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1.
Environ Res ; 252(Pt 3): 119068, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38705452

RESUMO

Cellulose acetate membranes exhibit a potential to be applied in hemodialysis. However, their performance is limited by membrane fouling and a lack of antibacterial properties. In this research, copper oxide (I) nanoparticles were fabricated in situ into a cellulose acetate matrix in the presence of polyvinylpyrrolidone (pore-forming agent) and sulfobetaine (stabilising agent) to reduce the leakage of copper ions from nano-enhanced membranes. The influence of nanoparticles on the membrane structure and their antibacterial and antifouling properties were investigated. The results showed that incorporating Cu2O NPs imparted significant antibacterial properties against Staphylococcus aureus and fouling resistance under physiological conditions. The Cu2O NPs-modified membrane could pave the way for potential dialysis applications.


Assuntos
Antibacterianos , Incrustação Biológica , Celulose , Cobre , Membranas Artificiais , Staphylococcus aureus , Celulose/análogos & derivados , Celulose/química , Celulose/farmacologia , Cobre/química , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Nanopartículas/química , Nanopartículas Metálicas/química , Povidona/química , Povidona/análogos & derivados
2.
Proc Natl Acad Sci U S A ; 117(27): 15473-15481, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571948

RESUMO

The development of sustainable methods for the degradation of pollutants in water is an ongoing critical challenge. Anthropogenic organic micropollutants such as pharmaceuticals, present in our water supplies in trace quantities, are currently not remediated by conventional treatment processes. Here, we report an initial demonstration of the oxidative degradation of organic micropollutants using specially designed nanoparticles and visible-wavelength sunlight. Gold "Janus" nanorods (Au JNRs), partially coated with silica to enhance their colloidal stability in aqueous solutions while also maintaining a partially uncoated Au surface to facilitate photocatalysis, were synthesized. Au JNRs were dispersed in an aqueous solution containing peroxydisulfate (PDS), where oxidative degradation of both simulant and actual organic micropollutants was observed. Photothermal heating, light-induced hot electron-driven charge transfer, and direct electron shuttling under dark conditions all contribute to the observed oxidation chemistry. This work not only provides an ideal platform for studying plasmonic photochemistry in aqueous medium but also opens the door for nanoengineered, solar-based methods to remediate recalcitrant micropollutants in water supplies.


Assuntos
Nanopartículas Metálicas/efeitos da radiação , Fotólise/efeitos da radiação , Luz Solar , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Ouro/química , Ouro/efeitos da radiação , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Nanotubos/química , Nanotubos/efeitos da radiação , Compostos Orgânicos/química , Compostos Orgânicos/toxicidade , Oxirredução/efeitos da radiação , Dióxido de Silício/química , Dióxido de Silício/efeitos da radiação , Água/química , Poluentes Químicos da Água/toxicidade
3.
Mikrochim Acta ; 190(5): 199, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140766

RESUMO

A reliable and brief ultralow fouling electrochemical sensing system capable of monitoring targets in complex biological media was constructed and validated based on gold nanoparticles-peptide hydrogel-modified screen-printed electrode. The self-assembled zwitterionic peptide hydrogel was prepared by a newly designed peptide sequence of Phe-Phe-Cys-Cys-(Glu-Lys)3 with the N-terminal modified with a fluorene methoxycarbonyl group. The thiol groups on cysteine of the designed peptide are able to self-assemble with AuNPs to form a three-dimensional nanonetwork structure, which showed satisfactory antifouling capability in complex biological media (human serum). The developed gold nanoparticles-peptide hydrogel-based electrochemical sensing platform displayed notably sensing properties for dopamine determination, with a wide linear range (from 0.2 nM to 1.9 µM), a low limit of detection (0.12 nM), and an excellent selectivity. This highly sensitive and ultralow fouling electrochemical sensor was fabricated via simple preparation with concise components that avoid the accumulation of layers with single functional material and complex activation processes. This ultralow fouling and highly sensitive strategy based on the gold nanoparticles-peptide hydrogel with a three-dimensional nanonetwork offers a solution to the current situation of various low-fouling sensing systems facing impaired sensitivity and provides a potential path for the practical application of electrochemical sensors.


Assuntos
Incrustação Biológica , Nanopartículas Metálicas , Humanos , Dopamina/análise , Ouro/química , Nanopartículas Metálicas/química , Hidrogéis , Incrustação Biológica/prevenção & controle , Peptídeos/química
4.
Molecules ; 28(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36615605

