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1.
Artigo em Inglês | MEDLINE | ID: mdl-39450756

RESUMO

The conventional slippery liquid-infused porous surfaces (SLIPSs) provide relatively limited corrosion protection and self-healing performance for AZ31 Mg alloys. To this end, 8-hydroxyquinoline (8-HQ) was incorporated into a zirconium-based metal-organic framework UiO-66 through coordination (8-HQ@UiO-66), which was then dispersed into silicone oil to fabricate nanoparticle-enhanced-SLIPSs (8-HQ@UiO-66-SLIPSs). Especially, the influences of 8-HQ@UiO-66 concentration on the surface morphology, surface hydrophobicity, and corrosion resistance were studied. It was found that the surface hydrophobicity first increased and then decreased with increasing concentration, showing the highest water contact angle of 121.2° at a concentration of 1 mg mL-1 (8-HQ@UiO-66-SLIPS-1). This was attributed to the development of well-constructed hierarchical micro/nanostructures. Moreover, it also exhibited the best anticorrosion property, with the lowest corrosion current density of 1.24 × 10-10 A cm-2 and the highest impedance modulus of 9.88 × 108 Ω cm2 at 0.01 Hz, primarily associated with the synergistic interaction of 8-HQ and UiO-66. Further, the self-healing performance was evaluated using the scanning vibration electrode technique (SVET), verifying the superior self-healing performance of 8-HQ@UiO-66-SLIPS-1. Hence, the nanoparticle-enhanced-SLIPSs exhibit considerable potential in the corrosion protection of Mg alloys, thereby accelerating their extensive applications in industry.

2.
Sci Rep ; 14(1): 25177, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39448618

RESUMO

In this study, adsorption of volatile organic compounds (VOCs) (here just gasoline vapor) by activated carbon- modified UIO-66 was investigated. First, activated carbon prepared from mesquite grain (ACPMG) and then UIO/ACPMG nanohybrid was synthesized by the solvothermal method. In following, the effect of main key parameters which effect on the surface and adsorption capacity such as the ratio of ACPMG to UIO-66 was studied. Physiochemical changes of as- synthesized samples were investigated by TGA, HR-TEM, PSD, SEM, EDX/MAP, BET, FT-IR, XRD, and XPS. It was found the UIO/ACPMG20% nanohybrid had the highest adsorption capacity (391.304 mg/g) for VOCs compared with the other samples, while the adsorption capacity of UIO-66, UIO/ACPMG10% nanohybrid, and UIO/ACPMG30% nanohybrid was 298.871, 309.523, and 320 mg/g respectively. UIO/ACPMG20% nanohybrid desorbed 285.71 mg/g of the adsorbed gasoline, which is an excellent result in desorption. So, the sample of UIO/ACPMG20% nanohybrid was selected as the optimum nano-adsorbent. In other hand, all the nano-adsorbent showed a rapid kinetic behavior for gasoline vapor adsorption and the maximum time for reaching a high adsorption capacity approximately was obtained in 20 min. Density functional theory calculations also performed to understand the adsorption characteristics of gasoline vapor on activated carbon-modified UIO-66.

3.
Biosensors (Basel) ; 14(10)2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39451725

RESUMO

Arginine has been widely applied in the food industry as coloring agents, flavoring agents, and nutritional fortifiers. It is also one of the major components of feed additives. Currently, methods for the highly selective detection of arginine remain absent. For accurate and sensitive detection of L-arginine, a novel ratiometric fluorescence assay based on Ru@UiO-66-NH2 was developed and demonstrated in this study. Under optimized detection conditions, the limit of detection (LOD) of this assay for L-arginine was 2.32 µM, which is superior to most assays reported to date. Meanwhile, Ru@UiO-66-NH2 showed good stability within 30 days, demonstrating the wide applicability of the proposed assay. The spike-and-recovery rates of the proposed assay for L-arginine in real samples (e.g., tea, grape juice, and serum) were 84.27-113.09%. Overall, the proposed assay showed high sensitivity, good reproducibility, and excellent stability in the detection of L-arginine in both buffer and real samples.


