RESUMO
In the 1970s, sperm cryopreservation was presented as a unique route to fertility preservation. The ability to cryopreserve sperm from all species is challenging. The sperm cryopreservation process encompasses various cellular stresses such as increased osmotic pressure, ice crystal formation, and thermal shock, therefore decreasing the quality of sperm. The nanostructures due to their inherent features such as reactivity, high uptake, active surface area, and antioxidant activity, have contributed to modifying freezing protocols. In this review, the current state of the art with regards to emerging applications of nanotechnology in sperm cryopreservation are reviewed, some of the most promising advances are summarized, and the limitations and advantages are comprehensively discussed.
Assuntos
Criopreservação , Crioprotetores , Nanoestruturas , Preservação do Sêmen , Espermatozoides , Criopreservação/métodos , Masculino , Nanoestruturas/química , Humanos , Espermatozoides/efeitos dos fármacos , Preservação do Sêmen/métodos , Crioprotetores/farmacologia , Crioprotetores/química , Animais , Nanotecnologia/métodos , Preservação da Fertilidade/métodosRESUMO
INTRODUCTION: The aim of this study was to understand the trends of teaching Computer Aided Design/Computer Aided Manufacturing (CAD/CAM) in the undergraduate dental curriculum in the MENA region by conducting an online survey among the undergraduate dental colleges in this region. MATERIALS AND METHODS: An online survey was conducted using Google Forms consisting of 20 questions that could be answered by "yes" or "no" responses, multiple-choice answers or in a descriptive, "open" format. A total of 55 participants from the MENA region representing their dental college were requested to participate in this study. RESULTS: The response rate of the survey was 85.5% following the twofold follow-up reminders method. Although the vast majority of professors demonstrated vital knowledge in the practical use of CAD/CAM, the majority of them did not provide theoretical and practical training on CAD/CAM in their institutions. Among the schools with established levels of teaching CAD/CAM, nearly 50% of them provide both pre-clinical and clinical training on CAD/CAM. Despite the availability of extra-curricular training courses on CAD/CAM outside the university setting, there is a lack of advocating for students to enrol in those courses by the institutions. More than 80% of the participants agreed that CAD/CAM has a strong future in chair-side dental clinics and CAD/CAM needs to be incorporated within undergraduate studies. CONCLUSION: Based on the results of the current study, it is understandable that an intervention is required by the dental education providers to cope with the growing demand for CAD/CAM technology for the current and future dental practitioners of the MENA region.
Assuntos
Odontólogos , Educação em Odontologia , Humanos , Papel Profissional , Estudantes , Tecnologia , Desenho Assistido por ComputadorRESUMO
BACKGROUND: Health impact assessments (HIA) of policies and projects are conducted differently in different contexts although there has been less HIA research to date in non-western countries. Global HIA research has however suggested that the technical conduct of HIAs is tied to broader conditions and influences to do with decision making and policy development. This study was conducted to develop a conceptual framework for progressing HIA in Iran including all factors influencing HIA planning and practice. METHODS: A comprehensive review of the international HIA literature identified core characteristics and principles. Then key informant interviews (n = 14) identified Iranian perspectives about factors influencing HIAs practice. These two stages resulted in a conceptual framework for HIA planning and practice including influencing factors and HIA content that was confirmed by our participants using e-Delphi technique. RESULTS: 91 HIA characteristics were organized into 20 categories. The interviews showed that four core concepts i.e. context, actors, HIA principles and policies and HIA capacities influence HIA practice in Iran. Comprehensive content of HIA considering all health dimensions and health determinants, assessing health inequalities, appropriate HIA type, quantification and participation is formed under influence of the above mentioned four factors. The study also demonstrated need to redefine the HIA principles and make decision about integration of HIA in Environmental Impact Assessment and also about the level of HIA before implementing HIA. The e-Delphi resulted in expert consensus on the variables, concepts, and their relations in proposed framework. CONCLUSIONS: Progressing HIA practice in Iran is perceived locally as subject to similar contextual conditions to those identified in the international literature. Further we have demonstrated the utility of mixed methods to progress HIA implementation in differing country contexts.
