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1.
Heliyon ; 10(3): e25064, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38352738

RESUMEN

Breast cancer remains a significant global health concern, necessitating the development of novel therapeutic approaches. In this study, we investigate the role of Eu3+ doped hydroxyapatite nanocomposites (Han: Eu3+) in the treatment of MCF7 and 4T1 breast cancer cell lines. Furthermore, we explored the structural and luminescent properties of these nanocomposites. Han: Eu3+ were synthesized using a modified co-precipitation method, and their morphology and crystal structure were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD) in which the average crystalline size of Han: Eu3+ was found to be 25 nm, rendering them suitable for cellular uptake and targeted therapy. To gain insights into the luminescent properties of Han: Eu3+, their excitation and emission spectra were recorded using photoluminescence spectrometer. The characteristic red emission of Eu3+ ions was observed upon excitation, validating the successful doping of Eu3+ into the Han lattice, which was confirmed by the CIE chromaticity coordinate study. These luminescent properties of Han: Eu3+ hold promise for potential applications in bioimaging. To evaluate the efficacy of Han: Eu3+ in breast cancer treatment, MCF7 and 4T1 cell lines were exposed to varying concentrations of the nanocomposites. Cell viability assays revealed a concentration-dependent reduction in cell viability, indicating the potential anticancer activity of Han: Eu3+. The findings of this study contribute to the expanding field of nanomedicine, bringing targeted breast cancer treatments and us closer to more effective.

2.
Cell Biochem Biophys ; 82(1): 247-257, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38183602

RESUMEN

The present study aimed to investigate the purified protein from the epidermal mucus of marine catfish Tachysurus dussumieri on the human colon cancer cell line. The bioactive protein was purified with the Anion exchange chromatography and the collected fractions were then tested to assess cell viability in HT 29 cells through the MTT assay. The most responding active purified protein fraction (PPF III) was characterized with the MALDI-TOF/MS it shared a similar homology and sequence with 90% of antimicrobial peptides from external secretions of amphibians. Typical morphological changes of apoptotic cells, including cell shrinkage and detachment, DNA damage, and nuclear condensation were observed after the treatment of bioactive protein. PPF III triggered ROS, increasing the LDH activity, disruption of mitochondrial membrane potential, and upregulation of Cleaved caspase 3/9, Cytochrome-c, Bax, and downregulation of Bcl-2 protein and gene expression on HT 29 cells.


Asunto(s)
Bagres , Neoplasias del Colon , Animales , Humanos , Apoptosis , Bagres/metabolismo , Extractos Vegetales/farmacología , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Células HT29 , Caspasa 3/metabolismo , Línea Celular Tumoral , Proliferación Celular , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial
3.
Heliyon ; 9(10): e20824, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37867874

RESUMEN

Photocatalysts workable under direct sunlight are the safe and cost-effective option for water purification. The nanocomposites of strontium oxide and zinc oxide (SZ NCs) were synthesized using coprecipitation method. The respective precursors of SZ NCs were subjected to alkaline hydrolysis and subsequently thermally treated to yield SZ NCs. The SZ NCs with different ZnO composition was synthesized by varying the concentration of ZnO precursor from 0.2 to 1 M. The structural properties of SZ NCs evaluated using X-Ray diffraction (XRD), Thermogravimetric analysis (TGA), and Differential thermal analysis DTA). The optical properties of SZ NCs studied using ultraviolet-visible (UV-Vis) spectroscopic study. The trend observed in the intensity of XRD peaks indicated the occurrence of Zn doping in the crystalline lattice of SrO and the formation of SrO-ZnO composite. Upon incorporation of 1 M of ZnO precursor, the grain size of the SrO was decreased from 49.3 to 27.6 nm. The weight loss in the thermal analysis indicates the removal of carbonates from the sample upon heating and shows the formation of an oxide structure. UV-Vis spectra confirmed that the presence of SrO enhanced the sunlight absorption of SZ NCs. The increase in the composition of ZnO precursors increased the bandgap of SrO (2.09 eV) to the level of ZnO (3.14 eV). SZ NCs exhibited heterostructure morphology, where the nanosized domains with varying shapes (layered and rod-like) were observed. Under direct sunlight conditions, SZ NCs prepared using 1 M/0.6 M of SrO/ZnO precursors exhibited 15-20 % higher photocatalytic efficiency than neat SrO and ZnO. In precise, 1 mg of this SZ NC was degraded 98 % of malachite green dye dissolved in water (10 ppm) under direct sunlight. Additionally, the thermal stability results showed that 18 % decomposition was obtained due to the degradation impurities in SrO/ZnO catalysts and the XRD results revealed that no structural change is obtained in SrO/ZnO photocatalysts after stability test. The SZ NCs can be effectively used as safe and economic sunlight photocatalysts for water purification in remote areas without the electricity.

