and findings in using zeolites in pervaporative azeotropic separations and specific aided applications, together with novel concepts of membranes. A brief background of the pervaporation process is also given. According to the findings of this review, we provide future perspectives and recommendations for new researchers in the field.


Assuntos
Zeolitas/isolamento & purificação , Solventes/química , Volatilização , Zeolitas/química
2.
Molecules ; 26(4)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673249

RESUMO

The low cost ß-zeolite and ethylenediamine modified ß-zeolite (EDA@ß-zeolite) were prepared by self-assembly method and used for Cu(II) removal from contaminated aqueous solution. Removal ability of ß-zeolite toward Cu(II) was greatly improved after ethylenediamine (EDA) modification, the removal performance was greatly affected by environmental conditions. XPS results illustrated that the amide group played important role in the removal process by forming complexes with Cu(II). The EDA@ß-zeolite showed desirable recycling ability. The finding herein suggested that the proposed composite is a promising and suitable candidate for the removal of Cu(II) from contaminated natural wastewater and aquifer.


Assuntos
Cobre/isolamento & purificação , Etilenodiaminas/química , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/química , Adsorção , Cobre/toxicidade , Humanos , Água/química , Poluentes Químicos da Água/toxicidade
3.
Food Chem ; 349: 129127, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33561794

RESUMO

Metal-organic structures (MOFs) have been designed for a wide range of applications due to their high porosity, large surface area, and flexibility. For the first time in this work, the successful immobilization of α-amylase is confirmed by the use of ZIF-8 as easy and good support. The morphology, functional groups, and chemical composition of the support and immobilized α-amylase were tested using different methods such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA). The enzymatic activities of the immobilized olibanum-bovine serum albumin@zeolitic imidazolate frameworks nanocomposite (OLB/BSA@ZIF-8)-α-amylase were compared with the free one. The pH and thermal stability of the OLB/BSA@ZIF-8-α-amylase were significantly enhanced compared to the free enzyme. The OLB/BSA@ZIF-8-α-amylase displayed excellent long-term storage stability, which could protect more than 90% of the initial activity for 8 weeks. Besides, the OLB/BSA@ZIF-8-α-amylase had high reusability, which showed a high degree of activity (more than 81%) after 20 cycles. This is the first study that uses OLB/BSA@ZIF-8 nanocomposite as immobilizing support for the immobilization of α-amylase. Improved catalytic efficiency (Vmax/Km) values, reusability, and storage stability of immobilized α-amylase can make it suitable in industrial and biotechnological applications.


Assuntos
Enzimas Imobilizadas/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Soroalbumina Bovina/química , alfa-Amilases/química , Animais , Biocatálise , Biotecnologia , Bovinos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Porosidade , Zeolitas/química , alfa-Amilases/metabolismo
4.
ACS Appl Mater Interfaces ; 13(7): 8718-8726, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33569946

RESUMO

In this work, a red emission fluorescent probe CBZ-BOD@zeolitic imidazolate framework-8 (ZIF-8) was fabricated based on metal-organic frameworks (MOFs) for detecting carboxylesterase 1 (CES1). The small molecule probe CBZ-BOD was first synthesized and then used to prepare the functionalized MOF material. ZIF-8 was chosen as an encapsulation shell to improve the detection properties of CBZ-BOD. Using this unique porous materials, ultrasensitive quantification of CES1 and chlorpyrifos was successfully realized. The low detection limit and high fluorescence quantum yield were calculated as 1.15 ng/mL and 0.65 for CBZ-BOD@ZIF-8, respectively. CBZ-BOD@ZIF-8 has good biocompatibility and was successfully applied to monitor the activity of CES1 in living cells. A molecular docking study was used to explore the binding of CES1 and CBZ-BOD, finding that CES1 can bind with the probe before and after hydrolysis. This type of materialized probe can inspire the development of fluorescent tools for further exploration of many pathological processes.


