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Mesoporous silica nanocarriers as accommodate drug molecule capsules were synthesized and capped by chitosan natural polymer. This nanocarrier acts as a pH-responsive shield to increase the solubility and improvement of anticancer properties of curcumin against U87MG glioblastoma cancer cell line. The encapsulation efficiency and drug-loading content were measured 88.1 ± 4.76% and 8.81 ± 0.47%, respectively. The curcumin release from the CS-MCM-41 was slow and sustained at low pH (42.72 ± 2.29%) compared to the environment pH (19.54 ± 1.36%) in 96 h. The MTT evaluations showed that IC after 72 h treatment with free curcumin and curcumin-loaded CS-MCM-41 were 15.20 and 5.21 μg/mL (p <0.05). respectively.

Surface modification of Fe3O4 nanoparticles was performed by immobilizing silica, metformine, and amine. Mixed matrix PES nanofiltration membrane was prepared by embedding various concentrations of the modified Fe3O4 based nanoparticles. The membranes were characterized in terms of morphology and performance including investigation of SEM and AFM microphotographs, water contact angle, mean pore size and porosity measurements and determination of pure water flux as well as copper ion removal. Embedding iron oxide nanoparticles resulted in a significant rise in the pure water flux as a result of changes in the mean pore radius, porosity and hydrophilicity of the membranes. Moreover, the copper removal capability of prepared membranes remarkably increased because of improved hydrophilicity and also presence of nucleophilic functional groups on nanoparticles. The membrane fabricated with 0.1 wt.% metformine-modified silica coated Fe3O4 nanoparticles showed the highest copper removal (about 92%) due to high affinity in copper adsorption. Moreover, acceptable reusability was found for the membrane with the best performance after several times of usage/regeneration cycles usin EDTA as eluting agent.

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A novel biguanide-functionalized Fe 3 O 4 /SiO 2 magnetite nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperbase in chemical transformations. The structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (TEM), powder X-ray diffraction (XRD), vibrating sample magnetometry (VSM), elemental analyzer (EA), thermogravimetric analysis (TGA), N 2 adsorption-desorption (BET and BJH) and FT-IR. The biguanide-functionalized Fe 3 O 4 /SiO 2 nanoparticles showed a superpara-magnetic property with a saturation magnetization value of 46.7 emu/g, indicating great potential for application in magnetically separation technologies. In application point of view, the prepared catalyst was found to act as an efficient recoverable nanocatalyst in nitroaldol and domino Knoevenagel condensation/Michael addition/cyclization reactions in aqueous media under mild condition. Additionally, the catalyst was reused six times without significant degradation in catalytic activity and performance.

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