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1.
Sci Rep ; 14(1): 11969, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796550

RESUMO

Hercynite magnetic nanoparticles were produced through the co-precipitation of ferrous and aluminum cations. The surface of hercynite was respectively coated with silica, 2,4,6-trichloro-1,3,5-triazine, and 1H-pyrazole-3,5-dicarboxylic acid to provide a suitable substrate for Pd(II) loading, furnishing Pd@Her-TCT-PDA. Subsequently, the introduced Pd(II) was reduced to Pd(0) using NaBH4. FT-IR, EDS, XRD, TGA, TEM and SEM images were the characteristic methods to prove the success of catalyst synthesis. The SEM image illustrated the particles with a nanosize of 25-50 nm and TEM image confirmed the presence of Pd nanoparticles with sizes lower than 2 nm. EDS elemental analysis of the catalyst proved the existence of Pd, Fe, and Al atoms along with the C, O, N, and Si atoms belong to the heterocyclic moieties. VSM analysis clarified a considerable drop in the magnetic properties of the hercynite core of the final catalyst due to its modified surface. TGA curve demonstrated that Pd@Her-TCT-PDA contains 20% organic content, attributed to the anchored heterocyclic ligands. Finally, Pd@Her-TCT-PDA was employed along with NaBH4 as a catalytic system to reduce completely the nitro group of aromatic compounds to their corresponding amines. The recyclability tests showed low drop in the catalytic activity of Pd@Her-TCT-PDA after third run with negligible leaching of Pd NPs.

2.
Sci Rep ; 14(1): 11450, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769394

RESUMO

A mesoporous silica nanoparticle (MSN) coated with polydopamine (PDA) and loaded with umbelliprenin (UMB) was prepared and evaluated for its anti-cancer properties in this study. Then UMB-MSN-PDA was characterized by dynamic light scattering (DLS), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM) and FTIR methods. UV-visible spectrometry was employed to study the percentage of encapsulation efficiency (EE%). UMB-MSN-PDA mediated cell cytotoxicity and their ability to induce programmed cell death were evaluated by MTT, real-time qPCR, flow cytometry, and AO/PI double staining methods. The size of UMB-MSN-PDA was 196.7 with a size distribution of 0.21 and a surface charge of -41.07 mV. The EE% was 91.92%. FESEM and TEM showed the spherical morphology of the UMB-MSN-PDA. FTIR also indicated the successful interaction of the UMB and MSN and PDA coating. The release study showed an initial 20% release during the first 24 h of the study and less than 40% during 168 h. The lower cytotoxicity of the UMB-MSN-PDA against HFF normal cells compared to MCF-7 carcinoma cells suggested the safety of formulation on normal cells and tissues. The induction of apoptosis in MCF-7 cells was indicated by the upregulation of P53, caspase 8, and caspase 9 genes, enhanced Sub-G1 phase cells, and the AO/PI fluorescent staining. As a result of these studies, it may be feasible to conduct preclinical studies shortly to evaluate the formulation for its potential use in cancer treatment.


Assuntos
Antineoplásicos , Indóis , Nanopartículas , Polímeros , Dióxido de Silício , Humanos , Indóis/química , Indóis/farmacologia , Dióxido de Silício/química , Polímeros/química , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Porosidade , Células MCF-7 , Umbeliferonas/química , Umbeliferonas/farmacologia , Portadores de Fármacos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos
3.
Gene ; 911: 148357, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462023