Assuntos
Compostos de Boro/química , Hidrolases de Éster Carboxílico/análise , Clorpirifos/análise , Corantes Fluorescentes/química , Estruturas Metalorgânicas/química , Zeolitas/química , Corantes Fluorescentes/síntese química , Humanos , Estruturas Metalorgânicas/síntese química , Simulação de Acoplamento Molecular , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
5.
Ecotoxicol Environ Saf ; 210: 111862, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429321

RESUMO

Microcystin-leucine arginine (MC-LR) is a carcinogenic toxin, produced by cyanobacteria. The release of this toxin into drinking water sources can threaten public health and environmental safety. Therefore, effective MC-LR removal from water resources is necessary. In the present study, the hydrothermal method was used to synthesize a novel ternary BiVO4/TiO2/NaY-Zeolite (B/T/N-Z) nanocomposite for MC-LR degradation under visible light. FESEM, FTIR, XRD, and DRS were performed for characterizing the nanocomposite structure. Also, the Response Surface Methodology (RSM) was applied to determine the impact of catalyst dosage, pH, and contact time on the MC-LR removal. High-performance liquid chromatography was performed to measure the MC-LR concentration. Based on the results, independent parameters, including contact time, catalyst dosage, and pH, significantly affected the MC-LR removal (P < 0.05). In other words, increasing the contact time, catalyst dosage, and acidic pH had positive effects on MC-LR removal. Among these variables, the catalyst dosage, with the mean square and F-value of 1041.37 and 162.84, respectively, had the greatest effect on the MC-LR removal efficiency. Apart from the interaction between the catalyst dosage and contact time, the interaction effects of other parameters were not significant. Also, the maximum MC-LR removal efficiency was 99.88% under optimal conditions (contact time = 120 min, catalyst dosage = 1 g/L, and pH = 5). According to the results, the B/T/N-Z nanocomposite, as a novel and effective photocatalyst could be used to degrade MC-LR from polluted water.


Assuntos
Luz , Toxinas Marinhas/química , Microcistinas/química , Nanocompostos/efeitos da radiação , Titânio/efeitos da radiação , Vanadatos/efeitos da radiação , Poluentes Químicos da Água/química , Ítrio/efeitos da radiação , Zeolitas/efeitos da radiação , Bismuto/química , Catálise , Nanocompostos/química , Processos Fotoquímicos , Titânio/química , Vanadatos/química , Purificação da Água/métodos , Ítrio/química , Zeolitas/química
6.
J Chromatogr A ; 1637: 461866, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33422798

RESUMO

New material zeolitic imidazolate framework-4, 5-imidazoledicarboxylic acid (ZIF-IMD) located on the pore surface of porous layer open-tubular (PLOT) column previously functionalized with N-(3-aminopropyl)-imidazole have been prepared via a layer-by-layer self-assembly strategy. This new ZIF-IMD coating hybrids are used as solid-phase carriers for chiral selector pepsin immobilization. The ZIF-IMD material was characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscope and X-ray diffraction. The synthesized pepsin@ZIF-IMD@POLT column achieved the baseline separation of hydroxychloroquine (HCQ), chloroquine (CHQ) and hydroxyzine (HXY) (the resolution of HCQ: 2.19; CHQ: 1.84; HXY: 1.53). Compared with the pepsin@PLOT column (without ZIF-IMD material), the chiral separation capability of the pepsin@ZIF-IMD@POLT column can be remarkably improved. Several key parameters including concentration of chiral selector, buffer pH, applied voltage and buffer concentration were systematically evaluated to provide the optimal enantioseparation condition. The relative standard deviations (RSDs) of intra-day, inter-day, column-to-column and inter-batch of migration time and Rs of the HCQ were evaluated in detail, respectively (RSD < 7.21%). Additionally, the potential mechanism of increased resolution was discussed in the article.


Assuntos
Eletrocromatografia Capilar/métodos , Imidazóis/química , Pepsina A/química , Preparações Farmacêuticas/química , Preparações Farmacêuticas/isolamento & purificação , Zeolitas/química , Tampões (Química) , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Porosidade , Reprodutibilidade dos Testes , Estereoisomerismo
7.
Ecotoxicol Environ Saf ; 209: 111839, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385682

