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991.
Mojgan Ghanbari Masoud Salavati-Niasari Fatemeh Mohandes Banafsheh Dolatyar Bahman Zeynali 《RSC advances》2021,11(27):16688
Porous substrates composed of biodegradable polymers and nanoparticles have found extensive use as three-dimensional (3D) scaffolds to regenerate damaged tissues through the incorporation of cells or growth factors. Here, injectable thermally responsive hydrogels based on SiO2 nanoparticles (NPs), alginate, and gelatin biopolymers, with possible utilization for cartilage tissue engineering, are introduced. The nanocomposites contain different amounts of SiO2 NPs for reinforcement and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS) for chemical crosslinking of polymer chains in the 3D hydrogel network. The cross-sectional structure of the hydrogels containing 0.25, 1.5, and 3.0% SiO2 NPs was observed by FE-SEM, confirming porous morphology with interconnected pores. Based on the rheometer analyses, by increasing the amount of SiO2 NPs, the mechanical strength of the gels can be found. In addition, in vitro biodegradation studies show that the hydrogels without SiO2 are more unstable than the hydrogels containing SiO2 NPs. In vitro biocompatibility of the products tested by MTT assay indicates that cell viability and attachment depend on the presence of SiO2 NPs.Thermoresponsive oxidized alginate/gelatin/SiO2 NPs injectable hydrogels have great potential in cartilage tissue engineering due to low gelation time (120 s) and body temperature gelation (37 °C). 相似文献
992.
Mahdi Ranjeh Omid Amiri Masoud Salavati-Niasari Mehdi Shabani-Nooshabadi 《RSC advances》2021,11(38):23430
The nanocomposites of LiCoO2/Fe3O4/Li2B2O4 were designed by the Pechini route using different fuels for the optimization of their morphology and structure. Compared to other fuels, citric acid can act as both an ideal fuel and a capping agent. The ratio of the EG : H2O mixture is another parameter, which was studied in terms of its effects on the structural characterization. The optimized sample with a rod shape was selected to compare with the bulk sample through electrochemical hydrogen storage capacity. The discharge capacity for rod-shaped nanocomposites measured was 1284 mA h g−1. However, the discharge capacity for the bulk morphology was calculated to be about 694 mA h g−1. The magnetic, electrochemical and structural analyses were performed to investigate the properties of LiCoO2/Fe3O4/Li2B2O4 nanocomposites.To the best of our knowledge, for the first time, the effects of LiCoO2/Fe3O4/Li2B2O4 nanocomposites as a favorable hydrogen capacitor were investigated to enhance hydrogen storage performance. 相似文献
993.
Elham Abkar Mohammad Hassanpour Omid Amiri Mojgan Ghanbari Masoud Salavati-Niasari 《RSC advances》2021,11(36):22238
Efforts to find new and practical solutions to improve water quality and treatment of industrial effluents are ongoing. In this study, Tl4HgI6/HgI2 nanocomposites were synthesized by a rapid ultrasonic method to investigate their photocatalytic and antibacterial activity. Various synthesis conditions such as changes in the ratio of precursors, use of surfactants, and changes in the power and time of sonication to achieve particles with optimal size and morphology were performed. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) analysis confirmed the purity and formation of the nanocomposite. Optimal nanoparticles in terms of size and morphology were selected by examining the images obtained from scanning electron microscopy (SEM) analysis. The nanocomposites obtained in the presence of PVP (polyvinylpyrrolidone) as a surfactant (sample no. 8) were selected as the optimal sample. Transmission electron microscopy (TEM), differential reflectance spectroscopy (DRS), Raman, N2 adsorption/desorption analyzes were performed for the optimal sample to evaluate the properties of nanocomposites. The band-gap for Tl4HgI6/HgI2 nanocomposites was calculated to be about 2.3 eV for HgI2 and 3.1 eV for Tl4HgI6. The optimal sample was used to evaluate the photocatalytic activity for decolorizing an aqueous solution of six different organic dyes. Finally, for rhodamine B, the decolorization was about 80%. Also, Tl4HgI6/HgI2 nanocomposite showed a significant inhibition zone in the antibacterial test. The maximum inhibition diameter of 50 mm was obtained against Streptococcus pyogenes. The results showed that Tl4HgI6/HgI2 nanocomposites have good potential for many industrial applications.In this work, Tl4HgI6/HgI2 nanocomposites were synthesized by a rapid ultrasonic method. The photocatalytic properties of the nanocomposites were evaluated for the first time. Photocatalytic properties were performed for six industrial dyes. 相似文献
994.