RESUMO

PURPOSE: The most common malignancy among women worldwide is breast cancer. The estrogen receptor plays a vital role in this cancer. One of the most well-known mechanisms that affects the activity of this receptor is its phosphorylation by protein kinase pathways. Hesperetin, a flavonoid abundant in citrus species such as lemons, grapefruits, and oranges, is the aglycone form of hesperidin. It has undergone thorough evaluation for its potential anti-cancer properties, particularly in the context of breast cancer. Studies have shown that hesperetin has an effect on intracellular kinase pathways. The aim of this study was to investigate the effect of hesperetin on the expression, phosphorylation and activity of estrogen receptor alpha (ERα) in MCF-7 breast cancer cell line. STUDY DESIGN AND METHODS: MCF-7 cells were cultured in RPMI-1640 phenol red-free medium supplemented with charcoal-stripped FBS and treated with hesperetin. The MTT method was used to evaluate cell survival. The levels of the ERα protein and its phosphorylated form (Ser118) were determined via western blotting. A luciferase reporter vector was used to evaluate ERE activity. RESULTS: The results of this study indicated that hesperetin reduced the survival of MCF-7 cells in a dose-dependent manner. The expression and phosphorylation (at Ser118) of the ERα significantly increased and decreased, respectively, in the groups treated with hesperetin. Hesperetin increased the activity of the ERα in the absence of E2, although these differences were not statistically significant. Conversely, in the presence of E2, hesperetin caused a significant decrease in receptor activity. CONCLUSION: Based on the results of this study, it can be concluded that hesperetin has a significant effect on ERα expression, phosphorylation and activity.


Assuntos
Neoplasias da Mama , Hesperidina , Feminino , Humanos , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Células MCF-7 , Hesperidina/farmacologia , Fosforilação , Estradiol , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células
4.
J Biomol Struct Dyn ; : 1-21, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345131

RESUMO

The main purpose of this research was to evaluate the role of α-lactalbumin (α-LA), ß-lactoglobulin (ß-LG), and ß-Caseins (ß-CN) in the binding interaction between Nano Resveratrol (Nano Res), as binary and ternary systems. This investigation was fulfilled through the application of multi-spectroscopic, transmission electron microscopy (TEM), field emission scanning electron microscope (FE-SEM), conductometry, isothermal titration calorimetry (ITC), and molecular dynamics (MD) simulation techniques. Fluorescence spectroscopy observations illustrated the effectiveness of Nano Res throughout the quenching of α-LA, (α-LA-ß-LG), and (α-LA-ß-CN) complexes, confirming the occurrence of interaction through the combination of static and dynamic mechanisms. An enhancement in the temperature of all three complexes caused a decrease in their Ksv and Kb values, which indicates the static and dynamic behavior of their interactions. The obtained thermodynamic parameters proved the dominance of electrostatic interaction as the binding force of both binary and ternary systems. The observed properties of Tyr or Trp residues in proteins through the data of synchronous spectroscopy at Δλ = 15 and 60 nm, respectively, demonstrated the closer positioning of (α-LA-ß-CN) complex to the proximity of Trp residues when compared to the two other cases. According to the resonance light scattering (RLS) measurements, the detection of a much greater RLS intensity in (α-LA-ß-CN) Nano Res complex suggested the production of a larger complex. Furthermore, the conductometry outcomes displayed an increase in molar conductivity and therefore approved the occurrence of interaction between Nano Res and proteins in both binary and ternary systems. The spherical shape of Nano Res was confirmed through the results of FE-SEM and TEM analyses. The conformational changes of proteins throughout the binding of Nano Res was evaluated by circular dichroism (CD) technique, while molecular docking and MD simulations affirmed the binding of Nano Res to α-LA, (α-LA-ß-LG), and (α-LA-ß-CN) complexes as binary and ternary systems. These In Silico study data confirm the results of in vitro assessments. The occurrence of changes in the secondary structure of ß-galactosidase was implied through the increased enzyme catalytic activity induced by the interaction of different lactose concentrations.Communicated by Ramaswamy H. Sarma.

5.
Bioprocess Biosyst Eng ; 46(11): 1569-1578, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37700115

RESUMO

Cerium oxide nanoparticles (CeO2-NPs) and Zn-Ni dual-doped CeO2-NPs were synthesized through a green approach by the implication of zucchini peel (Cucurbita pepo) extract as a capping and reduction agent. All the synthesized samples were studied by the results of FTIR, UV-Vis, XRD, and FESEM/EDAX/PSA analyses. The Zn-Ni dual-doped CeO2-NPs contained a spherical morphology and their size was observed to increase at higher temperatures. The conducted MTT assay on the Huh-7 cell line displayed 50% of cells annihilation as a result of using undoped CeO2-NPs and Zn-Ni dual-doped CeO2-NPs at the inhibitory concentrations (IC50) of 700 and 185.4 µg/mL, respectively. We also evaluated the enzymatic functionality of SOD and CAT of undoped CeO2-NPs and dual-doped NPs and found it to be dose dependent. Moreover, Zn-Ni dual-doped CeO2-NPs intensified the CAT activity without causing any changes in SOD activity in similar concentrations.