Assuntos
Avaliação do Impacto na Saúde/estatística & dados numéricos , Promoção da Saúde/organização & administração , Formulação de Políticas , Tomada de Decisões Gerenciais , Humanos , Irã (Geográfico) , Programas Nacionais de Saúde/organização & administração , Grupos Populacionais/estatística & dados numéricosRESUMO
The present study was undertaken to develop an effective adsorbent and to study the adsorption of Ethidium bromide and Ethidium monoazide bromide from aqueous solution using the CuO nanoparticles. The characteristics of CuO nanoparticles were determined and found to have a surface area 89.59m(2)/g. Operational parameters such as pH, contact time and adsorbent concentration, initial concentration and temperature were also studied. The amount of removal increases with the increase in pH from one to seven and reaches the maximum when the pH is nine. Adsorption data fitted well with the Langmuir, Freundlich and Florry-Huggins models. The results show that the best fit was achieved with the Langmuir isotherm equation with maximum adsorption capacities of 0.868 and 0.662mg/g for Ethidium bromide and Ethidium monoazide bromide, respectively. The adsorption process was found to follow pseudo-second-order kinetics. The calculated thermodynamic parameters, namely ΔG, ΔH and ΔS showed that adsorption of Ethidium bromide and Ethidium monoazide bromide was spontaneous and endothermic under examined conditions.
Assuntos
Azidas/química , Cobre/química , Etídio/química , Nanopartículas/química , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Temperatura , Poluentes Químicos da Água/químicaRESUMO
Samples of surface sediments from the Iranian coast of the Persian Gulf were examined to determine the levels and sources of 15 polycyclic aromatic hydrocarbons (PAHs). Samples were collected from 30 sampling sites and analyzed for PAHs by gas chromatography-mass spectrometry (GC-MS). Total concentrations of PAHs ranged from 93 to 4,077 ng g(-1) dry weight. The PAH composition from 30 sampling sites was dominated by four-ring PAH compounds. Molecular indices based on the ratios of PAH concentrations were used to differentiate PAHs from pyrolitic to petrogenic and mixed origins. The results suggested that the main sources of PAHs in sediments from the studied region were mixed pyrolitic and petrogenic. Furthermore, benthic organisms in most of the investigated areas were not at ecotoxicological risk, according to the results from the effects range low (ERL)/effects range median (ERM) techniques suggested by the US Sediment Quality Guidelines (SQGs).
Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Ecotoxicologia , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Oceano Índico , Irã (Geográfico)RESUMO
Fanconi anemia (FA) is a genetic disorder that occurs when certain genes responsible for repairing DNA replication and promoting homologous recombination fail to function properly. This leads to severe clinical symptoms and a wide range of cancer-related characteristics. Recent treatment approaches for FA involve hematopoietic stem cell transplantation (HSCT), which helps restore the population of stem cells. A survival study using p-values indicated that specific hub genes play a significant role in diagnosing and predicting the disease. To find potential medications that interact with the identified hub genes, researchers inferred drugs. Among hub genes, TP53 was found to be particularly promising through computational analysis. Further investigation focused on two drugs, Topiramate and Tocofersolan predicted based on drug bank database analysis. Molecular docking strategies were employed to assess the best binding pose of these drugs with TP53. Topiramate showed a binding affinity of -6.5 kcal/mol, while Tocofersolan showed -8.5 kcal/mol against the active residues within the binding pocket. Molecular dynamics (MD) simulations were conducted to observe the stability of each drug's interaction with the TP53 protein over time. Both drugs exhibited stable confirmation with only slight changes in the loop region of the TP53 protein during the simulation intervals. Results also shows that there was a high fluctuation observed during apo-sate simulation time intervals as compared to complex system. Hence, it is suggested that the exploration of structure-based drug design holds promising results to specific target. This could potentially lead to a breakthrough in future experimental approaches for FA treatment.Communicated by Ramaswamy H. Sarma.