Assuntos
Arginina , Limite de Detecção , Arginina/análise , Fluorescência , Rutênio/química , Espectrometria de Fluorescência , Sucos de Frutas e Vegetais/análise , Técnicas Biossensoriais , Chá/química , Reprodutibilidade dos Testes
4.
Pest Manag Sci ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422189

RESUMO

BACKGROUND: Metal-organic frameworks have the advantages of easy synthesis, high loading capacity and good biocompatibility, making them essential materials for constructing pesticide nano-delivery systems. In this study, a pH-responsive nano-controlled-release formulation Chl@UiO-66 was prepared using UiO-66 as the nano-scale carrier for adsorbing chlorantraniliprole (Chl). RESULTS: The appearance, pesticide loading, release behaviour, insecticidal activity, long-term control efficacy and safety of Chl@UiO-66 for non-target organisms were extensively evaluated. The results showed that the prepared Chl@UiO-66 was a regular octahedron with a uniform particle size of 230 nm and pesticide loading of 15.62%. The release of pesticides under alkaline conditions was superior to that under acidic and neutral conditions, which showed pH-responsive performance. Chl@UiO-66 had an excellent ability to protect pesticides from ultraviolet degradation. Compared with chlorantraniliprole suspension concentrate, Chl@UiO-66 had a better control effect against Spodoptera frugiperda and long-term control efficacy. The prepared nano-controlled-release formulation had low toxicity to zebrafish, earthworms and human BEAS-2B cells. CONCLUSION: Chl@UiO-66 is a new pesticide formulation with high efficacy and low toxicity that provides a smart controlled-release solution. © 2024 Society of Chemical Industry.

5.
ChemSusChem ; : e202401697, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422284

RESUMO

Li-O2 batteries (LOBs) have garnered significant attention in recent years due to high theoretical specific capacity, however, the sluggish charge-discharge reaction kinetics and rapid failure under high current densities have hindered their further application. This work presents a photo-responsive catalyst (UIO-66-NH2) supported on carbon cloth, which could enhance the reaction kinetics of LOBs and improve the discharge capacity under high current densities. It demonstrates that under light, the overpotential decreases by 0.9 V, and the discharge capacity reaches an impressive 4.8 mAh cm-2 at a current density of 0.5 mA cm-2. This finding is expected to inspire the development of various novel MOF-based photoelectrodes for LOBs.

6.
J Hazard Mater ; 480: 136017, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39362121

RESUMO

Considering the unexpected nuclear power waste emission and potential nuclear leakage, the exploration of robust materials for the effective capture and storage of radioactive iodine is of great importance but still remains a challenge. In this work, we report the rational synthesis of functionalized NH2-UiO-66-on-ZIF-67 architecture to enhance the static adsorption and retention of volatile iodine. Such MOF-on-MOF heterostructures was fabricated through seeding ZIF-67 core on the surface of NH2-UiO-66 satellite via a facile polyvinylpyrrolidone (PVP) regulated internal extended growth strategies. NH2-UiO-66-on-ZIF-67 exhibited unique core-satellite structure, which significantly promotes the binding interactions with iodine through synergizing of the N-rich imidazole moieties and surface functionalized amino groups within the porosity channels. As a result, the as fabricated NH2-UiO-66-on-ZIF-67 achieves enhanced mass diffusion and high capture capacity of 3600 mg/g for iodine vapor under static sorption conditions. Moreover, water vapor in humid conditions (relative humidity of 18 %) has almost no effect on the static iodine adsorption performance of the material. This study sheds light on a reliable MOF-on-MOF hybrid strategy for effective radioiodine treatment to ensure the safety nuclear waste management.