Assuntos
Cério , Nanopartículas Metálicas , Nanopartículas , Óxido de Zinco , Antioxidantes/farmacologia , Zinco , Níquel , Cério/farmacologia , Superóxido Dismutase
6.
Bioprocess Biosyst Eng ; 46(8): 1163-1173, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37326639

RESUMO

The aim of this study is the green synthesis of cerium oxide nanoparticles (CeO2-NPs) using a natural capping agent and its application in water and wastewater treatment. This study presents the biosynthesis of CeO2-NPs by the exertion of a green method using zucchini (Cucurbita pepo) extract as a capping agent. Synthesized CeO2-NPs were distinguished through TGA/DTA, FT-IR, XRD, FESEM/TEM and EDX/PSA, and DRS procedures. According to the XRD pattern of NPs, the crystallinity structure was a face-centered cubic (fcc) with an Fm3m space group and the size was estimated at 30 nm. The spherical morphology of NPs was confirmed through FESEM/TEM images. In the following, the photocatalytic property of NPs was investigated by the decolorization of methylene blue (MB) dye within UV-A light. Also, the cytotoxicity of NPs on the CT26 cell line was evaluated through the MTT test, and no toxicity was observed in the results, which indicates their biocompatibility.


Assuntos
Cério , Nanopartículas Metálicas , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/química , Nanopartículas/química , Cério/química , Extratos Vegetais/química , Nanopartículas Metálicas/química
7.
J Trace Elem Med Biol ; 78: 127186, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148696

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive kind of malignant primary brain tumor in humans. Given the limitation of Conventional therapeutic strategy, the development of nanotechnology and natural product therapy seems to be an effective method enhancing the prognosis of GBM patients. In this research, cell viability, mRNA expressions of various apoptosis-related genes apoptosis, and generation of reactive oxygen species (ROS) in human U-87 malignant GBM cell line (U87) treated with Urolithin B (UB) and CeO2-UB. Unlike CeO2-NPs, both UB and CeO2-UB caused a dose-dependent decrease in the viability of U87 cells. The half-maximal inhibitory concentration values of UB and CeO2-UB were 315 and 250 µM after 24 h, respectively. Moreover, CeO2-UB exerted significantly higher effects on U87 viability, P53 expression, and ROS generation. Furthermore, UB and CeO2-UB increased the accumulation of U87 cells in the SUB-G1 population, decreased the expression of cyclin D1, and increased the Bax/Bcl2 ratio expression. Collectively, these data indicate that CeO2-UB exhibited more substantial anti-GBM effects than UB. Although further in vivo investigations are needed, these results proposed that CeO2-NPs could be utilized as a potential novel anti-GBM agent after further studies.


Assuntos
Glioblastoma , Nanopartículas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Glioblastoma/tratamento farmacológico
8.
J Biomol Struct Dyn ; 41(3): 778-791, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34919017

RESUMO

The current study produced Quercetin nanoemulsions (QuNEs) for the purpose of improving Quercetin solubility in an aqueous polar condition and to analyze QuNE-protein formation (QuNE-human serum albumin (HSA) and QuNE-holo-transferrin (HTF)).QuNE was produced by utilizing an ultrasound-based emulsification method and was characterized by DLS, TEM, and SEM. Its interaction with HSA and HTF proteins was studied by analyzing the results of FRET and RLS spectroscopy, Stern-Volmer plotting, the Van't Hoff equation, CD spectroscopy, and molecular docking methods. Finally, QuNE's cytotoxic impact, cell death type induction, and antioxidant properties were evaluated by applying an MTT assay on a human hepatocyte cancer cell (HepG2), measuring Cas-3 gene expression, and conducting a DPPH antioxidant test, respectively. Compared to the non-entrapped Quercetin, Quercetin-entrapped nano-emulsions formed stable complexes with HSA and HTF by improving hydrophilic-hydrophobic interactions. The binding constant (BC), ΔH0, and ΔS0 indices for both the QuNE-HSA and QuNE-HTF complexes were measured at (4.92 × 105 and 11.99 × 104 M-1), (170.96 and -131.19 KJ.mol-1), and (-464.86 and 342.83J.mol-1K-1), respectively.QuNE lowered the HepG2 viability by up-regulating Cas-3 gene expression and thus inducing apoptosis. Moreover, a notable antioxidant impact on the QuNE was detected. Due to its ability in delivering Quercetin to HSA and HTF proteins and stabilizing their protein complexes, QuNE can be used as a suitable primary transporting agent whose formation of stable bio-accessible QuNE-HSA and -HTF protein complexes creates a safe and natural secondary delivery system, which has potential to be used as an efficient anticancer compound.Communicated by Ramaswamy H. Sarma.


