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1.
Int J Biol Macromol ; 262(Pt 2): 129946, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340936

RESUMO

Organic dye pollution from textiles and other industries presents a substantial risk to people and aquatic life. The use of photocatalysis to decolorize water using the strength of UV light is one of the most important remediation techniques. In the present study, a novel nanocomposites hydrogel including carboxymethyl cellulose (CMC), acrylic acid (AAc), Zinc oxide (ZnO), and silver (Ag) nanoparticles was produced using an eco-friendly γ-irradiation technique for photocatalytic decolorization applications. ZnO and Ag nanoparticles were distributed in the CMC/AAc hydrogel matrix without significant aggregation. SEM, XRD, EDX, TEM, and FTIR analyses were used to assess the physicochemical characteristics of the nanocomposite samples. Carboxymethyl cellulose/acrylic acid/Zinc oxide doped silver (CMC/PAAc/ZnO@Ag) nanocomposite hydrogels were developed and utilized in the photocatalytic decolorization of the lerui acid brilliant blue dye (LABB) when exposed to ultraviolet (UV) radiation. UV- Vis spectrophotometry was utilized to analyze the optical properties of the produced nanostructure. Regarding the decolorization of the LABB, the impacts of operational variables were investigated. The optimum conditions for decolorization (93 %) were an initial concentration of 50 mg/L, pH = 4, catalyst dosage of 50 g/L, and exposure time of 90 min. The results illustrated that the LABB acidic dye from wastewater was remarkably decolored.


Assuntos
Acrilatos , Benzenossulfonatos , Nanopartículas Metálicas , Nanocompostos , Óxido de Zinco , Humanos , Óxido de Zinco/química , Hidrogéis/química , Prata/química , Carboximetilcelulose Sódica/química , Nanopartículas Metálicas/química , Corantes/química , Nanocompostos/química
2.
Int J Biol Macromol ; 243: 125121, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37263325

RESUMO

Organic dye contamination, emanating from pharmaceutical, paper, and textile industries into water resources, severely threatens marine and human life even at low concentrations. Photocatalysis is one of the most important remediation techniques that decolorize water by employing the power of light. In this work, the development of floated beads of Sodium Alginate/hydroxyethyl methacrylate (Alg-g-HEMA) encompass graphene oxide (GO) decorated Zinc oxide (ZnO) utilizing ionizing radiation was designed to function as a photocatalyst when exposed to visible light. Floatability was induced using calcium carbonate. GO was sonochemically decorated with ZnO nanoparticles and the yield was characterized using XRD, FTIR, TEM, SEM, and EDX techniques. Optical characteristics of the developed nanostructure were performed using UV-Vis spectrophotometry. The photocatalytic activity of the floated (Alg-g-HEMA)-ZnO@GO beads was assessed for the photo decolorization of methylene blue dye (MB) under visible light. The upshot of operational factors such as photocatalyst dose, pH, initial dye concentration, and irradiation time on the decolorization of MB was examined. It was observed that 1 g of the developed (Alg-g-HEMA)-ZnO@GO photocatalyst was able to decolorize 1000 ml of 20 ppm of MB within 150 min at pH 9. In terms of kinetics, photo-decolorization follows Langmuir Hinshelwood pseudo-first order.


Assuntos
Óxido de Zinco , Humanos , Óxido de Zinco/química , Azul de Metileno/química , Luz
3.
Environ Technol ; 43(3): 311-326, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32571180

RESUMO

ABSTRACTThe present work focuses on the synthesis of a proton exchange membrane to be assembled in a microbial fuel cell (MFC) for simultaneous bioelectricity production and domestic wastewater treatment. The indigenous membrane was prepared by ionizing irradiation-induced graft copolymerization of glycidyl methacrylate (GMA) and vinyl acetate (VAc) onto low-density polyethylene and subsequently, the prepared grafted sheets were sulfonated via epoxy ring-opening of PGMA moieties. Parameters affecting the grafting degree were investigated and the prepared membranes were characterized by investigating their structural, thermal, mechanical, and electrical properties. Some physicochemical characteristics including ion exchange capacity, sulfonation density, and proton conductivity were also evaluated. The data confirmed the success of the preparation protocol to obtain a suitable membrane for the proposed application. Moreover, the performance of the assembled MFC was thoroughly investigated through the evaluation of its electrochemical behaviour including cyclic voltammetry, electrochemical impedance spectroscopy, columbic efficiency, and wastewater treatment capability. The sulfonated LDPE-g-P(GMA-co-VAc) membrane of 80% grafting degree shows substantial removal of chemical oxygen demand up to about 90% with columbic efficiency of 10.1%, columbic recovery of 8.7%, rate of energy harvest of 2.1 C/h and power density of 2.72 W m-2. However, the use of 10 mM of KMnO4 as electron acceptor drastically increase the harvested power density to reach 356.4 W m-2.