4.
Emerg Microbes Infect ; 12(2): 2222850, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37279167

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been detected in wastewater. Wastewater-based epidemiology (WBE) is a practical and cost-effective tool for the assessment and controlling of pandemics and probably for examining SARS-CoV-2 presence. Implementation of WBE during the outbreaks is not without limitations. Temperature, suspended solids, pH, and disinfectants affect the stability of viruses in wastewater. Due to these limitations, instruments and techniques have been utilized to detect SARS-CoV-2. SARS-CoV-2 has been detected in sewage using various concentration methods and computer-aided analyzes. RT-qPCR, ddRT-PCR, multiplex PCR, RT-LAMP, and electrochemical immunosensors have been employed to detect low levels of viral contamination. Inactivation of SARS-CoV-2 is a crucial preventive measure against coronavirus disease 2019 (COVID-19). To better assess the role of wastewater as a transmission route, detection, and quantification methods need to be refined. In this paper, the latest improvements in quantification, detection, and inactivation of SARS-CoV-2 in wastewater are explained. Finally, limitations and future research recommendations are thoroughly described.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Aguas Residuales , Agua , Inmunoensayo
5.
J Environ Manage ; 317: 115367, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35636111

RESUMEN

Two-dimensional (2D) lamellar graphene oxide (GO) membranes are emerging as attractive materials for molecular separation in water treatment because of their single atomic thickness, excellent hydrophilicity, large specific surface areas, and controllable properties. To yet, commercialization of GO laminar membranes has been hindered by their propensity to swell in hydrated conditions. Thus, chemical crosslinking of GO sheets with the polymer matrix is used to improve GO membrane hydration stability. This review focuses on pertinent themes such as how chemical crosslinking improves the hydration stability, separation performance, and antifouling properties of GO membranes.


Asunto(s)
Grafito , Purificación del Agua , Grafito/química , Membranas Artificiales , Polímeros/química , Purificación del Agua/métodos
6.
Anal Chim Acta ; 1203: 339698, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35361436

RESUMEN

In this work, Fe/Ni bimetallic nitrogen-doped porous graphene (Fe/Ni-NPG) nanomaterials with rich pores, strong magnetism and good reusability were successfully prepared by one-step combustion and can be used as magnetic solid phase extraction (MSPE) adsorbents for the determination of 5-nitroimidazoles (5-NDZs) in environmental water samples. The dispersion and active sites of the materials were increased by the introduction of nitrogen. The adsorption behavior of Fe/Ni-NPG for 5-NDZs was investigated, which corresponds to the quasi-second-order kinetics and Langmuir adsorption model. The π-π electron donor-acceptor interaction (π-π EDA), hydrogen bond and electrostatic interaction between Fe/Ni-NPG and 5-NDZs are the main factors that help to obtain excellent adsorption properties. Several important conditions of MSPE are systematically optimized. Under the optimal MSPE conditions, the linear range of DMZ was 0.6-500 µg/L, the linear range of TNZ and ONZ was 0.7-500 µg/L, and the correlation coefficient R2 ≥ 0.9991. The limit of detection was 0.18-0.2 µg/L, the limit of quantification was 0.6-0.7 µg/L, and the RSDs of intraday and interday precision were 1.58%-4.66% and 3.77-9.69%, respectively. In the three spiked actual environmental water samples, the recovery was 78.05%-107.05% (RSDs<7.82%). The results show that this method based on Fe/Ni-NPG provides an accurate and reliable way to detect 5-NDZs in environmental water.