Assuntos
Quercetina , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/metabolismo , Quercetina/farmacologia , Azeite de Oliva , Simulação de Acoplamento Molecular , Transferrina/química , Antioxidantes/farmacologia , Ligação Proteica , Proteínas Sanguíneas/metabolismo , Termodinâmica , Dicroísmo Circular , Espectrometria de Fluorescência/métodos , Sítios de Ligação
9.
Gastroenterol Hepatol Bed Bench ; 15(2): 131-138, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845310

RESUMO

Aim: The present study aimed to evaluate the expression profile, prognostic value, and possible correlation of TRIM29 with ß-catenin, Cyclin D, and Bcl2 in Iranian patients with GC. Background: Tripartite Motif Containing 29 (TRIM29) has been reported to function as an oncogene or a tumor suppressor depending on the tumor type. This contextual function has created a controversial situation that needs to be fully delineated in various cancers. Although few studies have reported an elevated TRIM29 expression in gastric cancer (GC), its clinicopathological and prognostic values as well as possible molecular mechanisms are yet to be re-evaluated in different populations. Methods: Real-time quantitative PCR was used to detect TRIM29, ß-catenin, Cyclin D, and Bcl-2 expression in 40 GC and their adjacent normal tissues. Patients were further stratified into high and low expression subgroups based on their TRIM29 expression levels. The association of TRIM29 expression level with ß-catenin, Cyclin D, BCL2, some clinicopathological features, and patients' overall survival (OS) was assessed using appropriate statistical analyses. Results: The results showed a significantly higher TRIM29 expression level in GC tissues compared with their corresponding normal tissues (fold change=2.94, p=0.003). Patients with high TRIM29 expression levels exhibited poorer OS (HR=1.25, 95% CI: 1.06-1.47, p=0.007). High expression of TRIM29 was also associated with increased levels of ß-catenin, Cyclin D, and Bcl-2 genes expression. Conclusion: Overexpression of TRIM29 is associated with poor prognosis in patients with GC and is probably mediated through ß-catenin/Cyclin D/Bcl2 pathway and can be considered as a potential independent prognostic marker.

10.
J Clin Neurosci ; 101: 57-62, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35533613

RESUMO

BACKGROUND: Methadone and buprenorphine which are widely used for opioid maintenance treatment can affect redox status and also brain functions. The present study aimed to compare inflammation, oxidative stress, and cognitive function in methadone maintenance patients (MMP), buprenorphine maintenance patients (BMP), and healthy participants. METHOD: Oxidative- antioxidant markers, inflammatory factors were investigated in MMP (n = 30), BMP (n = 30), and healthy participants (n = 30) by evaluating the ferritin, malondialdehyde (MDA), total antioxidant capacity (TAC), and also High-sensitivity C-reactive protein (hs-CRP). Also, executive function was evaluated using Wisconsin Card Sorting Test (WCST). FINDINGS: MMP and BMP showed impairment in executive function compared to the healthy participants. Both buprenorphine and methadone treatments induced oxidative stress. The ferritin level in BMP was significantly lower compared to MMP and healthy participants (P = 0.01). There was a significant difference between control and MMP and BMP (P > 0.0001) in terms of hs-CRP level. BMP had the highest and healthy participant's lowest MDA level (P < 0.001). The TAC levels in BMP were lower than in MMP (p = 0.002) and healthy participants (p = 0.001). Finally, executive function was significantly correlated with oxidative-antioxidant status. DISCUSSION: Both methadone and buprenorphine induced severe oxidative activity (especially buprenorphine) and cognitive deficits compared to healthy participants. Stress oxidative can affect normal brain activity and consequently cognitive functions. It's suggested that concomitant antioxidant administration with buprenorphine or methadone can potentially enhance their beneficial action by regulating blood redox status.