7.
Talanta ; 282: 126972, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39342672

RESUMO

Lysine (Lys) is an essential nutrient that plays a crucial role in the growth and development of living organisms. Chiral analysis of Lys holds significant importance for ensuring the safety of food, pharmaceuticals, and health products. In this work, an achiral Zr-based metal organic frameworks (MOFs), UiO-66-NH2, was proposed as a fluorescent probe to achieve rapid response to l-lysine (L-Lys) in solution. Additionally, Zr4+ in the skeleton of UiO-66-NH2 framework exhibited different binding capacities towards Lys enantiomers, leading to distinct fluorescence responses for L-Lys and d-lysine (D-Lys). Leveraging these properties, the UiO-66-NH2 probe enabled accurate determination of L-Lys concentrations in solution, as well as the enantiomeric excess (ee) values of Lys solutions. Notably, in the detection of Lys enantiomers, the achiral UiO-66-NH2 acted as both a chiral selector and a fluorescent indicator, greatly improving the efficiency and stability of the detection system. The probable mechanism was further elucidated by pH titration experiments and density functional theory calculations. Additionally, the general applicability of this mechanism was validated by similar amino MOFs. The application of the UiO-66-NH2 fluorescent probe in analysis of infant formula milk powders and liquid milk samples confirmed the reliability of the method. Moreover, the construction of fluorescence test paper by immobilizing UiO-66-NH2 onto filler papers enabled the rapid identification of Lys enantiomers. Compared to previous fluorescent analyses of chiral amino acids assisted by additional metal ions, this study presented a novel approach and methodology that offers high efficiency, stability, reproducibility and reusability for the identification and detection of Lys enantiomers, highlighting the potential of the UiO-66-NH2 fluorescent probe in advancing analytical techniques.

8.
Chemosphere ; 364: 143273, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39241840

RESUMO

MXene-based membranes, as a type of modified membrane, have unique structures that attract attention for water treatment but suffer from low water flux. To address this, MXene was manipulated with UiO-66-NH2 nanoparticles to create UiO-66-NH2@MXene 2D-nanocomposites for the modification of the PES membrane. Herein, we synthesized a novel modified MXene-based PES membrane. The MXene, UiO-66-NH2, and UiO-66-NH2@MXene were assessed using the Fourier transform infrared, X-ray diffraction pattern, X-ray photoelectron spectroscopy, and zeta potential analysis. Field emission scanning electron microscopy was used to evaluate the MXene-based materials and prepared membranes, and the surface topography of the fabricated membranes was studied using atomic force microscopy. The membrane modified by 0.25 wt% of modifier was able to not only remove 72% and 81% of methylene blue and crystal violet cationic dyes, but also recorded more than 91% rejections for methyl blue, methyl orange, acid fusion, and Congo red anionic dyes. Using the same membrane, salt rejections of 91%, 87%, 79%, and 62% were achieved for Na2SO4, MgSO4, MgCl2, and NaCl, respectively. Water flux was also increased by more than 4 times in the membrane modified with 0.25 wt% of the novel nanocomposite modifier, and the water contact angle of the membrane with 0.5 wt% decreased from 65° to 38° compared to the pristine PES membrane. Besides, the anti-fouling properties were exceptionally improved in the membranes modified by the introduced UiO-66-NH2@MXene nanocomposite modifier.


Assuntos
Membranas Artificiais , Nanocompostos , Purificação da Água , Nanocompostos/química , Purificação da Água/métodos , Poluentes Químicos da Água/química , Filtração/métodos , Estruturas Metalorgânicas/química , Corantes/química , Polímeros/química , Azul de Metileno/química
9.
J Sep Sci ; 47(18): e2400296, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39276082

