saeed bahadorikhalili

Carbon-based materials. including carbon nanotubes, graphene, and activated carbon, are among the most effective materials for pharmaceutical components removal from water. Despite the severe effect of pharmaceutical micropollutants in the aquatic environments and the effectiveness of carbon-based composites for water treatment, only a few studies has reviewed carbon-based materials for the removal of pharmaceutical components. Carbon-based materials with special properties like tunable surface functions, abundant pore structure, and high specific surface are used in different water treatment mechanisms such as adsorption and advanced oxidation processes. Graphene, activated carbon, and carbon nanotubes have been widely studied for pharmaceutical components removal. Herein, we have introduced carbon-based materials and reviewed recent studies on their properties, application in water treatment, and possible mechanism for removal of pharmaceutical components from aquatic environments.

 Stimuli-responsive drug delivery systems have been proven to be a promising strategy to enhance tumor localization, overcome multidrug resistance (MDR), and reduce the side effects of chemotherapy agents.

 In this study, a temperature and redox dual stimuli-responsive system using mesoporous silica nanoparticles (MSNs) for targeted delivery of doxorubicin (DOX) was developed.

 Mesoporous silica nanoparticles were capped with poly(N-isopropylacrylamide) (PNIPAM), a thermo-sensitive polymer, with atom transfer radical polymerization (ATRP) method, via disulfide bonds (DOX-MSN-S-S-PNIPAM) to attain a controlled system that releases DOX under glutathione-rich (GSH-rich) environments and temperatures above PNIPAM’s lower critical solution temperature (LCST). Morphological and physicochemical properties of the nanoparticles were indicated using transmission electron microscopy (TEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Brunauer-Emmett-Teller (BET). The drug release tests were performed at 25°C and 41°C in the absence and presence of the DTT, and the obtained results confirmed the synergic effect of temperature and reductive agent on a dual responsive release profile with a 73% cumulative release at 41°C and reductive environment during 240 min.

 The average loaded drug content and encapsulation efficacy were reported as 42% and 29.5% at the drug: nanoparticle ratio of 1.5: 1. In vitro cytotoxicity assays on MCF-7 cell lines indicated significant viability decreased in cells exposed to DOX-MSN-S-S-PNIPAM compared to the free drug (DOX).

 Based on the results, DOX-MSN-S-S-PNIPAM has shown much more efficiency with stimuli-responsive properties in comparison to DOX on MCF-7 cancer cell lines.

Stimuli-responsive drug delivery systems have been proven to be a promising strategy to enhance tumor localization, overcome multidrug resistance (MDR), and reduce the side effects of chemotherapy agents.

In this study, a temperature and redox dual stimuli-responsive system using mesoporous silica nanoparticles (MSNs) for targeted delivery of doxorubicin (DOX) was developed.

Mesoporous silica nanoparticles were capped with poly(N-isopropylacrylamide) (PNIPAM), a thermo-sensitive polymer, with atom transfer radical polymerization (ATRP) method, via disulfide bonds (DOX-MSN-S-S-PNIPAM) to attain a controlled system that releases DOX under glutathione-rich (GSH-rich) environments and temperatures above PNIPAM’s lower critical solution temperature (LCST). Morphological and physicochemical properties of the nanoparticles were indicated using transmission electron microscopy (TEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and Brunauer-Emmett-Teller (BET). The drug release tests were performed at 25°C and 41°C in the absence and presence of the DTT, and the obtained results confirmed the synergic effect of temperature and reductive agent on a dual responsive release profile with a 73% cumulative release at 41°C and reductive environment during 240 min.

The average loaded drug content and encapsulation efficacy were reported as 42% and 29.5% at the drug: nanoparticle ratio of 1.5: 1. In vitro cytotoxicity assays on MCF-7 cell lines indicated significant viability decreased in cells exposed to DOX-MSN-SS-PNIPAM compared to the free drug (DOX).

Based on the results, DOX-MSN-S-S-PNIPAM has shown much more efficiency with stimuli-responsive properties in comparison to DOX on MCF-7 cancer cell lines.

Despite the extensive use of polyolefins, especially in the form of lithium-ion battery (LIB) separators, their flammability limits their large-scale battery applications. Therefore, the fabrication of flame-retardant LIB separators has attracted much attention in recent years. In this work, composite separators were fabricated by applying a ceramic-based composite coating composed of a metal hydroxide as a filler and flame-retardant agent (Aluminium hydroxide, Al(OH)3) and a binder (Poly(vinylidene Fluoride-co-hexafluoropropylene), P(VDF-HFP)) to the polypropylene (PP) commercial separator. Thermal shrinkage, thickness, air permeability, porosity, wettability, ionic conductivity, flame retardancy, and electrochemical performance of the fabricated ceramic-coated composite separator were investigated. The results showed that the addition of Al(OH)3 particles improved thermal shrinkage ( 8 %) and flame retardancy of the commercial separator, which can prevent dimensional changes at high temperatures and significantly increase LIBs safety. Applied 11 µm ceramic-based coating layer on PP commercial separator had 76 % porosity that increased the value of air permeability from 278.15 (s/100 cc air) to 312.8 (s/100 cc air), causing much facile air permeation through the pores of commercial separator than the composite one. Furthermore, suitable electrolyte uptake and the contact angle of ceramic coated separator (135 % and 91.19°, respectively) facilitated ion transport through the pores, which effectively improved the ionic conductivity of Al(OH)3-coated PP separator (about 1.4 times higher than bare separator). Moreover, the cell comprising Al(OH)3-coated PP separator had better cyclic performance than that of bare PP separator. All these characteristics make the fabricated flame-retardant Al(OH)3 composite separator an appropriate candidate to ensure the safety of the large-scale LIB.