Assuntos
Buprenorfina , Humanos , Analgésicos Opioides/uso terapêutico , Antioxidantes , Buprenorfina/farmacologia , Buprenorfina/uso terapêutico , Proteína C-Reativa , Cognição , Ferritinas , Voluntários Saudáveis , Metadona/uso terapêutico , Estresse Oxidativo
11.
Int J Biol Macromol ; 211: 700-710, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35588975

RESUMO

Cell-laden filament-like hydrogels are advantageous for many applications including drug screening, tissue engineering, and regenerative medicine. However, most of the designed filament vehicles hold weak mechanical properties, which hinder their applications in specific tissue engineering. We present a binary hybrid silk and hyaluronic acid hydrogel microfiber generated through a microfluidic system to encapsulate cells with superior mechanical properties and biocompatibility. Cell-laden hydrogel microfibers were continuously produced through coaxial double orifice microfluidic device and horseradish peroxidase mediated crosslinking, which conjugated introduce phenolic moieties in the backbone of silk fibroin and HA derivatives (Silk-Ph and HA-Ph, respectively). The iterative hybrid Silk-Ph + HA-Ph fibers were fabricated in tunable size distribution between 195 and 680 µm through control of outer flow velocity. Tensile strength and maximum stain of prepared Silk-Ph + HA-Ph sample upregulated more than three times higher than the single HA-Ph sample, which demonstrated significant impacts of synthesized silk derivative in hydrogel fiber composition. The proteolytic degradation of microfibers manipulated by hyaluronidase and collagenase treatment. Encapsulation process and crosslinking did not insert any harmful effect on cell viability (> 90%) and the cells maintained their growth ability after encapsulation process. Cellular filament-like tissue fabricated from proliferation of cells in Silk-Ph + HA-Ph microfiber.


Assuntos
Fibroínas , Seda , Ácido Hialurônico/química , Hidrogéis/química , Engenharia Tecidual , Regulação para Cima
12.
J Gastrointest Cancer ; 53(1): 179-186, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33415720

RESUMO

BACKGROUND/AIMS: Tripartite motif-containing 3 (TRIM3) is a member of the TRIM protein family which is known to be involved in development of numerous tumor types. However, the prognostic role of TRIM3 in gastric cancer (GC) remained to be clarified. The aim of this study was to evaluate the expression pattern and prognostic significance of TRIM3 gene and its relationship with ß-catenin, CyclinD, and BCL2 expression in patients with GC. METHODS: A total of 40 fresh primary gastric cancer tumors and their matched adjacent noncancerous tissues were selected from the First Affiliated Hospital of Mashhad University. Real-time quantitative RT-PCR was performed to evaluate differences in TRIM3 expression in GC and normal tissues. The correlation between TRIM3 expression level and patients' overall survival, some clinicopathological variables, and ß-catenin, CyclinD, and BCL-2 genes expression level were also studied. Moreover, patients were divided in two groups according to the TRIM3 expression levels: low and high. RESULTS: Compared to noncancerous tissues, TRIM3 expression in GC tissues was significantly increased (fold change = 1.58). Kaplan-Meier survival analysis revealed a significant difference of patient survival according to TRIM3 expression status (P = 0.012). Low TRIM3 expression was associated with shorter overall survival and was an independent predictor for poor prognosis in GC patients (HR, 1.25; 95%CI, 1.02-1.60; P = 0.045). Expression of TRIM3 was negatively correlated with expression of ß-catenin, BCL-2, and CyclinD as genes for proliferation, apoptosis, and the cell cycle in GC patients. CONCLUSIONS: This study demonstrates that decreased level of TRIM3 mRNA expression is associated with poor prognosis in patients with gastric cancer. TRIM3 may play a protective role in gastric cancer by relieving the effects of cancer progressive genes and could be considered for further investigations as a prognostic biomarker.