RESUMO
In this study, the hydrothermal method was used to synthesis of silver indium sulfide/nickel molybdenum sulfide (AgInS2/NiMoS4) nanostructure and decorated on Palygorskite (Plg) as an excellent carrier of antibacterial materials. The performance of the prepared AgInS2/NiMoS4/Plg composites was investigated for light-driven antibacterial process and detection of uric acid from biological samples. The result shows the highest antibacterial activity of the AgInS2/NiMoS4/Plg with the minimum inhibitory concentrations about 0.2-0.3 mg/mL. The prepared AgInS2/NiMoS4/Plg as sensor depicted enhanced peroxidase-like activity for detection of acid uric. The detection limit of acid uric by AgInS2/NiMoS4/Plg was about 26.1 nM. Therefore, the AgInS2/NiMoS4/Plg can be developed in the bactericidal process and sensing in complex biological systems.
Assuntos
Gota , Nanoestruturas , Antibacterianos/farmacologia , Argila , Dissulfetos , Humanos , Índio/química , Minerais , Molibdênio , Nanoestruturas/química , Níquel , Prata/química , Ácido ÚricoRESUMO
In this study, the Cu2MoS4/WO3 supported on chitosan was prepared by precipitation method, and applied to photocatalyst, antibacterial agent and biosensor. The presence of WO3 and Cu2MoS4 crystals were confirmed by XRD analysis. The elemental information was investigated by EDS. FTIR spectra shows the presence of chitosan in nanocomposites. The as-synthesized Cu2MoS4/WO3/Chitosan nanocomposites has a bandgap of 2.18 eV and it is effective for visible light condition. The average particle size of the Cu2MoS4/WO3/Chitosan is 71 nm. The photocatalysis activity Cu2MoS4/WO3/Chitosan was higher than Cu2MoS4 or WO3.The Cu2MoS4/WO3/Chitosan nanocomposites shows the highest efficiency (100%) in photocatalysis degradation of dye under visible light irradiation in 80 min. The â¢O2- plays a main role in degradation process. The as-synthesized Cu2MoS4/WO3/Chitosan nanocomposites depicted the antibacterial activity toward G+/- bacteria. Determination of enterococcus faecalis is important for human health. The DNA template was used to the Cu2MoS4/WO3/Chitosan nanocomposites and applied in detection of enterococcus faecalis by H2O2 and 3,3',5,5' -tetramethylbenzidine in peroxidase like activity. The detection limit of enterococcus faecalis by DNA-Cu2MoS4/WO3/Chitosan in peroxidase-like catalysis was about 55 CFU/mL. Therefore, the Cu2MoS4/WO3/Chitosan can be applied in the photocatalysis, bactericidal and peroxidase process.
Assuntos
QuitosanaRESUMO
In this project, poly (citric acid) (PCA) functionalized on nano Ag/Cu was synthesized by chemical analysis method. The nano probe was applied to detection of cysteine by using the magnesium (II) ions as a cross linker. The characterization of Ag/Cu/PCA nano probe was studied by using the UV-visible, morphological microscopy, dynamic light scattering, and zeta potential analyzer. The zeta potential and size of Ag/Cu/PCA were -38.0 mV and 18.0 nm, respectively. The prepared nano probe shows rapid response for detection of cysteine. The detection limit of Ag/Cu/PCA nano probe was 0.07 nM. Additional, the Ag/Cu/PCA nanoparticles was applied to cysteine detection from real samples in the presence of amino acids compounds. Rapidly and sensitive determination of Streptococcus pneumoniae is substantial for food safety and human health. The DNA-Ag/Cu/PCA were prepared as a template in chemical method and experimented as a bio-receptor for the cell bacteria detection as peroxidase-like catalytic process. The DNA-Ag/Cu/PCA nano probe shows a linear dynamic concertation range of Streptococcus pneumoniae via detection limit about 65 CFU/mL. The project presents that the DNA-Ag/Cu/PCA could detect the biological and bacterial samples via high accuracy.