RESUMO

Hazardous dyes in industrial wastewater are an internationally recognized issue for community health. Nanoparticles synthesized through green protocols are a fascinating research field with numerous applications. The current study mainly aimed to investigate the degradation of Congo red (CR) dye under UV light in the presence of H2O2 and the photocatalytic activity of copper oxide nanoparticles (CuONPs). For CuONP formation, Citrus maxima extract contains a high number of phytochemical constituents. The size of CuONPs ranges between 25 and 90 nm. The photocatalytic activity of CuONPs with the addition of H2O2 was observed and analyzed under UV light to eliminate CR dye. The UV light caused the decomposition of H2O2, which produced ·OH radicals. The results revealed a significant increment in dye degradation during the presence of H2O2. The effect of concentration on the degradation of the CR dye was also studied. The degradation pathway of organic pollutants was reputable from the hydroxy radical medicated degradation of CR. Advanced Oxidation Treatment depends on the in situ production of reactive ·OH species and is presented as the most effective procedure for decontamination. The biological activity of CuONPs was evaluated against Escherichia coli Bacillus subtillis, Staphylococcus aureus, Shigella flexenari, Acinetobacter Klebsiella pneumonia, Salmonella typhi and Micrococcus luteus. The newly synthesised nanomaterials showed strong inhibition activity against Escherichia coli (45%), Bacillus subtilis (42%) and Acinetobacter species (25%). The activity of CuONPs was also investigated against different fungus species such as: Aspergillus flavus, A. niger, Candida glabrata, T. longifusus, M. Canis, C. glabrata and showed a good inhibition zone against Candida glabrata 75%, Aspergillus flavus 68%, T. longifusus 60%. The materials showed good activity against C. glaberata, A. flavus and T. longifusus. Furthermore, CuONPs were tested for antioxidant properties using 2, 2 diphenyl-1-picrylhydrazyl) (DPPH).


Assuntos
Vermelho Congo , Nanopartículas Metálicas , Peróxido de Hidrogênio/farmacologia , Raios Ultravioleta , Nanopartículas Metálicas/química , Corantes/química , Escherichia coli , Antibacterianos/farmacologia
5.
Nano Lett ; 21(1): 337-343, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33227203

RESUMO

Since the emergence of the COVID-19 pandemic outbreak, the increasing demand and disposal of surgical masks has resulted in significant economic costs and environmental impacts. Here, we applied a dual-channel spray-assisted nanocoating hybrid of shellac/copper nanoparticles (CuNPs) to a nonwoven surgical mask, thereby increasing the hydrophobicity of the surface and repelling aqueous droplets. The resulting surface showed outstanding photoactivity (combined photocatalytic and photothermal properties) for antimicrobial action, conferring reusability and self-sterilizing ability to the masks. Under solar illumination, the temperature of this photoactive antiviral mask (PAM) rapidly increased to >70 °C, generating a high level of free radicals that disrupted the membrane of nanosized (∼100 nm) virus-like particles and made the masks self-cleaning and reusable. This PAM design can provide significant protection against the transmission of viral aerosols in the fight against the COVID-19 pandemic.


Assuntos
Antivirais/química , COVID-19/prevenção & controle , Cobre/química , Máscaras/virologia , Nanopartículas Metálicas/química , Esterilização/métodos , Catálise , Humanos , Interações Hidrofóbicas e Hidrofílicas , Processos Fotoquímicos , SARS-CoV-2/isolamento & purificação , Temperatura
6.
Molecules ; 26(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770799

RESUMO

Biofilm formation is an important virulence factor for the opportunistic microorganisms that elicit skin infections. The recalcitrant feature of biofilms and their antibiotic tolerance impose a great challenge on the use of conventional therapies. Most antibacterial agents have difficulty penetrating the matrix produced by a biofilm. One novel approach to address these concerns is to prevent or inhibit the formation of biofilms using nanoparticles. The advantages of using nanosystems for antibiofilm applications include high drug loading efficiency, sustained or prolonged drug release, increased drug stability, improved bioavailability, close contact with bacteria, and enhanced accumulation or targeting to biomasses. Topically applied nanoparticles can act as a strategy for enhancing antibiotic delivery into the skin. Various types of nanoparticles, including metal oxide nanoparticles, polymeric nanoparticles, liposomes, and lipid-based nanoparticles, have been employed for topical delivery to treat biofilm infections on the skin. Moreover, nanoparticles can be designed to combine with external stimuli to produce magnetic, photothermal, or photodynamic effects to ablate the biofilm matrix. This study focuses on advanced antibiofilm approaches based on nanomedicine for treating skin infections. We provide in-depth descriptions on how the nanoparticles could effectively eliminate biofilms and any pathogens inside them. We then describe cases of using nanoparticles for antibiofilm treatment of the skin. Most of the studies included in this review were supported by in vivo animal infection models. This article offers an overview of the benefits of nanosystems for treating biofilms grown on the skin.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Pele/microbiologia , Nanomedicina Teranóstica , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas/química , Dermatopatias/tratamento farmacológico , Dermatopatias/etiologia , Dermatopatias/patologia , Resultado do Tratamento
8.
Eur J Orthod ; 39(1): 9-16, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26787659