Jamshaid Ashraf Ehsan Ullah Mughal Reem I. Alsantali Amina Sadiq Rabab. S. Jassas Nafeesa Naeem Zaman Ashraf Yasir Nazir Muhammad Naveed Zafar Amara Mumtaz Masoud Mirzaei Satar Saberi Saleh A. Ahmed 《RSC advances》2021,11(56):35077
The excelling role of organic chemistry in the medicinal field continues to be one of the main leads in the drug development process. Particularly, this industry requires organic chemists to discover small molecular structures with powerful pharmacological potential. Herein, a diverse range of chalcone (1–11) and aurone (12–22) derivatives was designed and synthesized and for the first time, and both motifs were evaluated as potent inhibitors of alkaline phosphatases (APs). Structural identification of the target compounds (1–22) was accomplished using common spectroscopic techniques. The effect of the nature and position of the substituent was interestingly observed and justified based on the detailed structure–activity relationship (SAR) of the target compounds against AP. It was concluded from the obtained results that all the newly synthesized compounds exhibit high inhibitory potential against the AP enzyme. Among them, compounds 12 (IC50 = 2.163 ± 0.048 μM), 15 (IC50 = 2.146 ± 0.056 μM), 16 (IC50 = 2.132 ± 0.034 μM), 18 (IC50 = 1.154 ± 0.043 μM), 20 (IC50 = 1.055 ± 0.029 μM) and 21 (IC50 = 2.326 ± 0.059 μM) exhibited excellent inhibitory activity against AP, and even better/more active than KH2PO4 (standard) (IC50 = 2.80 ± 0.065 μM). Remarkably, compound 20 (IC50 = 1.055 ± 0.029 μM) may serve as a lead structure to design more potent inhibitors of alkaline phosphatase. To the best of our knowledge, these synthetic compounds are the most potent AP inhibitors with minimum IC50 values reported to date. Furthermore, a molecular modeling study was performed against the AP enzyme (1EW2) to check the binding interaction of the synthesized compounds 1–22 against the target protein. The Lineweaver–Burk plots demonstrated that most potential derivative 20 inhibited h-IAP via a non-competitive pathway. Finally, molecular dynamic (MD) simulations were performed to evaluate the dynamic behavior, stability of the protein–ligand complex, and binding affinity of the compounds, resulting in the identification of compound 20 as a potential inhibitor of AP. Accordingly, excellent correlation was observed between the experimental and theoretical results. The pharmacological studies revealed that the synthesized analogs 1–22 obey Lipinski''s rule. The assessment of the ADMET parameters showed that these compounds possess considerable lead-like characteristics with low toxicity and can serve as templates in drug design.Aurones are the plant secondary metabolites belonging to the flavonoid’s family. The bioactivities of aurones are very promising, thus these heterocyclic compounds can be considered as an alluring scaffold for drug design and development. 相似文献
995.
In this study, NiFe2O4–PEG, an effective nanocatalyst was synthesized via a hydrothermal method using different PEG concentrations and synthesis times. The synthesized nanocatalyst was used in the ultrasound assisted oxidative desulfurization (UAOD) of model fuels (e.g. n-hexane and dibenzothiophene (DBT)) for the first time. The nanocatalyst was then characterized by XRD, FTIR, BET, SEM, VSM and TEM analyses. In addition, central composite design was used to evaluate the effective variables on the UAOD process. The optimal values of effective factors such as catalyst dose, oxidant amount, irradiation time and ultrasonic power to maximize of the percentage of sulfur removal were 0.149 g, 15 mL, 11.96 min, and 70 MHz, respectively. Moreover, the kinetic aspects of the oxidation reaction of DBT in the UAOD process were investigated using a pseudo-first-order model. Furthermore, using the Arrhenius equation, an activation energy of 35.86 kJ mol−1 was obtained. Additionally, thermodynamic analysis showed that the oxidation reaction of DBT was endothermic with a positive Gibbs free of energy, indicating the non-spontaneity of oxidation of DBT in the UAOD process. Moreover, the conversion rate of DBT has increased from 57% at 35 °C to 85% at 65 °C.In this study, NiFe2O4–PEG, an effective nanocatalyst was synthesized via a hydrothermal method using different PEG concentrations and synthesis times. 相似文献
996.
Hybrid injectable and biodegradable hydrogels based on oxidized alginate/gelatin and containing nitrogen-doped carbon dots (NCDs) as a reinforcement have been fabricated and crosslinked by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) as the chemical crosslinking agents in the hydrogel system. The idea of composite hydrogels relies on the assumption that they supply a microenvironment that is convenient for the exchange of nutrients via a porous structure and cell proliferation and have mechanical characteristics that approximately match natural tissue. The effect of the NCD content on the morphology structure, mechanical strength, swelling ratio, and biodegradation has been investigated. The results indicate that nanocomposite hydrogels containing a higher content of NCDs have smaller pore sizes and higher mechanical properties. The in vitro biodegradation and swelling behavior demonstrated that increasing the amount of NCDs up to 0.06% decreased the swelling ratio and weight loss of the hydrogels. The composite hydrogels are biocompatible, as verified by the MTT assay of MG-63 cells. The N-doped graphene quantum dots considerably affect degradation and interaction within the cells and hydrogels.The low gelation time (120 s) and gelation temperature at body temperature (37 °C) make oxidized alginate/gelatin/NCDs hydrogels suitable as temperature-sensitive injectable hydrogels for cartilage tissue engineering. 相似文献
997.