Assuntos
Colorimetria , Nanopartículas Metálicas , Aminoácidos , Bactérias , Cobre , Humanos , Peroxidases , PrataRESUMO
In this work, the fabrication of the CuO on ZnCdS as a heterojunction nanocomposites were conducted by hydrothermal method and the synthesis method was confirmed by the XRD, XPS, EDS, UV-vis spectrum analysis. The CuO/ZnCdS was used as a photocathode in the bio-photoelectrochemical system (BPES) for tetracycline (TC) degradation under solar irradiation. The CuO/ZnCdS photocathode indicated substantial photocatalytic efficiency for TC degradation, due to the fast separation and transfer of photogenerated carriers. The ESR test evaluates the mechanism of degradation, and shows that ·OH, and ·O2- were contributed to TC degradation. The TC degradation was 1.59 times higher than the unilluminated process (98.72% vs 61.71). The photocatalysis test shows that the TC was degraded about 90.5% in 1.5 h. Then, the synthesized CuO/ZnCdS nanocomposites were studied for the biological application such as antifungal activities. CuO/ZnCdS nanocomposites depicted substantial antimicrobial activity versus Candida-albicans by in vitro process. Therefore, this study suggests the novel system for the antibiotics degradation, and as antifungal application.
Assuntos
Microbiota , Nanocompostos , Óxido de Zinco , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Cádmio , Compostos de Cádmio , Catálise , Cobre/farmacologia , Óxidos , Sulfetos , Tetraciclina , Zinco , Compostos de ZincoRESUMO
The novel Ag0/Cu2MoO4 nanoparticles was simply synthesized via chemical method. Ag/Cu2MoO4 nanoparticles was characterized by FESEM image, XRD curve, UV-vis spectroscopy, BET analysis, and XPS spectrum. XRD pattern depicts that the cubic crystalline phase of particles. The band gap of Ag/Cu2MoO4 nanoparticles was achieved to 2.04 eV, which that depicted the best activity under visible light irradiation. Ag/Cu2MoO4 nanoparticles exhibits 99.74% degradation under light and persulfate ion which was higher response than Cu2MoO4 nanoparticles (83.56%) under this condition. The scavenging test indicates the important reactive species in removal process were â¢OH, and â¢SO4-. The Ag/Cu2MoO4 nanoparticles was indicated highly photo-stability for the MG degradation after 5th cycle. Ag/Cu2MoO4 exhibits substantial antibacterial properties against P. aeruginosa and S. pneumoniae. Moreover, Ag/Cu2MoO4 nanoparticles was experimented to peroxidase-like performance for the colorimetric detection of glucose with the Limit of Detection about 52.23 nM.
Assuntos
Glucose , Nanopartículas , Catálise , Antibacterianos/farmacologia , Antibacterianos/química , LuzRESUMO
Ag doped Sn3O4 Nanostructure and immobilized on hyperbranched polypyrrole is investigated in this project. The product was synthesized by the hydrothermal synthesis method. The surface and structural characteristics of the product was studied by different instrumental analysis. The fabricated nanocomposites was utilized as a nano photocatalyst in the removal of methylene blue dye. The crystallography results depicts the triclinic phase of Sn3O4 with the crystallite size 36.3 nm. The band gap of the Ag-Sn3O4/hyperbranched polypyrrole was found 1.50 eV from kubelka-munk measurements. The specific surface area was increased in the presence of the hyperbranched polypyrrole as compared to Ag-Sn3O4 samples. The photo-catalytic activity of composites was found 100.0% degradation of CR in 30 min under visible light irradiation. The catalytic kinetic was followed from the first kinetic model. Moreover, the Ag/Sn3O4/hyperbranched polypyrrole was applied as a bactericidal agent against Streptococcus pneumoniae, and Pseudomonas aeruginosa bacteria. Determination of Streptococcus pyogenes as a pathogenic bacteria was investigated by using aptamer/Ag/Sn3O4/hyperbranched polypyrrole in peroxidase activity. The detection limit of S. pyogenes was 71.0 CFU/mL by using the nano-aptamer.