RESUMO

A simple and quick fiber-in-tube solid-phase microextraction (FIT-SPME) was introduced for the extraction and determination of nine polycyclic aromatic hydrocarbons followed by a high-performance liquid chromatography-ultraviolet detector in refinery water samples. For this purpose, a water-resistant metal-organic framework with a high surface area called UiO-66 has been applied in the form of an electrospun coating on stainless steel wires. After that, all the fibers were packed in the lumen of a stainless-steel tube to make the extraction phase. Both one variable at a time and experimental design methods have been used to optimize effective parameters on FIT-SPME. Under optimum conditions, the method demonstrated good linearity between 0.5 and 1000.0 µg/L with a coefficient of determination greater than 0.9906. Furthermore, the limits of detection values ranged from 0.2 to 1.5 µg/L. The intra-day and inter-day relative standard deviations were < 8.4% and < 9.7%, respectively. Lastly, the proposed method was applied to extract and determine analytes in four refinery water samples as well as surface water containing high total dissolved solids, and well waters where satisfactory results have been obtained.

10.
Small ; : e2405831, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39308233

RESUMO

Recent research has demonstrated the degradation of organophosphonates through hydrolysis using microporous UiO-66-NH2-fabric composites. Yet, challenges remain due to the limitations of organophosphonates accessing active sites in large, engineered granules. To address this, an innovative approach to integrate mesoporous UiO-66-NH2 onto various fabrics is provided, thereby overcoming previous mass transfer limitations. Mesoporosity in the UiO-66-NH2-fabric is attributed to the amphoteric cocamidopropylbetaine (CAPB) surfactant which templates the mesochannel construction. Unexpectedly, because the synthesis is aqueous, benign, low temperature (60°C), and avoids strong acids and toxic solvents, it is compatible with fragile supports such as untreated cotton. The UiO-66-NH2-fabric composite formed using treated polypropylene (PP) attains a BET specific surface area of 360 m2 g-1 comp. Remarkably, the mesoporous UiO-66-NH2-composites exhibit a pore volume as large as 0.2 cm3 g-1 comp, 33% in the mesoporous range, which is higher than other previous reports. Practically, the mesoporous UiO-66-NH2-treated PP composite enhances the rate of methyl paraoxon (DMNP) degradation, showing a t1/2 value that is 15 times faster than microporous UiO-66-NH2 composites measured under the same conditions. Similar trends are observed in the degradation of actual nerve agents. These composites hold significant potential across diverse applications, including filtration, protection, and catalysis.

11.
ACS Appl Mater Interfaces ; 16(39): 52445-52454, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39292754

RESUMO

Many metal-organic frameworks (MOFs) incorporate nodes that are metal oxide clusters, and ligands that have been observed on these nodes include formates, acetates, water, hydroxyl groups, and others, all of which are potentially important in affecting reactivities for applications in separations, catalysis, and sensing. Formate is a common node ligand, arising from formic acid used as a modulator and from N,N-dimethylformamide used as a solvent in MOF syntheses. Yet only little work has been reported characterizing the reactivities of node formate ligands. Infrared spectra reported here show that formate bonds to two types of sites on the paired Hf6O8 nodes of hcp UiO-66, namely, defect and µ2-OH sites. Quantifying the number of formate ligands by 1H NMR spectroscopy of digested samples showed an almost equal number of formate ligands on the two sites, indicating the likelihood that they neighbor each other. These formate ligands interact with water molecules, reversibly switching their bonding from bidentate to monodentate. The formates on µ2-OH sites of hcp Hf-UiO-66 interact much more strongly with water than those on defect sites of the same node, and both interact more strongly than isolated defect sites of Hf-UiO-66. Correspondingly, the catalytic activities of hcp UiO-66 determined as turnover frequencies on each site are approximately twofold higher than those on UiO-66, bolstering the inference that methanol dehydration is catalyzed by a node defect site and a neighboring node µ2-OH site. The results show how MOFs, with their well-defined node structures, provide unprecedented opportunities to understand details of reactivities and catalysis on metal oxide clusters, in contrast to bulk metal oxide surfaces.