Assuntos
Fontes de Energia Bioelétrica , Compostos de Epóxi , Metacrilatos , Polietileno , Prótons , Compostos de Vinila
4.
Drug Deliv Transl Res ; 8(1): 191-203, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29280061

RESUMO

In an effort to increase the oral bioavailability of Amphotericin B (AmB), a pH-sensitive drug carrier composed of Tragacanth (Trag) and acrylic acid (AAc) was prepared using γ-irradiation. The swelling behavior of (Trag/AAc) hydrogels was characterized as a function of pH and ionic strength of the swelling medium. The obtained swelling indices revealed the ability of the prepared hydrogel to protect a loaded drug in stomach-simulated medium (Fickian behavior) and to release such drug in intestinal-simulated medium (non-Fickian behavior). In vitro release studies of the antifungal (AmB) were performed to evaluate the hydrogel potential as a drug carrier. The antifungal activity of the prepared oral formulation was investigated in a mouse model of systemic candidiasis. Data revealed that (Trag/AAc)-AmB has a potent antifungal efficacy as demonstrated by prolonging the survival time and reducing the tissue fungal burden, serum antibody titers, as well as inflammatory cytokines in kidney and liver tissues. Furthermore, in vivo toxicity of (Trag/AAc)-AmB was assessed via measuring kidney and liver functions, and results displayed the safety of this novel AmB formulation which was confirmed by histopathological examination. Overall, results indicated that the prepared (Trag/AAc)-AmB is an effective oral delivery system for AmB with better bioavailability and minimal toxicity and could represent a promising approach for improving the therapeutic index of the drug.


Assuntos
Acrilatos/administração & dosagem , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Candidíase/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Hidrogéis/administração & dosagem , Tragacanto/administração & dosagem , Acrilatos/química , Acrilatos/toxicidade , Administração Oral , Anfotericina B/química , Anfotericina B/toxicidade , Animais , Anticorpos Antifúngicos/sangue , Antifúngicos/química , Antifúngicos/toxicidade , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candida albicans/imunologia , Candidíase/sangue , Candidíase/imunologia , Candidíase/microbiologia , Citocinas/imunologia , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Hidrogéis/química , Hidrogéis/toxicidade , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Rim/efeitos dos fármacos , Rim/imunologia , Rim/microbiologia , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/microbiologia , Fígado/patologia , Masculino , Camundongos , Tragacanto/química , Tragacanto/toxicidade
5.
J Biomed Mater Res B Appl Biomater ; 81(1): 168-74, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16924606

RESUMO

pH-sensitive hydrogels were prepared from poly(ethylene glycol) (PEG) and acrylic acid (AAc) in aqueous solution employing gamma-radiation-induced copolymerization and crosslinking. The swelling behavior of the prepared hydrogels was determined by investigating the time and pH-dependent swelling of the (PEG/AAc) hydrogels of different PEG content. The effect of environmental parameters such as pH and ionic strength on the swelling kinetics was studied. The results not only show the dependence of the swelling indices on the pH value of the swelling medium but also show a clear dependence of the diffusion coefficient on the ionic strength of the medium. To estimate the ability of the prepared copolymer to be used as a colon-specific drug carrier, the release of ketoprofen was studied as a function of time at pH 1 and pH 7.


Assuntos
Acrilatos/química , Portadores de Fármacos/química , Hidrogéis/síntese química , Polietilenoglicóis/química , Anti-Inflamatórios não Esteroides/química , Portadores de Fármacos/síntese química , Raios gama , Concentração de Íons de Hidrogênio , Cetoprofeno/química , Concentração Osmolar
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