Assuntos
Neoplasias Gástricas , Apoptose , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Ciclo Celular , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Neoplasias Gástricas/patologia
13.
J Mol Model ; 27(2): 40, 2021 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-33454889

RESUMO

O6-methylguanine DNA methyl transferase (MGMT) is a metalloenzyme participating in the repair of alkylated DNA. In this research, we performed a comparative study for evaluating the impact of zinc metal ion on the behavior and interactions of MGMT in the both enzymatic forms of apo MGMT and holo MGMT. DNA and proliferating cell nuclear antigen (PCNA), as partners of MGMT, were utilized to evaluate molecular interactions by virtual microscopy of molecular dynamics simulation. The stability and conformational alterations of each forms (apo and holo) MGMT-PCNA, and (apo and holo) MGMT-DNA complexes were calculated by MM/PBSA method. A total of seven systems including apo MGMT, holo MGMT, free PCNA, apo MGMT-PCNA, holo MGMT-PCNA, apo MGMT-DNA, and holo MGMT-DNA complexes were simulated. In this study, we found that holo MGMT was more stable and had better folding and functional properties than that of apo MGMT. Simulation analysis of (apo and holo) MGMT-PCNA complexes displayed that the sequences of the amino acids involved in the interactions were different in the two forms of MGMT. The important amino acids of holo MGMT involved in its interaction with PCNA included E92, K101, A119, G122, N123, P124, and K125, whereas the important amino acids of apo MGMT included R128, R135, S152, N157, Y158, and L162. Virtual microscopy of molecular dynamics simulation showed that the R128 and its surrounding residues were important amino acids involved in the interaction of holo MGMT with DNA that was exactly consistent with X-ray crystallography structure. In the apo form of the protein, the N157 and its surrounding residues were important amino acids involved in the interaction with DNA. The binding free energies of - 387.976, - 396.226, - 622.227, and - 617.333 kcal/mol were obtained for holo MGMT-PCNA, apo MGMT-PCNA, holo MGMT-DNA, and apo MGMT-DNA complexes, respectively. The principle result of this research was that the area of molecular interactions differed between the two states of MGMT. Therefore, in investigations of metalloproteins, the metal ion must be preserved in their structures. Finally, it is recommended to use the holo form of metalloproteins in in vitro and in silico researches.

14.
RSC Adv ; 11(59): 37103-37111, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35496431

RESUMO

The transmutation of waste into valuable materials has a special place in green chemistry. Herein, we report the preparation of quinazoline-2,4(1H,3H)-diones from 2-iodoaniline, isocyanides, and carbon dioxide in the presence of ZnO NPs stably placed on the surface of dendritic fibrous nanosilica by cellulose (DFNS/cellulose-ZnO) as a catalyst. This is a great economic strategy to create three bonds in a one-pot multicomponent reaction step employing functional groups. To prepare the catalyst, the dendritic fibrous nanosilica surface was first activated using cellulose as a substrate to support ZnO NPs. Cellulose acts as a stabilizing and reducing agent for the ZnO nanocatalyst and eliminates the need for a reducing agent. The structure of the prepared DFNS/cellulose-ZnO was examined by various methods, including thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma (ICP). The largest amount of quinazoline-2,4(1H,3H)-diones was obtained under ideal situations in the presence of 5 mg of DFNS/cellulose-ZnO under carbon dioxide (1 atm) utilizing a balloon set at 70 °C for 3 hours. The substance was reused for ten consecutive runs and the quinazoline-2,4(1H,3H)-dione content was more than 92% each time. This indicates the potential for application in the green and economic production of quinazoline-2,4(1H,3H)-diones, especially from low-cost feedstocks.