12.
Int J Pharm ; 665: 124665, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39236772

RESUMO

Stimuli-responsive nanoplatforms have been popular in controlled drug delivery research because of their ability to differentiate the tumor microenvironment from the normal tissue environment in a spatiotemporally controllable manner. The synergistic therapeutic approach of combining cancer chemotherapy with photothermal tumor ablation has improved the therapeutic efficacy of cancer therapeutics. In this study, a UiO-66 metal organic framework (MOF)-based system loaded with doxorubicin (DOX), surface decorated with the photothermal agents indocyanine green (ICG) and polydopamine (PDA), and conjugated with transferrin (TF) was successfully designed to operate as a responsive system to pH changes, featuring photothermal capabilities and target specificity for the purpose of treating breast cancer. The synthesized nanoplatform benefits from its uniform size, excellent DOX encapsulation efficiency (91.66 %), and efficient pH/NIR-mediated controlled release of the drug. In vitro photothermal studies indicate excellent photothermal stability of the formulation even after 6 on-off cycles of NIR irradiation. The in vitro cytotoxicity assessment using an NIR laser (808 nm) revealed that the DOX-loaded functionalized UiO-66 nanocarriers had outstanding inhibitory effects on 4T1 cells because of synergistic chemo-photo therapies, with no substantial toxicity by the carriers. In addition, cellular uptake evaluations revealed that UiO-DOX-ICG@PDA-TF could specifically target 4T1 cells on the basis of receptor-mediated internalization of transferrin receptors. Additionally, in vivo toxicity studies in Wistar rats indicated no signs of significant toxicity. The UiO-based nanoformulations effectively inhibited and destroyed cancer cells under 808 nm laser irradiation because of their minimal toxicity, strong biocompatibility, and outstanding synergistic chemo/photothermal/photodynamic treatment.


Assuntos
Doxorrubicina , Verde de Indocianina , Indóis , Estruturas Metalorgânicas , Fotoquimioterapia , Transferrina , Verde de Indocianina/administração & dosagem , Verde de Indocianina/química , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Doxorrubicina/química , Transferrina/química , Transferrina/administração & dosagem , Estruturas Metalorgânicas/química , Animais , Linhagem Celular Tumoral , Indóis/química , Indóis/administração & dosagem , Indóis/farmacologia , Camundongos , Fotoquimioterapia/métodos , Feminino , Polímeros/química , Liberação Controlada de Fármacos , Ratos , Nanopartículas/química , Portadores de Fármacos/química , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia
13.
Int J Biol Macromol ; 279(Pt 4): 135557, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39265898

RESUMO

Enzyme immobilization is an effective strategy for achieving efficient and sustainable enzyme catalysis. As a kind of promising enzyme-loading materials, the systematic research on zirconium based metal organic frameworks (Zr-MOFs) about immobilization performance at molecular level is still in its initial stage. In this work, UiO-66 was functionalized with various groups (-H, -NH2, -COOH, -OH, -2OH) for the immobilization of cytochrome c (Cyt c) and antioxidant enzyme catalase (CAT). Then the effects of surface-functionalized UiO-66 derivatives on the loading efficiency, enzyme stability and catalysis kinetics were systematically investigated. In addition, the affinity constants of Cyt c and CAT towards UiO-66-series MOFs carriers were also compared. The results have shown that hydroxyl group functionalized UiO-66 represents the highest enzyme loading capacity, enhanced activity and improved stability for Cyt c and CAT possibly due to high surface area and suitable microenvironments as well as enhanced affinity towards the enzymes provided by the introduction of a single hydroxyl group. Our research would foresee immense potential of MOFs in engineering biocatalysts.