RESUMO

Potato is considered a nitrogen (N) intensive plant with a low N use efficiency (NUE). The current study introduced an excellent approach by combining dicyandiamide (DCD), moringa seed oil (MSO), or zeolite (ZE), with N fertilizer for maximizing potato tuber yields and NUE as well as minimizing tubers nitrate (NO3-) accumulation. The impact of these materials on soil N availability and gaseous emissions (NH3, and N2O) was investigated under incubation conditions. A 2-year field experiment were carried out with seven treatments [without N (control), N fertilizer (350 kg N-urea ha-1 as a recommended dose; UreaRD), 75% of N recommended dose with DCD (Urea75%RD+DCD), Urea75%RD with 2% MSO (Urea75%RD+MSO2%), Urea75%RD with 4% MSO (Urea75%RD+MSO4%), Urea75%RD with 0.5 Mg ZE ha-1 (Urea75%RD+ZER1), and Urea75%RD with 1.0 Mg ZE ha-1 (Urea 75%RD+ZER2)]. We also conducted a 40-days incubation trial with the same treatments; however, urea was added at the rate of 200 mg N kg-1 soil for all treatments, excluding the control. The addition of DCD, MSO, and ZE with urea under incubation conditions delayed the nitrification process, thereby causing a rise in NH4+-N content and a decrease in NO3--N content. Ammonia-oxidizing bacteria (AOB) was inhibited (p ≤ 0.01) in treatments Urea+DCD, Urea+MSO4%, and Urea+ZER2. The highest NUE indexes were recorded in treatment Urea75%RD+DCD. The highest NO3- accumulation (567 mg NO3- kg-1) in potato tubers was recorded in treatment UreaRD. Whilest, the lowest NO3- content (81 mg NO3- kg-1) was in treatment Urea75%RD+DCD. The lowest cumulative N2O emissions and highest cumulative NH3 volatilization were observed in the treatment Urea+DCD under incubation conditions. Our findings demonstrated that N fertilizer rate could be reduced by 25%, while the tuber yields increased with an acceptable limit of NO3- content, resulting in economical, agronomical, and environmental benefits.


Assuntos
Recuperação e Remediação Ambiental/métodos , Fertilizantes/análise , Moringa , Nitratos/metabolismo , Nitrogênio/metabolismo , Zeolitas/química , Agricultura , Amônia/análise , Betaproteobacteria , Guanidinas , Nitrificação , Nitrogênio/análise , Óxidos de Nitrogênio , Solo , Microbiologia do Solo , Solanum tuberosum , Ureia
8.
ACS Appl Mater Interfaces ; 13(5): 6034-6042, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33499584

RESUMO

MicroRNA (miRNA) represents a promising class of therapeutic nucleic acid drugs, while delivery challenges remain that impede the advancement of miRNA therapy, largely because of in vivo instability and low delivery efficiency. Herein, we discover the dual roles of metal-organic framework (MOF) nanoparticles (ZIF-8) as nanocarriers for miRNA delivery and adjuvants for chemodynamic therapy. The miR-34a-m@ZIF-8 complex demonstrated efficient cellular uptake and lysosomal stimuli-responsive miRNA release. Zn2+ triggered the generation of reactive oxygen species, which consequently induced apoptosis of tumor cells. Released miR-34a-m led to a remarkable decrease in expression of Bcl-2 at both mRNA and protein levels and enhanced cancer cell apoptosis. In vivo experiments showed high efficacy of using miR-34a-m@ZIF-8 to suppress tumor growth via synergistic gene/chemodynamic therapy in a mouse model of triple-negative breast cancer. Our work demonstrates MOFs as a promising nanoplatform for efficient synergetic gene/chemodynamic therapy.


Assuntos
Adjuvantes Farmacêuticos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/química , MicroRNAs/farmacologia , Nanopartículas/química , Adjuvantes Farmacêuticos/química , Animais , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , MicroRNAs/química , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície , Zeolitas/química , Zeolitas/farmacologia
9.
J Mater Chem B ; 9(4): 1059-1068, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33400757

RESUMO

Nitric oxide (NO) is an essential signaling molecule with a number of biological functions and holds great promise in biomedical applications. However, NO delivery technologies have been complicated due to the inherent properties of NO which include short half-life and limited transport distance in human tissues. In addition, the biofunctionality of NO is strongly dependent on its concentrations and locations where it is delivered. To achieve controlled NO delivery, many studies have focused on encapsulating NO donors into macromolecular scaffolds or using catalysts to realize in situ NO generation from NO prodrugs. Successful applications have been shown, however NO donor-loaded platforms experience the limitation of finite NO storage capacity. The present study reports the synthesis of a catalyst, copper-doped zeolitic imidazolate framework ZIF-8 (Cu2+/ZIF-8), that is designed to generate NO from naturally occurring endogenous NO donors. By tuning the copper doping percentages, we achieved controlled NO generation from S-nitrosoglutathione (GSNO) and S-nitrosocysteine (CysNO). Cu2+/ZIF-8 particles retained their catalytic potency after 5 NO generation cycles and we showed that our copper-doped ZIF-8 catalyst produced a 10-fold increased amount of NO compared with previous reports. As a proof-of-concept study, we demonstrated the ability of copper-doped ZIF-8 to disperse bacterial biofilms in the presence of GSNO.