Seyed Milad Tabatabaeinejad Sahar Zinatloo-Ajabshir Omid Amiri Masoud Salavati-Niasari 《RSC advances》2021,11(63):40100
Designing and fabricating an efficient photocatalytic compound with an appropriate band gap to eliminate toxic contaminants is necessary to remediate the environment. This article presents the development of a new type of nanostructure, Lu2Cu2O5–Lu2O3 nanocomposites to photo-catalytically degrade different kinds of toxic pollutants under sunlight. The oxide nanocomposites were fabricated via a quick and eco-friendly approach. In order to fabricate oxide nanostructures with appropriate features in terms of morphology and particle size, the effects of the kind of green reactant and its quantity were examined. Amylum was an appropriate and green reactant for the efficient synthesis of Lu2Cu2O5–Lu2O3 nanobundles with the most organized morphology. The features of Lu2Cu2O5-based nanostructures were carefully investigated utilizing multiple characterization methods. Then, the catalytic role of the fabricated nanobundles was evaluated for the removal of various kinds of toxic contaminants. The effects of the quantity of photocatalytic nanostructure, the concentration of the contaminant compound, and the type of light source in the catalytic degradation process were screened. The findings of this research demonstrated that utilizing 0.05 g of Lu2Cu2O5–Lu2O3 nanobundles, 98.5% of the contaminant with a concentration of 10 ppm can be degraded in 2 h under ultraviolet light irradiation. The experimental results also certified that, during the photocatalytic pathway, superoxide radicals play a meaningful role in the elimination of toxic pollutants. To our knowledge, this is the first report of the fabrication of Lu2Cu2O5–Lu2O3 nanocomposite through a facile and eco-friendly approach and its photocatalytic efficiency.The synthesis of Lu2Cu2O5–Lu2O3 nanocomposites via a simple auto-combustion approach and their excellent performance in the removal of organic pollutants under sunlight is presented for the first time. 相似文献
998.
Kota Ogura Clment Brasselet Gustavo Cabrera-Barjas Masoud Hamidi Amin Shavandi Marguerite Dols-Lafargue Naoki Sawamura Cdric Delattre 《Materials》2022,15(4)
In this present work, fungal nanochitosans, with very interesting particle size distribution of 22 µm, were efficiently generated in high-yield production using a high-pressure water jet system (Star Burst System, Sugino, Japan) after 10 passes of mechanical treatment under high pressure. The specific characterization of fungal chitosan nanofibers suspensions in water revealed a high viscosity of 1450 mPa.s and an estimated transparency of 43.5% after 10 passes of fibrillation mechanical treatment. The mechanical characterization of fungal nanochitosan (NC) film are very interesting for medical applications with a Young’s modulus (E), a tensile strength (TS), and elongation at break (e%) estimated at 2950 MPa, 50.5 MPa, and 5.5%, respectively. Furthermore, we exhibited that the fungal nanochitosan (NC) film presented very good long-term antioxidant effect (reached 82.4% after 96 h of contact with DPPH radical solution) and very interesting antimicrobial activity when the nanochitosan (NC) fibers are mainly activated as NC-NH3+ form at the surface of the film with 45% reduction and 75% reduction observed for S. aureus (Gram-positive) and E. coli (Gram-negative), respectively, after 6 h of treatment. These promising antimicrobial and antioxidant activities indicated the high potential of valorization toward biomedical applications. 相似文献
999.
1000.
Masoud Nouri‐Vaskeh Aida Malek Mahdavi Hossein Afshan Leila Alizadeh Mohammad Zarei 《Phytotherapy research : PTR》2020,34(6):1446-1454
Recent reports indicated that curcumin had beneficial effects in animal models of liver injury and cirrhosis. Current study aimed to investigate the effects of curcumin supplementation in patients with liver cirrhosis. In this randomized double‐blind placebo‐controlled trial, 70 patients with liver cirrhosis aged 20–70 years were randomly divided into two groups to receive 1,000 mg/day curcumin (n = 35) or placebo (n = 35) for 3 months. Model for end‐stage liver disease (MELD) (i), MELD, MELD‐Na, and Child–Pugh scores were used to assess the severity of cirrhosis. Sixty patients (29 in the curcumin group and 31 in the placebo group) completed the study. MELD(i) (15.55 ± 3.78 to 12.41 ± 3.07), MELD (15.31 ± 3.07 to 12.03 ± 2.79), MELD‐Na (15.97 ± 4.02 to 13.55 ± 3.51), and Child–Pugh (7.17 ± 1.54 to 6.72 ± 1.31) scores decreased significantly in the curcumin group after 3‐month intervention (p < .001, p < .001, p = .001, and p = .051, respectively), whereas they increased significantly in the placebo group (p < .001, p < .001, p < .001, p = .001, respectively). Significant differences were only observed between the two groups in MELD(i), MELD, MELD‐Na, and Child–Pugh scores after 3‐month intervention (p < .001 for all of them). In this pilot study, beneficial effects of curcumin supplementation were observed in decreasing disease activity scores and severity of cirrhosis in patients with cirrhosis. 相似文献