Assuntos
Catalase , Citocromos c , Estabilidade Enzimática , Enzimas Imobilizadas , Estruturas Metalorgânicas , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Catalase/química , Catalase/metabolismo , Estruturas Metalorgânicas/química , Citocromos c/química , Citocromos c/metabolismo , Cinética , Zircônio/química , Biocatálise
14.
Chemosphere ; 365: 143321, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39299465

RESUMO

In the present study, the potential of pyrolytic coke (PC) and PC modified with UiO-66 nanoparticles as adsorbents for removing mono-ethylene glycol (MEG) from aqueous solutions was studied. Different experimental techniques were used to investigate the properties of adsorbents. The modification of the PC surface (6.91 m2/g) with UiO-66 significantly enhanced the specific surface area of the PC/UiO-66 composites, increasing it to 379.31 m2/g. Maximum MEG adsorption using PC (84.21%) and PC/UiO-66 (96.75%) was recorded at pH equal to 5 and 7, MEG quantity of 100 mg/L, temperature of 25 °C, adsorbent dosage of 1 g/L, and treatment time of 120 min, respectively. The Langmuir isotherm adsorption capacities for MEG removal using PC and PC/UiO-66 were determined to be 265 mg/g and 291 mg/g, respectively. The KF and AT values for the MEG adsorption were obtained at 128.1 mg/g (L/mg)1/n and 11.05 L/g, indicating the more pronounced affinity of the PC/UiO-66 towards MEG than the PC sample. The enthalpy, entropy, and Gibbs free energy were determined to be negative; thus, the MEG adsorption was exothermic and spontaneous in the range of 25-50 °C. The results demonstrated that the experimental data adheres to a pseudo-first-order kinetic. The adsorbents were recycled up to five stages, and the results showed that after five cycles, no significant decrease in the adsorption efficiency occurred, making them suitable for repeated utilization in the adsorption process.


Assuntos
Coque , Etilenoglicol , Poluentes Químicos da Água , Adsorção , Poluentes Químicos da Água/química , Etilenoglicol/química , Cinética , Purificação da Água/métodos , Concentração de Íons de Hidrogênio , Termodinâmica , Temperatura , Nanopartículas/química
15.
J Environ Manage ; 370: 122572, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39299111

RESUMO

In this study, a porous hollow nanofiber SnO2 was decorated with UiO-66-NH2 nanoparticles with straightforward solvothermal method and utilized for sonocatalytic degradation of tetracycline (TC) by ultrasonic irradiation (USI). The prepared materials were characterized using different techniques such as SEM, EDS, FTIR, XRD, BET, XPS, UV-DRS, EIS, and zeta potential. SnO2 PHNF/UiO-66-NH2 nanocomposite offered the highest apparent rate constant of 0.0397 min-1 which was 6.3 and 3.1 times higher than those obtained for SnO2 PHNF and UiO-66-NH2, respectively. The integration of nanocomposite components revealed the synergy factor of 1.58, which can be due to the created heterojunctions resulted in efficiently charge carriers separation and retaining high redox ability. The effects of different affecting parameters such as TC initial concentration, pH of the solution, catalyst dosage, trapping agents, and coexisting anions on the catalytic performance were examined. The inhibitory effects of anions were confirmed to be decreased in the sequence of Cl- > NO3- > SO42-, while the sonocatalytic efficiency of the nanocomposite improved considerably in the presence of humic acid and bicarbonate. Also, the excellent performance of the catalyst was preserved during six successive cycles, suggesting the high stability of the prepared catalyst. In addition, based on the scavenger analysis, the created O2·-, OH·, and holes were contributed to the TC degradation. In conclusion, the creation heterojunction is an impressive methodology for improving the sonocatalytic activity of a catalyst, and SnO2 PHNF/UiO-66-NH2 nanocomposite was introduced as a satisfactory catalyst in sonocatalytic degradation of organic contaminants.