Assuntos
Cobre/química , Estruturas Metalorgânicas/química , Óxido Nítrico/síntese química , S-Nitrosotióis/química , Estrutura Molecular , Óxido Nítrico/química , Tamanho da Partícula , Propriedades de Superfície , Zeolitas/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-33507138

RESUMO

The evaluation of the nitrification kinetics in the simultaneous presence of sulfide and organic matter using zeolite as improver was the main goal of this work. According to the sensitivity and collinearity analyses, five parameters were the most sensitive in the model, whose calibrated values were: µ max, AOB = 0.02642 ± 0.002 h-1; µ max, NOB = 0.3307 ± 0.416 h-1; K S,NOB = 1.65·10-6 ± 2.85·10-6 mgHNO2-N/L; k S2 = 0.8213 ± 0.076 and n = 0.6537 ± 0.030. A good fit between the experimental data and the model's results including the effect of zeolite on the kinetic parameters was obtained, with Theil inequality coefficient values between 0.109 and 0.007 for all the variables studied, with all of these values lower than 0.3. Thus, the model proposed is robust and can simulate the nitrification process in the presence of sulfide and organic matter when zeolite was used as improver.


Assuntos
Reatores Biológicos/microbiologia , Substâncias Húmicas/análise , Sulfetos/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zeolitas/química , Cinética , Modelos Químicos , Nitratos/análise , Nitrificação , Nitritos/análise
11.
Chemosphere ; 263: 127935, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32810774

RESUMO

Carbon dioxide (CO2) is the main contributor to global warming; therefore, research efforts aim at its capture. Membranes, in particular, zeolite membranes offer a promising approach for CO2 separation and capture. Membranes are typically characterized by their selectivity and permeance that are highly dependent on the operating conditions namely, total feed pressure and composition. Therefore, more reliable characterization parameters are required such as Maxwell- Stefan exchange diffusivities. In this work, a model based on Maxwell-Stefan equations and Extended Langmuir isotherm was developed to investigate the transport of binary mixtures of CO2 and N2 through thin silicalite-1 membranes. The exchange diffusivities, D12 and D21, of CO2 and N2 were determined at different total feed pressures and feed compositions. All gas separation tests were conducted at stage cut not exceeding 5%. The single component diffusivities of CO2 and N2 required by the model were found experimentally using the results of the respective single gas permeation tests. The results displayed that as CO2 concentration in the feed increased from 15% to 85%, the values of D12 and D21 decreased from 2.8 × 10-10 to 1.1 × 10-10 m2/s and 2.8 × 10-10 to 1.3 × 10-10 m2/s, respectively, while the N2 permeance decreased by about one order of magnitude from 2.7 × 10-7 to 2.4 × 10-8 mol/m2.s.Pa. Consequently, the exchange diffusivities showed considerably smaller dependence on the operating conditions compared to the permselectivity and permeance. Hence, they are more appropriate in describing the intrinsic transport characteristics of silicalite-1 membranes.


Assuntos
Dióxido de Carbono/química , Modelos Químicos , Zeolitas/química
12.
Food Chem ; 339: 127863, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871299

RESUMO

In this work, one kind of zeolite imidazole frameworks containing bovine serum albumin stabilized Au nanoclusters (AuNCs), ß-galactosidase (ß-Gal) and glucose oxidase (GOx) (AuNCs/ß-Gal/GOx@ZIF-8) were obtained to detect lactose. Compared with other fluorescent nano-materials, AuNCs show distinct advantages as a guest species in ZIF-8, specifically their extremely small size (<1 nm), simple synthesis, excellent biocompatibility and high stability. Furthermore, the bovine serum albumin on their surfaces can promote the formation of ZIF-8 coating; thus, AuNCs were co-encapsulated in ZIF-8 with the enzymes together. X-ray diffraction (XRD) analysis indicates the composite possesses the similar crystalline structure with pure ZIF-8. Fluorescence microscope images, Fourier transform infrared spectra and energy dispersive X-ray spectroscopy indicate the presence of AuNCs in the composite. Owing to the high local concentrations of the fluorescent probe and the quenching agent in AuNCs/ß-Gal/GOx@ZIF-8, the quenching rate was enhanced 3.4-fold that of free AuNCs and enzymes in solution.