15.
RSC Adv ; 11(42): 26174-26187, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35479476

RESUMO

Sulfated zirconium oxide (ZrO2/SO4 2-) as a highly durable acidic reagent was immobilized on magnetite KCC-1 nanoparticles (Fe3O4@SiO2/KCC-1@ZrO2/SO4 2- NPs), and the resulting hybrid was used as a highly efficient recyclable adsorbent for the adsorption and removal of asphaltene from crude oil. The presence of ZrO2/SO4 2- groups not only promotes the adsorption capacity, but also helps recycle the adsorbents without any significant efficiency loss arising from its high chemical resistance. The results showed an obvious synergistic effect between the magnetic core (Fe3O4 NPs), fibrous silica (KCC-1) and the sulfated zirconium oxide groups with high correlation for asphaltene adsorption. The effective parameters in asphaltene adsorption, including initial asphaltene concentration, catalyst concentration and temperature, were investigated. Maximum adsorption occurred in the presence of 0.7 g L-1 of the adsorbent, at a concentration of 2000 mg L-1 of asphaltene. The asphaltene adsorption by NPs follows a quasi-second order adsorption kinetics. Asphaltene adsorption kinetics were studied by Langmuir, Freundlich, and Temkin isotherms. The prominent advantage of the adsorbent is its ability to be recovered after each adsorption by acid treatment, so that no significant reduction in adsorbent adsorption activity was observed, which can be directly attributed to the presence of ZrO2/SO4 2- groups in the hybrid.

16.
RSC Adv ; 10(26): 15044-15051, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35495475

RESUMO

We studied the potential application of an efficient, reusable, and easily recoverable catalyst of dendritic fibrous nanosilica (DFNS)-supported platinum(ii) complexes (DFNS/Pt(ii) NPs) to form cyclic carbonates in the presence of epoxides by converting carbon dioxide. Cyclic carbonates from epoxides and carbon dioxide is proposed as the most appropriate way to synthesis this C1 building block. We performed FE-SEM, TEM, TGA, BET, VSM, and ICP-MS to thoroughly characterize DFNS/Pt(ii) NPs.

17.
RSC Adv ; 10(46): 27297-27304, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35516956

RESUMO

Water is an essential substance for life on earth and for all living things. Plants and animals need almost pure water to live; if it is contaminated with harmful chemicals and micro organisms, it will be impossible for them to survive. This study has tried to investigate the performance of catalyst to reduce nitro-aromatic combinations in the attendance of NaBH4 solution duo to the hydrogen source. TEMPO@FeNi3/DFNS-laccase MNPs was prepared, and its features were reviewed using SEM, TEM, XRD, TGA, VSM, AFM, and FTIR. Then, its strength as a nanocatalyst for removal of nitro-aromatic combinations was tested in contact time, initial concentration, the effects of pH and nanocatalyst amount was study. The results of this research proved that TEMPO@FeNi3/DFNS-laccase MNPs has a good return in removal of nitro-aromatic combinations, as its easy synthesis and reliable recovery.

18.
RSC Adv ; 10(35): 20536-20542, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35517733

RESUMO

For aerobic oxidation, anchoring ruthenium(ii) in the nanospaces of magnetic dendritic fibrous nanosilica (DFNS) afforded a potential nanocatalyst (the complex FeNi3/DFNS/Ru(ii)), which showed enhanced activity. The FeNi3/DFNS/Ru(ii) complex exhibited excellent catalytic activity in the reduction of carbon dioxide to formate in the presence of visible-light irradiation. We have analyzed its characteristics by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA).

19.
RSC Adv ; 9(60): 35022-35032, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35530702

RESUMO

Herein, Cu(ii) complexes were anchored within the nanospaces of a magnetic fibrous silicate with a high surface area and easily accessible active sites via a facile approach, leading to the successful synthesis of a novel potent nanocatalyst (FeNi3/DFNS/Cu). Furthermore, FeNi3/DFNS/Cu was supported on carbon nanotubes (CNTs) via an usual nozzle electrospinning method (CNT-FeNi3/DFNS/Cu). In addition, its performance as a photocatalyst for the degradation of tetracycline was tested in a batch reactor. Tetracycline is an antibiotic that is commonly utilized in veterinary medicine and in the treatment of human infections, but is hazardous to aquatic environments. However, the usual processes for the removal of tetracycline are not efficient. The eco-friendly attributes of this catalytic system include high catalytic activity and ease of recovery from the reaction mixture using an external magnet, and it can be reused several times without significant loss in its performance. Also, protocols such as hot filtration, and mercury poisoning provided complete insight into the nature of this heterogeneous catalyst.

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