16.
Chem Asian J ; : e202401035, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254915

RESUMO

An optimised synthesis of the metal-organic framework (MOF) UiO-66(Ce) is reported using a modulator-free route, yielding ~5 g of material with high crystallinity and 22% ligand defect. Two methods developed for loading gold nanoparticles onto the MOF. The first uses a double-solvent method to introduce HAuCl4 onto UiO-66(Ce), followed by reduction under 5% H2 in N2, while the second is a novel one-pot method where HAuCl4 is added to the synthesis mixture, forming Au nanoparticles within the pores of the UiO-66(Ce) during crystallisation. Analysis using powder X-ray diffraction (PXRD), nitrogen adsorption isotherms, transmission electron microscopy and small-angle X-ray scattering (SAXS) reveals that the two-step double-solvent method yields gold crystallites on the external surface of the MOF particles that are visible by PXRD. In contrast, the one-pot method forms smaller gold crystallites, with a distribution of sizes centred on ~4 nm diameter as seen by SAXS, with evidence from PXRD for the smallest particles being present within the MOF structure. The Au-loaded UiO-66(Ce) materials are evaluated for the catalytic oxidation of vanillyl alcohol to vanillin at 60 °C. Our findings indicate that incorporating Au nanoparticles via the one-pot synthesis method, enhances redox activity, achieving 43% conversion and 90% selectivity towards vanillin.

17.
Environ Sci Pollut Res Int ; 31(39): 52485-52500, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39150667

RESUMO

The presence of antibiotics in water sources is a significant concern due to their potential environmental impact and the risks to human health. In the present research, hierarchically mesoporous UiO-66 (HP-UiO-66) with a high surface area (1011 m2/g) and large pore volume was synthesized using the reflux method on the liter scale. The successful synthesis was confirmed by FT-IR, XRD, FESEM/EDS, N2-adsorption/desorption, and zeta potential techniques. The HP-UiO-66 was utilized to remove two large structure antibiotics, chlortetracycline hydrochloride (CTC), and oxytetracycline (OTC). Box Behnken design was used to investigate the factors affecting the removal process and the interactions between them. The maximum adsorption capacities for OTC and CTC antibiotics were 252.9 mg/g and 234.2 mg/g at 35 °C, respectively. The sum of the normalized error method was applied to the analysis of various error functions in the nonlinear fitting of equilibrium and kinetic data. The CTC and OTC adsorption kinetic followed a fractal-like pseudo-second-order model. The Langmuir isotherm fitted well to adsorption data. The results demonstrate that HP-UiO-66 can be used as a recyclable and efficient adsorbent for large molecule antibiotics removal.


Assuntos
Antibacterianos , Águas Residuárias , Poluentes Químicos da Água , Antibacterianos/química , Poluentes Químicos da Água/química , Águas Residuárias/química , Adsorção , Cinética , Purificação da Água/métodos , Oxitetraciclina/química , Clortetraciclina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Porosidade
18.
Talanta ; 280: 126742, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39173251

RESUMO

The simple, effective and highly sensitive detection of hydrogen peroxide (H2O2), which belongs to the reactive oxygen species (ROS), at low concentrations plays an indispensable role in the field of environmental protection, biological research and safety. In this study, a dual-mode optical biosensor, UiO-66@OPD, was developed based on the inherent peroxidase mimicking activity of UiO-66 (Zr) and the optical reaction of ortho-phenylenediamine (OPD) by extending the π-system through oxidative coupling, prototropism and elimination to form OPDox, thereby exhibiting strong orangish absorbance and greenish fluorescence. The catalase-mimicking activity of UiO-66 (Zr) was demonstrated by the catalytic oxidation of methylene blue in the presence of H2O2. Moreover, the Michaelis-Menten kinetic model confirmed the intrinsic peroxidase-like activity of UiO-66@OPD as a modified MOFzyme. The synthesized UiO-66 (Zr) facilitated the oxidation of OPD to OPDox by degrading H2O2 to the hydroxyl radicals. During the oxidation process, the absorption peak at 415 nm and the fluorescence peak at 565 nm of the synthesized probe were significantly enhanced by increasing the H2O2 concentration. Moreover, a colorimetric and fluorometric ultrasensitive sensor shows a good linear relationship between the intensity enhancement and H2O2 concentration in the range of 0-600 nM for absorption and fluorescence spectra with R2 = 0.9772, and R2 = 0.9948, respectively. To demonstrate the biological performance and biocompatibility of UiO-66@OPD as a biosensor, MTT evaluation was performed for the three cell lines MCF-10 A, HEK293 and A549, indicating high biocompatibility and good cell viability for biological applications. Ultimately, this convenient, environmentally friendly, biocompatible and cost-effective catalase-mimicking-based sensor system will open a new perspective for the development of portable kite-based biosensors In vitro.