Assuntos
Técnicas Biossensoriais/métodos , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Ouro/química , Lactose/análise , Limite de Detecção , Estruturas Metalorgânicas/química , Cápsulas , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Soroalbumina Bovina/química , Zeolitas/química
13.
Chemosphere ; 262: 127772, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32799140

RESUMO

This study utilized the freshwater amphipod (Hyalella azteca) for the indication of contamination risk levels of sediment-associated contaminants in the Erren (ER1∼ER10) and Sanye Rivers (SY1∼SY5) which were contaminated by metal scrap and smelting industries for decades. Toxicity identification evaluations involving the manipulation of pore water and whole-sediment samples were conducted to identify causative pollutants. Impacts on the aquatic environment were then evaluated in order to explore how industrial development led to contaminant accumulation in sediments and resulted in biological effects. A whole-sediment TIE indicated that the major toxicant at sampling sites ER8 and SY5 was ammonia and that its toxicity was significantly reduced by the addition of zeolite. Toxicity at sampling sites ER4 and ER9 was induced by ammonia and heavy metals (Zn, Cd, Cr, As), whereas Cr was at toxic levels at ER6. ∑PAHs was another major class of contaminants at site ER2. Metals (Zn, Ni, Pb, Cd, Cr, and As) were identified as major toxic contaminants at three sites (ER3, SY1, and SY3). The application of TIEs confirmed that a causative toxicant can be identified and that its measured toxicity correlated with its concentration. In conclusion, a TIE approach was successful in demarcating most effective contaminant groups (ammonia, heavy metals, and non-polar organic compounds) in whole-sediment cores, their porewaters and potential toxicities from a highly polluted river after remediation in southern Taiwan to an invertebrate animal model H. azteca.


Assuntos
Anfípodes/efeitos dos fármacos , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Rios/química , Poluentes Químicos da Água/toxicidade , Amônia/análise , Amônia/toxicidade , Animais , Água Doce/química , Metais Pesados/análise , Metais Pesados/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Taiwan , Clima Tropical , Poluentes Químicos da Água/análise , Zeolitas/química
14.
Chemosphere ; 262: 127932, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805662

RESUMO

Zeolite addition has been widely suggested for its ability to overcome ammonia stress occurring during anaerobic digestion. However little is known regarding the underlying mechanisms of mitigation and especially how zeolite influences the microbial structuration. The aim of this study was to bring new contributions on the effect of zeolite on the microbial community arrangement under a low ammonia stress. Replicated batch experiments were conducted. The microbial population was characterised with 16S sequencing. Methanogenic pathways were identified with methane isotopic fractionation. In presence of ammonia, zeolite mitigated the decrease of biogas production rate. Zeolite induced the development of Izimaplasmatales order and preserved Peptococcaceae family members, known as propionate degraders. Moreover methane isotopic fractionation showed that hydrogenotrophic methanogenesis was maintained in presence of zeolite under ammonia low stress. Our results put forward the benefit of zeolite to improve the bacteria-archaea syntrophy needed for propionate degradation and methane production under a low ammonia stress.


Assuntos
Alimentos , Eliminação de Resíduos , Zeolitas/química , Amônia/metabolismo , Anaerobiose , Archaea/metabolismo , Bactérias/metabolismo , Biocombustíveis , Reatores Biológicos , Metano/metabolismo , Microbiota , Propionatos/metabolismo
15.
Food Chem ; 339: 127854, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32829245

RESUMO

Gold nanoparticles (AuNPs)-based lateral flow assay (LFA) enables a rapid detection of tetracycline (TET) in food samples but suffers from low sensitivity. Herein, metal-polydopamine framework (MPF), as a label, was employed to load monoclonal antibodies (mAbs) directly as the probe in LFA for highly sensitive sensing of TET. Combining zeolitic imidazolate framework (ZIF-67) and polydopamine (PDA), a stable MPF with large size, well water-dispersible, excellent affinity and optical properties was prepared through a versatile layer-by-layer assembly (LLA) strategy. Under optimized conditions, the biosensor (MPF-LFA) exhibited a great linear relationship in the range of 0.09-6 ng/mL and a detection limit of 0.045 ng/mL for TET detection, which was over 66-fold more sensitive than traditional AuNPs based LFA. Furthermore, the MPF-LFA was successfully applied to the screening of TET in fish, chicken, milk and shrimp samples with satisfied recoveries from 91% to 114%.