Asunto(s)
Grafito , Nitroimidazoles , Contaminantes Químicos del Agua , Fenómenos Magnéticos , Nitrógeno , Porosidad , Extracción en Fase Sólida/métodos , Agua , Contaminantes Químicos del Agua/análisis
7.
Chemosphere ; 286(Pt 2): 131799, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34364235

RESUMEN

Hydroxyapatite-decorated activated carbon (HAp/AC) nanocomposite was synthesized and utilized as a nanofiller to fabricate a novel type of polyethersulfone (PES) nanocomposite ultrafiltration (UF) membranes. Activated carbon (AC) derived from orange peel was synthesized by low-temperature pyrolysis at 400 °C. A hydroxyapatite/AC (HAp/AC) nanocomposite was developed by a simple one-pot hydrothermal synthesis method. The UF membrane was fabricated by intercalating HAp/AC fillers into PES casting solution by the non-solvent induced phase separation (NIPS) process. The prepared membranes exhibited a lower water contact angle than the pristine PES membrane. The hybrid membrane with 4 wt% HAp/AC nanocomposite displayed 4.6 times higher pure water flux (~660 L/m2 h) than that of the pristine membrane (143 L/m2 h). In static adsorption experiments, it was found that the amount of humic acid (HA) and bovine serum albumin (BSA) adsorbed by the HAp/AC-PES hybrid membrane was much lower than that of the original membrane due to the electrostatic repulsive forces between them and the surface of the membrane. Irreversible fouling was reduced from 33 to 6 % for HA and from 46 to 8 % for BSA after HAp/AC was incorporated into the PES matrix. After 7 cycles of water-BSA-water, the HAp/AC-PES hybrid membrane maintained a high pure water flux of 540 L/m2 h with an excellent flux recovery ratio (FRR), demonstrating the long-term stability of the membranes. The developed UF membranes outperformed the original PES membranes in terms of permeability, selectivity, and antifouling.


Asunto(s)
Nanocompuestos , Ultrafiltración , Carbón Orgánico , Durapatita , Membranas Artificiales , Permeabilidad , Agua
8.
Chemosphere ; 289: 133144, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34863730

RESUMEN

An enhanced water flux and anti-fouling nanocomposite ultrafiltration membrane based on quaternary ammoniumpropylated polysilsesquioxane (QAPS)/cellulose acetate (QAPS@CA) was fabricated by in situ sol-gel processing via phase inversion followed by quaternization with methyl iodide (CH3I). Membrane characterizations were performed based on the contact angle, FTIR, SEM, and TGA properties. Membrane separation performance was assessed in terms of pure water flux, rejection, and fouling resistance. The 7%QAPS@CA nanocomposite membrane showed an increased wettability (46.6° water contact angle), water uptake (113%) and a high pure water permeability of ∼370 L m-2 h-1 bar-1. Furthermore, the 7%QAPS@CA nanocomposite membrane exhibited excellent bactericidal properties (∼97.5% growth inhibition) against Escherichia coli (E. coli) compared to the bare CA membrane (0% growth inhibition). The 7%QAPS@CA nanocomposite membrane can be recommended for water treatment and biomedical applications.


Asunto(s)
Escherichia coli , Membranas Artificiales , Celulosa/análogos & derivados , Interacciones Hidrofóbicas e Hidrofílicas , Compuestos de Organosilicio
9.
Chemosphere ; 268: 129306, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33360002