Assuntos
Técnicas Biossensoriais , Peróxido de Hidrogênio , Espécies Reativas de Oxigênio , Humanos , Técnicas Biossensoriais/métodos , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/análise , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Fenilenodiaminas/química , Estruturas Metalorgânicas/química , Limite de Detecção , Zircônio/química , Materiais Biocompatíveis/química
19.
Small Methods ; : e2401141, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39149767

RESUMO

Passive radiative cooling represents a transformative approach to achieving sustainable cooling on Earth without relying on energy consumption. In this research, the optical characteristics of five readily accessible metal-organic frameworks (MOFs): ZIF-67(Co), MOF-74(Ni), HKUST-1(Cu), MOF-801(Zr), and UiO-66(Zr) are meticulously explored. The objective is to identify the pivotal factors that influence their ability to facilitate radiative cooling. Through an in-depth analysis encompassing spectroscopic features, surface texture, and porosity, it is found that the MOFs' cooling efficacy is largely influenced by their optical bandgaps and functional groups, although other factors like chemical composition and structural characteristics remain to be considered. Notably, UiO-66(Zr) emerged as the standout performer, boasting an impressive solar reflectance of 91% and a mid-infrared emissivity of 96.8%. Remarkably, a fabric treated with UiO-66(Zr) achieved a substantial sub-ambient cooling effect, lowering temperatures by up to 5 °C and delivering a cooling power of 26 W m-2 at 300 K. The findings underscore the vast potential of MOFs in offering new opportunities to advance passive radiative cooling technologies, paving the way for their extensive application in this field.

20.
J Hazard Mater ; 477: 135237, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39094305

RESUMO

This study presents a thorough investigation of the novel application of graphene oxide (GO) modified with melamine formaldehyde to fabricate granular three-dimensional GO (3D-GO), followed by the introduction of UiO-66 doping (3D-GO/U) for high uranium (U) adsorption. The U(VI) adsorption isotherms revealed that 3D-GO/U-10 with 10 % UiO-66 incorporation exhibited an impressive adsorption capacity of 375.5 mg g-1 and remained high U(VI) sorption performance in wide pH range. The introduction of UiO-66 to 3D-GO (3D-GO/U-10) led to the deagglomeration of the UiO-66 particles. The in situ surface-enhanced-Raman-spectroscopy-analysis and density-functional-theory simulations showed the symmetric metal center site Zr-O2 on UiO-66 was discovered to exhibit the highest adsorption energy (-3.21 eV) for U(VI) species due to the electrons transfer from the oxygen atom to U(VI) drives the covalent bonding between the symmetric metal center sites Zr-O2 and U(VI) on 3D-GO/U-10. The 3D-GO/U-10 was regenerated using a 0.1 M Na2CO3/0.01 M H2O2 solution and achieved up to 89.7 % U(VI) removal in the 5th cycle. The continuous flow column experiments results revealed 3D-GO/U-10 can regenerate and maintain a U(VI) removal capacity of ∼76 % for up to 4 cycles column experiments. Therefore, 3D-GO/U-10 exhibits great potential for removing U(VI) from water bodies.

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