Assuntos
Antibacterianos/análise , Análise de Alimentos/métodos , Ouro/química , Indóis/química , Estruturas Metalorgânicas/química , Polímeros/química , Tetraciclina/análise , Animais , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanopartículas Metálicas/química , Leite/química , Alimentos Marinhos/análise , Zeolitas/química
16.
Int J Nanomedicine ; 15: 10029-10043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335393

RESUMO

Purpose: Despite the significant advances in modeling of biomechanical aspects of cell microenvironment, it remains a major challenge to precisely mimic the physiological condition of the particular cell niche. Here, the metal-organic frameworks (MOFs) have been introduced as a feasible platform for multifactorial control of cell-substrate interaction, given the wide range of physical and mechanical properties of MOF materials and their structural flexibility. Results: In situ crystallization of zeolitic imidazolate framework-8 (ZIF-8) on the polydopamine (PDA)-modified membrane significantly raised surface energy, wettability, roughness, and stiffness of the substrate. This modulation led to an almost twofold increment in the primary attachment of dental pulp stem cells (DPSCs) compare to conventional plastic culture dishes. The findings indicate that polypropylene (PP) membrane modified by PDA/ZIF-8 coating effectively supports the growth and proliferation of DPSCs at a substantial rate. Further analysis also displayed the exaggerated multilineage differentiation of DPSCs with amplified level of autocrine cell fate determination signals, like BSP1, BMP2, PPARG, FABP4, ACAN, and COL2A. Notably, osteogenic markers were dramatically overexpressed (more than 100-folds rather than tissue culture plate) in response to biomechanical characteristics of the ZIF-8 layer. Conclusion: Hence, surface modification of cell culture platforms with MOF nanostructures proposed as a powerful nanomedical approach for selectively guiding stem cells for tissue regeneration. In particular, PP/PDA/ZIF-8 membrane presented ideal characteristics for using as a barrier membrane for guided bone regeneration (GBR) in periodontal tissue engineering.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Polipropilenos/química , Polipropilenos/farmacologia , Zeolitas/química , Diferenciação Celular/efeitos dos fármacos , Indóis/química , Osteogênese/efeitos dos fármacos , Polímeros/química , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
17.
Artigo em Inglês | MEDLINE | ID: mdl-32784702

RESUMO

In this study, the adsorption of Fe(III) from aqueous solution on zeolite and bentonite was investigated by combining batch adsorption technique, Atomic adsorption spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses. Although iron is commonly found in water and is an essential bioelement, many industrial processes require efficient removal of iron from water. Two types of zeolite and two types of bentonite were used. The results showed that the maximum adsorption capacities for removal of Fe (III) by Zeolite Micro 20, Zeolite Micro 50, blue bentonite, and brown bentonite were 10.19, 9.73, 11.64, and 16.65 mg.g-1, respectively. Based on the X-ray photoelectron spectroscopy (XPS) and X-ray fluorescence (XRF) analyses of the raw samples and the solid residues after sorption at low and high initial Fe concentrations, the Fe content is different in the surface layer and in the bulk of the material. In the case of lower initial Fe concentration (200 mg.dm-3), more than 95% of Fe is adsorbed in the surface layer. In the case of higher initial Fe concentration (4000 mg.dm-3), only about 45% and 61% of Fe is adsorbent in the surface layer of zeolite and bentonite, respectively; the rest is adsorbed in deeper layers.


Assuntos
Adsorção , Bentonita/química , Ferro/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Zeolitas/química , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética
18.
J Chromatogr A ; 1626: 461358, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32797837