Assuntos
Antibacterianos , Nanocompostos , Antibacterianos/química , Antibacterianos/farmacologia , Catálise , Luz , Nanocompostos/química , Polímeros , Pirróis , Prata/químicaRESUMO
Recently, photo-degradation process under ultraviolet-light irradiation is being used as a substantial treatment method for the removal of environmental pollution. In this study, a silver phosphate-ilmenite (Ag3PO4-FeTiO3) hetero structure supported on glycol chitosan catalyst was completely prepared, also, and its structural, and optical properties were characterized. Meantime, scanning electron microscopy, X-ray diffraction, X-ray photoelectron, and UV-vis spectra were applied. The Ag3PO4-FeTiO3/glycol chitosan catalyst was used to degrade metronidazole under visible-light irradiation. The degradation rate of metronidazole in 25 min by Ag3PO4-FeTiO3/glycol chitosan nanocomposites was found to be 99.2% under UV light irradiation, which was higher than that by Ag3PO4-FeTiO3 (72.24%) and FeTiO3 (35.5%), respectively. The active species trapping test of Ag3PO4-FeTiO3/glycol chitosan indicated that ·OH and ·O2- participated during the reaction. The diffusion method was evaluated to appraise the bactericidal activity of the synthesized nanomaterials when tested against both Staphylococcus aureus and Escherichia coli bacteria, with or without LED-light irradiation. The antibacterial tests show higher inhibition zones under light illumination as compared to dark conditions. The antifungal properties of the prepared nanomaterials were analyzed by fungi (Aspergillus niger, and Fusarium solani) using disc diffusion analysis. It was confirmed that the prepared nanomaterials have the best antifungal agent as compared to the standard antibiotics. When the Ag3PO4-FeTiO3/glycol chitosan was used, the amount of inhibition zone was enhanced.
Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Fosfatos/química , Compostos de Prata/química , Titânio/química , Antibacterianos/farmacologia , Catálise , Quitosana/química , Poluentes Ambientais/química , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Luz , Metronidazol/efeitos adversos , Metronidazol/química , Testes de Sensibilidade Microbiana , Nanocompostos/química , Staphylococcus aureus/efeitos dos fármacosRESUMO
In this project, bimetallic Au-Agnanoparticles/CuS nanoparticles were prepared via simple hydrothermal methods, which were used as highly efficient material for Cr (III) detection, photocatalytic, and biological process. The Au-Ag/CuS nanoparticles was studied via UV-visible spectroscopy, field-emission scanning electron microscopy, Dynamic light scattering, and X-ray diffraction. The zeta potential and effective size of Au-Ag/CuS nanoparticles was -32.1 mV and 25 nm respectively. The response time of Cr (III) ions interaction was 2 min. The lowest detection of Cr (III) by Au-Ag/CuS nanoparticles was 0.5 nM. The Au-Ag/CuS nano catalyst was applied to decomposition of drug under visible lamp irradiation. The photo degradation response of drug was 100.0% in 30 min irradiation. The particles exhibited excellent antibacterial activities.
Assuntos
Ouro , Nanopartículas Metálicas , Antibacterianos/farmacologia , Cromo , Cobre , Prata , SulfetosRESUMO
In this project, Sn-Fe bimetallic nanoparticles were prepared by a facile method. The bimetallic nanoparticles of it could be well established by a field emission scanning electron microscope micrographs. Due to the excellent synergistic influence between Sn-Fe nanoparticles and leucine indicated a great performance for determination of Cr3+. The material was characterized using the XRD, DLS, and zetasizer for theevaluation of crystal structure and morphologyinformation.The potential and effective size of Sn-Fe NPs was -29.10 mV and 30 nm, respectively. Cr3+ ions interaction with the Sn-Fe NPs-leucine probe was carried out in 1 min as response time. The limit of detection of Sn-Fe NPs for Cr(III) colorimetric method was 0.25 nM. The prepared nanoparticles showed impressive photocatalysis efficiency for degradation of MO was about 95.1% in 35 min, thus the prepared nanoparticles may be developed for the detoxification of pollution. The prepared nanoparticles depicted effective antibacterial activity againstC. botulinum and, H. pylori bacteria.