RESUMEN

To extend the use of polyethersulfone (PES) ultrafiltration membranes in water process engineering, the membrane's wettability and anti-fouling properties should be further improved. In this context, hydroxyapatite/boron nitride (HAp/BN) nanocomposites have been prepared and intercalated into PES membranes using a non-solvent-induced phase separation process. High-quality 2D transparent boron nitride nanosheets (BN NSs) were prepared using an environmentally friendly and green-template assisted synthesis method in which 1D hexagonal hydroxyapatite nanosheets (HAp NRs) were uniformly distributed and hydrothermally immobilized at 180 °C. SEM, XRD, and Raman spectroscopy techniques were used to characterize the HAp/BN nanocomposites. PES membranes intercalated with various nanocomposite amounts (0-4 wt %) were also characterized by permeability, porosity, and contact angle measurements. Additional pathways for water molecule transport were promoted by the high surface area of the BN NSs, resulting in high permeability. Membrane wettability and antifouling properties were also improved by the inclusion of negative charge groups (OH- and PO43-) on HAp. Hybrid membranes containing 4 wt% HAp/BN showed the best overall performance with ∼97% increase in water flux, 90% rejection of bovine serum albumin (BSA), high water flux recovery ratio, low irreversible fouling, and high reversible fouling pattern. The intercalation of HAp/BN with the PES matrix therefore opens up a new direction to enhance the PES UF membranes' hydrophilicity, water flux, and antifouling capacity.


Asunto(s)
Nanocompuestos , Ultrafiltración , Compuestos de Boro , Durapatita , Membranas Artificiales , Permeabilidad , Polímeros , Sulfonas
10.
Chemosphere ; 261: 127687, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32750620

RESUMEN

One of the major challenges facing the practical application of forward osmosis (FO) membranes is the need for high performance. Thus, the fabrication of highly permselective FO membranes is of great importance. The objective of this study was to improve the wettability/hydrophilicity of electrospun nanofiber (ESNF)-based substrates for the fabrication of nanofiber-supported thin film composite (NTFC) membranes for FO application. This study explored the impact of electrospun polyethersulfone/polyacrylonitrile (PES/PAN) nanofibers as the blend support to produce NTFC membranes. The blending of PES/PAN in the spinning dope was optimized. The blending of hydrophilic PAN (0-10 wt%) in PES affects the fiber diameter, hydrophilicity, water uptake, and roughness of the ESNF membrane substrates. Continuous thermal-rolling pretreatment was performed on the ESNF substrates prior to interfacial polymerization for polyamide active layer deposition. The results indicated that the fabricated NTFC membrane achieved significantly greater water flux (L/m2 h) while retaining a low specific salt flux (g/L) compared to traditional TFC membranes. The NTFC membrane flux increased with an increase in PAN content in the ESNF substrate. According to the FO performance results, the NTFC-10 (PES/PAN blend ratio of 90:10) exhibited optimal performance: a high water flux of 42.1 and 52.2 L/m2 h for the FO and PRO modes, respectively, and low specific salt flux of 0.27 and 0.24 g/L for the FO and PRO modes, respectively, using 1 M NaCl as the draw solution. This demonstrated the higher selectivity and water flux achieved by the developed NTFC membranes compared to the traditional TFC membranes.


Asunto(s)
Nanofibras/química , Polímeros/química , Sulfonas/química , Resinas Acrílicas , Interacciones Hidrofóbicas e Hidrofílicas , Estudios Longitudinales , Membranas Artificiales , Nylons , Ósmosis , Cloruro de Sodio , Agua , Purificación del Agua/métodos
11.
Chemosphere ; 221: 479-485, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30654262

RESUMEN

Janus electrospun nanofiber membranes (J-ENMs) have attracted considerable interest as membranes for oil-in-water emulsion separation due to the opposite properties on each side of the membrane. Such properties can provide capillary effect and achieve water unidirectional transportation. However, the capillary effect on performances of the J-ENMs is still obscure. Therefore, it is highly important to investigate the relation of pore size, capillary pressure, and fluid flux of them. For this study, J-ENMs, which have a dual-layer structure with hydrophilic polyacrylonitrile (PAN) and hydrophobic polystyrene (PS) nanofibrous membranes simultaneously, were fabricated via the electrospinning process. Among the fabricated membranes, the large pore sizes of the PS layer of J-ENMs affected capillary pressure leading to a pure water flux increase of nine times that of the small pore size. For emulsion flux, oil droplets can pass through a large pore of the PS layer easily and can cause a decrease in emulsion flux. Nevertheless, the emulsion flux of J-ENMs was 1.7 times higher than that of single layer membrane, which showed a promising application for the oil/water separation field.