RESUMO

In this study, the in-situ conversion of the synthesized Co-Al layered double hydroxide (Co-Al LDH) nanosheets to three dimensional hierarchical zeolitic imidazolate framework-67 (3D HZIF-67) was presented as a cost-effective, highly efficient, flexible and robust sorbent to carry out the microextraction process. In the first stage, the anodized aluminum foil was prepared electrochemically. Then, the Co-Al LDH precursor was constructed on the surface of the previously-prepared anodized Al foil applying in-situ formation approach. The procedure is followed by the conversion of the prepared Co-Al LDH film to 3D HZIF-67 film via a facile solvothermal method without adding cobalt salt. The in-situ prepared 3D HZIF-67-anodized Al was used for the thin film microextraction (TFME) of caffeine. The effective factors in TFME procedure were investigated and optimized through applying Central Composite Design (CCD). In the obtained optimal condition, the calibration curves for TFME-HPLC-UV of caffeine were linear in the range of 1-200 µg L-1 with the coefficient of determination (r2) higher than 0.9915. The limits of detection were 0.33 and 0.38 µg L-1, in water and urine matrices, respectively. Moreover, the enrichment factors (EFs) and absolute recoveries (%AR) were also calculated as 173-198 and 57.1%-65.3%, respectively. The inter-day relative standard deviations (RSDs) were evaluated as the method precision for 20 and 200 µg L-1 of spiked sample and were between 4.9-6.1%. The repeatability of the preparation step was investigated as batch-to-batch reproducibility and it was found to be 4.9%; as a result, the reproducibility of the presented film was approved. Finally, the proposed method was utilized to determine caffeine (as the model analyte) from different types of real samples including urine, coffee, beverage (Pepsi) and shampoo. The obtained recoveries (higher than 88%) confirmed the capability of the method for real sample analysis.


Assuntos
Alumínio/química , Cafeína/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cobalto/química , Hidróxidos/química , Imidazóis/química , Raios Ultravioleta , Zeolitas/química , Adsorção , Eletrodos , Limite de Detecção , Microscopia de Força Atômica , Porosidade , Reprodutibilidade dos Testes , Solventes/química , Propriedades de Superfície
19.
J Chromatogr A ; 1625: 461284, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709334

RESUMO

In this work, a class of novel and eco-friendly open-tubular (OT) chiral column was presented for the first time by one step preparation with zeolite imidazolate framework-8 (ZIF-8) and bovine serum album (BSA) based on electrostatic adsorption and adsorption affinity. This stationary phase materials combined the features of large surface areas and adsorption affinity of ZIF-8, and also the multiple chiral binding sites of BSA, which contributes to the π-interaction and hydrophobic interaction with the analytes. The separation performance of BSA@ZIF-8-OT chiral columns was evaluated with a miniaturized capillary electrochromatography and amperometric detection (mini-CEC-AD) system; in particular, nine groups of model molecules, including homologues, structural isomers, and chiral compounds, were baseline separated under the certain optimum conditions. The RSDs of run-to-run, day-to-day, column-to-column, and batch-to-batch reproducibility were less than 13.8 %. Furthermore, the prepared OT columns were successfully applied to fast analysis of ephedrine isomers in Chinese herb ephedra, and the LODs achieved 1.5-2.0 ng mL-1 (S/N=3) by an electrophoretic stacking technique of moving chemical reaction boundary. This mini-CEC-AD system with BSA@ZIF-8-OT chiral columns provides a promising potential in pharmaceutical analysis due to its fast, sensitive, enantioselective, and low-cost characteristics.


Assuntos
Eletrocromatografia Capilar/métodos , Imidazóis/química , Soroalbumina Bovina/química , Zeolitas/química , Adsorção , Animais , Bovinos , Concentração de Íons de Hidrogênio , Limite de Detecção , Reprodutibilidade dos Testes , Estereoisomerismo
20.
Chemosphere ; 258: 127274, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32569956

RESUMO

The main aim of this work was to develop sustainable catalyst from geothermal waste by hydrothermal process for enhanced biohydrogen production. The effects of Si/Al ratio and pH neutralization on the catalyst were also investigated to provide further insight into the hydrogen production capability. Results have shown with increasing Si/Al ratio, a lower amount of catalyst was synthesized and smaller particle size was obtained. pH neutralization treatment resulted in higher conversion compared to non-neutralized ones. Meanwhile, the highest conversion of biohydrogen from ethanol through steam reforming process (95.19%) was obtained from catalyst with pH neutralization treatment and Si/Al ratio of 10. The catalyst developed in this study was concluded to be suitable for framework/supporting catalyst due to relatively low selectivity.


Assuntos
Biocombustíveis/análise , Etanol/química , Hidrogênio/análise , Resíduos Industriais/análise , Zeolitas/química , Óxido de Alumínio/química , Catálise , Temperatura Alta , Concentração de Íons de Hidrogênio , Dióxido de Silício/química , Vapor , Propriedades de Superfície
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