Assuntos
Nanopartículas Metálicas , Nanopartículas , Antibacterianos/farmacologia , Bactérias , Colorimetria , LeucinaRESUMO
In this project, we studied the thermal and chemical method for the synthesis of carbon dots (CDs)/Hematite (α-Fe2O3) quantum dots and the preparation of hydroxypropyl cellulose cross-linked chitosan (HPCCS) and ulvan (UN) was performed by chemical method. Carbon dots/α-Fe2O3 quantum dots with size distribution of 3-5 nm were completely encapsulated in the HPCCS/UN NPs to obtain composites, which indicated unique characteristics with respect to antimicrobial, pH-responsive and optical properties. The CDs-HQDs/HPCCS/UN nanocomposites exhibited a single-excitation (440 nm), dual-emission fluorescence property (505 nm and 628 nm for green and red light from CDs-HQDs and HPCCS/UN NPs). The nanocomposites played as a pH-responsive drug delivery process to release ulvan at a fast rate in pH 7.4 buffer solution but at a slow rate in low pH solutions. The CDs-HQDs/HPCCS/UN nanocomposites gained the highest photocatalytic activity for degrading 4-chlorophenol (4-CPh) as a pollutant (>98% during 70 min under sunlight irradiation). Moreover, the nanocomposites indicated great inhibitory influences towards bacterial and fungal.
Assuntos
Anti-Infecciosos/química , Celulose/análogos & derivados , Quitosana/química , Nanocompostos/química , Pontos Quânticos/química , Luz Solar , Anti-Infecciosos/farmacologia , Carbono/química , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Celulose/química , Clorofenóis/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Compostos Férricos/química , Humanos , Concentração de Íons de Hidrogênio , Nanocompostos/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Poluentes Químicos da Água/químicaRESUMO
The material of CuS/polyvinyl alcohol-chitosan (CuS/PVACS) was prepared with a novel synthesis analysis. The crystallinity, morphological characteristics, and photocatalytic performance of the nano-materials were investigated by X-ray diffraction, field emission scanning electron microscopy X-ray photoelectron, and UV-vis spectrophotometry. The band gap values (Eg) was found as 2.50, and 2.04 eV for CuS, and CuS/PVACS nano-catalyst, respectively. The photo-degradation amount of the malachite green solutions which were degraded by CuS/PVACS in the UV-irradiation in 60 min was above 96.51%. The antibacterial properties of the CuS/PVACS has been evaluated versus (G+/G-) bacteria. The results of antibacterial performance indicated that CuS/PVACS nanocomposites have bacteriostatic behavior versus Escherichia coli, Pseudomonas syringae, Staphylococcus aureus and Streptococcus pneumoniae.
Assuntos
Antibacterianos , Quitosana/química , Cobre/química , Nanocompostos/química , Álcool de Polivinil/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Catálise , Fotólise , Purificação da ÁguaRESUMO
Development of high responsive photocatalysts for the degradation of dye from water is a significance method to solve the difficulties of water contamination. In the present project, Cr2O3 nanoparticles were decorated onto cellulose through a facile synthesis method, which was exposed to characterization by XRD, FESEM, DLS, PL, and UV-vis spectroscopy. The structural attributes confirmed the presence of rhombohedral phase of Cr2O3 nanoparticles. The mean crystal size of Cr2O3, and Cr2O3/cellulose nanocomposites were 38.50 nm, and 50.11 nm, respectively. The band gap values (Eg) of Cr2O3, and Cr2O3/cellulose nanocomposites were was found 3.00, and 2.53 eV, respectively. Moreover, the morphological and optical studies have been showed the impressive photocatalytic properties of the prepared Cr2O3/cellulose nanocomposites. The photocatalytic efficiency of Cr2O3, and Cr2O3/cellulose nanocomposites has been investigated for the photo-degradation of crystal violet in the ultraviolet light region. The Cr2O3/cellulose indicated promising photocatalytic performance and up to 99.65% of the crystal violet was photo-degraded in 40 min. The obtained crystal violet degradation results were fitted onto a Langmuir-Hinshelwood (L-H) plot. The antioxidant performances of Cr2O3, and Cr2O3/cellulose were analyzed. The beneficial antibacterial performance of the Cr2O3/cellulose nanocomposites was tested by various bacteria as Escherichia coli, Pseudomonas aeruginosa, staphylococcus aurous, and Streptococcus pyogenes.