Asunto(s)
Emulsiones/química , Membranas Artificiales , Nanofibras , Purificación del Agua/métodos , Nanofibras/química , Aceites , Porosidad , Agua
12.
Membranes (Basel) ; 8(3)2018 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-30189665

RESUMEN

This experimental study explores the potential of supported ionic liquid membranes (SILMs) based on protic imidazolium ionic liquids (ILs) and randomly nanoporous polybenzimidazole (PBI) supports for CH4/N2 separation. In particular, three classes of SILMs have been prepared by the infiltration of porous PBI membranes with different protic moieties: 1-H-3-methylimidazolium bis (trifluoromethane sulfonyl)imide; 1-H-3-vinylimidazolium bis(trifluoromethane sulfonyl)imide followed by in situ ultraviolet (UV) polymerization to poly[1-(3H-imidazolium)ethylene] bis(trifluoromethanesulfonyl)imide. The polymerization process has been monitored by Fourier transform infrared (FTIR) spectroscopy and the concentration of the protic entities in the SILMs has been evaluated by thermogravimetric analysis (TGA). Single gas permeability values of N2 and CH4 at 313 K, 333 K and 363 K were obtained from a series of experiments conducted in a batch gas permeance system. The results obtained were assessed in terms of the preferential cavity formation and favorable solvation of methane in the apolar domains of the protic ionic network. The most attractive behavior exhibited poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide polymeric ionic liquid (PIL) cross-linked with 1% divinylbenzene supported membranes, showing stable performance when increasing the upstream pressure. The CH4/N2 permselectivity value of 2.1 with CH4 permeability of 156 Barrer at 363 K suggests that the transport mechanism of the as-prepared SILMs is solubility-dominated.

13.
ACS Appl Mater Interfaces ; 9(17): 14844-14857, 2017 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-28437079

RESUMEN

Liquid-induced phase-separation micromolding (LIPSµM) has been successfully used for manufacturing hierarchical porous polybenzimidazole (HPBI) microsieves (42-46% porosity, 30-40 µm thick) with a specific pore architecture (pattern of macropores: ∼9 µm in size, perforated, dispersed in a porous matrix with a 50-100 nm pore size). Using these microsieves, proton-exchange membranes were fabricated by the infiltration of a 1H-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide liquid and divinylbenzene (as a cross-linker), followed by in situ UV polymerization. Our approach relies on the separation of the ion conducting function from the structural support function. Thus, the polymeric ionic liquid (PIL) moiety plays the role of a proton conductor, whereas the HPBI microsieve ensures the mechanical resistance of the system. The influence of the porous support architecture on both proton transport performance and mechanical strength has been specifically investigated by means of comparison with straight macroporous (36% porosity) and randomly nanoporous (68% porosity) PBI counterparts. The most attractive results were obtained with the poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide PIL cross-linked with 1% divinylbenzene supported on HPBI membranes with a 21-µm-thick skin layer, achieving conductivity values up to 85 mS cm-1 at 200 °C under anhydrous conditions and in the absence of mineral acids.

14.
ACS Appl Mater Interfaces ; 8(51): 35377-35389, 2016 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-27976844

RESUMEN

Polymeric ionic liquids (PILs) have triggered great interest as all solid-state flexible electrolytes because of safety and superior thermal, chemical, and electrochemical stability. It is of great importance to fabricate highly conductive electrolyte membranes capable to operate above 120 °C under anhydrous conditions and in the absence of mineral acids, without sacrificing the mechanical behavior. Herein, the diminished dimensional and mechanical stability of poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide has been improved thanks to its infiltration on a polybenzimidale (PBI) support with specific pore architecture. Our innovative solution is based on the synergic combination of an emerging class of materials and sustainable large-scale manufacturing techniques (UV polymerization and replication by microtransfer-molding). Following this approach, the PIL plays the proton conduction role, and the PBI microsieve (SPBI) mainly provides the mechanical reinforcement. Among the resulting electrolyte membranes, conductivity values above 50 mS·cm-1 at 200 °C and 10.0 MPa as tensile stress are shown by straight microchannels of poly[1-(3H-imidazolium)ethylene]bis(trifluoromethanesulfonyl)imide cross-linked with 1% of dyvinylbenzene embedded in a PBI microsieve with well-defined porosity (36%) and pore diameter (17 µm).

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