Assuntos
Antibacterianos , Antioxidantes , Celulose , Compostos de Cromo , Nanocompostos , Antibacterianos/administração & dosagem , Antibacterianos/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Compostos de Bifenilo/química , Catálise , Celulose/administração & dosagem , Celulose/química , Compostos de Cromo/administração & dosagem , Compostos de Cromo/química , Corantes/química , Violeta Genciana/química , Nanocompostos/administração & dosagem , Nanocompostos/química , Picratos/química , Poluentes Químicos da Água/químicaRESUMO
Silver sulfidemagnesium oxide/graphene oxide (Ag2S-MgO/GO) nanocomposite was prepared via sol-gel/ultrasound method to modify the photo-degradation performance for rhodamine B decontamination under visible and UV light. Analytical studies were performed to distinguish the properties such as structure, morphology, and elements of prepared materials. The average crystallite size of MgO, Ag2S-MgO and Ag2S-MgO/GO is distinguished to be 24.2, 29.3 and 33.1 nm, respectively. The Band gap MgO, Ag2S-MgO and Ag2S-MgO/GO is 4.08, 3.25 and 2.82 eV, respectively. Ag2S-MgO/GO nanocomposites illustrated the highest photo-degradation rate of rhodamine B (RhB) under UV light (98.8%) and visible light (64.8%) during in 60 min. In this project, the process parameter of pH and time were investigated for RhB degradation activity influence. The suggested mechanisms for the enhanced photo-degradation of RhB by Ag2S-MgO/GO nanocomposites under light irradiation due to enhanced charge transfer efficiency via decreasing band gap amount; reduced e-/h+ recombination of MgO with the Ag2S crystal and an enhanced removal efficiency with the supported on graphene oxide. Examination of the antibacterial and antifungal properties of the prepared nano-materials were conducted with Bacillus vallismortis, Escherichia coli, Aspergillus flavus and Trichoderma viride. The beneficial antibacterial and antifungal performance of the Ag2S-MgO/GO nanocomposites was further tested by a great reduction in the number of bacteria and fungi medium with the addition of the Ag2S-MgO/GO nanocomposites.
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Anti-Infecciosos/química , Grafite/química , Óxido de Magnésio/química , Nanocompostos/química , Compostos de Prata/química , Bacillus/efeitos dos fármacos , Catálise , Escherichia coli/efeitos dos fármacos , Luz , Processos Fotoquímicos , Rodaminas/química , Relação Estrutura-Atividade , Propriedades de Superfície , Fatores de TempoRESUMO
In this project, we have prepared a nanostructure of CeO2 nanorods, CoS2-CeO2, and CoS2-CeO2/cellulose-chitosan (CSCS) nanocomposites by ultrasonic method. This nanostructure was characterized using XRD, DLS, field emission scanning microscopy/EDS, DLS, UV-vis DRS, and PL spectrophotometer for determination of crystalline status, morphological, and bandgap data. Both the CeO2 and CoS2 show crystalâ¯structure with cubic and pyrite phase. It was found to be the crystal size of CeO2 nanorods, CoS2-CeO2 and CoS2-CeO2/CSCS were 56.19 nm, 62.11 nm, and 65.14 nm, respectively. The photocatalytic activity of CeO2 nanorods, CoS2-CeO2, and CoS2-CeO2/CSCS nanocomposites was evaluated with the photo-degradation of 4-nitrophenol (4NP) as a toxic organic pollutant under UV light irradiation. The 4NP photo-degradation amount reached 95.42% after 60 min UV light irradiation for CoS2-CeO2/CSCS nanocomposites due to the band gap data of CoS2-CeO2/CSCS was lower than other catalyst and photocatalytic modification process. The antimicrobial data indicated the significant properties of CoS2-CeO2/CSCS nanocomposites for this study.