RESUMO

INTRODUCTION: Silver nanoparticles are currently utilized in the fields of dentistry. The aim of this study was to evaluate the antibacterial properties and ion release of nanosilver coated orthodontic brackets compared to conventional brackets. METHODS: Nanosilver coating process was applied to standard orthodontic brackets placed on the mandibular incisors of Wistar Albino rats in the study group and conventional brackets in the control group. Dental plaque, mucosal vestibular smears, saliva, and blood samples were collected from rats at various days. The amounts of nanosilver ions in blood and saliva were measured and microbiological evaluation was made for Streptococcus mutans. For testing cariogenicity, all rats were sacrificed at the end of 75 days under anaesthesia. Teeth were stained using a caries indicator, then the caries ratio was assessed. RESULTS: Nanosilver coated orthodontic bracket favoured the inhibition of S.mutans on Day 30 and reduction of caries on the smooth surfaces. The nanosilver amounts in the saliva and serum samples were significantly higher in the study group on Day 7. CONCLUSION: It is suggested that nanosilver coated orthodontic brackets, as an antibacterial agent without patient compliance, could be helpful for the prevention of white spot lesions during fixed orthodontic treatment.


Assuntos
Antibacterianos/farmacologia , Cárie Dentária/prevenção & controle , Placa Dentária/microbiologia , Nanopartículas Metálicas/química , Braquetes Ortodônticos/microbiologia , Saliva/microbiologia , Prata/química , Streptococcus mutans/fisiologia , Animais , Antibacterianos/química , Humanos , Masculino , Ratos , Ratos Wistar
9.
Ecotoxicol Environ Saf ; 132: 318-28, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27344400

RESUMO

Mosquitoes are arthropods of huge medical and veterinary relevance, since they vector pathogens and parasites of public health importance, including malaria, dengue and Zika virus. Currently, nanotechnology is considered a potential eco-friendly approach in mosquito control research. We proposed a novel method of biofabrication of silver nanoparticles (AgNP) using chitosan (Ch) from crab shells. Ch-AgNP nanocomposite was characterized by UV-vis spectroscopy, FTIR, SEM, EDX and XRD. Ch-AgNP were tested against larvae and pupae of the malaria vector Anopheles stephensi obtaining LC50 ranging from 3.18 ppm (I) to 6.54 ppm (pupae). The antibacterial properties of Ch-AgNP were proved against Bacillus subtilis, Klebsiella pneumoniae and Salmonella typhi, while no growth inhibition was reported in assays conducted on Proteus vulgaris. Concerning non-target effects, in standard laboratory considtions the predation efficiency of Danio rerio zebrafishes was 68.8% and 61.6% against I and II instar larvae of A. stephensi, respectively. In a Ch-AgNP-contaminated environment, fish predation was boosted to 89.5% and 77.3%, respectively. Quantitative analysis of antioxidant enzymes SOD, CAT and LPO from hepatopancreas of fresh water crabs Paratelphusa hydrodromous exposed for 16 days to a Ch-AgNP-contaminated aquatic environment were conducted. Notably, deleterious effects of Ch-AgNP contaminating aquatic enviroment on the non-target crab P. hydrodromous were observed, particularly when doses higher than 8-10ppm are tested. Overall, this research highlights the potential of Ch-AGNP for the development of newer control tools against young instar populations of malaria mosquitoes, also highlighting some risks concerned the employ of nanoparticles in aquatic environments.


Assuntos
Anopheles , Quitosana/síntese química , Inseticidas/síntese química , Nanopartículas Metálicas/química , Prata/química , Animais , Braquiúros , Humanos , Larva/efeitos dos fármacos , Malária/prevenção & controle , Controle de Mosquitos , Pupa/efeitos dos fármacos
10.
Angew Chem Int Ed Engl ; 55(36): 10732-6, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27484616

RESUMO

Extracellular DNA (eDNA) is an essential structural component during biofilm formation, including initial bacterial adhesion, subsequent development, and final maturation. Herein, the construction of a DNase-mimetic artificial enzyme (DMAE) for anti-biofilm applications is described. By confining passivated gold nanoparticles with multiple cerium(IV) complexes on the surface of colloidal magnetic Fe3 O4 /SiO2 core/shell particles, a robust and recoverable artificial enzyme with DNase-like activity was obtained, which exhibited high cleavage ability towards both model substrates and eDNA. Compared to the high environmental sensitivity of natural DNase in anti-biofilm applications, DMAE exhibited a much better operational stability and easier recoverability. When DMAE was coated on substratum surfaces, biofilm formation was inhibited for prolonged periods of time, and the DMAE excelled in the dispersion of established biofilms of various ages. Finally, the presence of DMAE remarkably potentiated the efficiency of traditional antibiotics to kill biofilm-encased bacteria and eradiate biofilms.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Materiais Biomiméticos/química , Cério/química , Complexos de Coordenação/química , Desoxirribonucleases/química , Nanopartículas Metálicas/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Materiais Biomiméticos/farmacologia , Cério/farmacologia , Complexos de Coordenação/farmacologia , Desoxirribonucleases/farmacologia , Ouro/química , Humanos , Nanopartículas Metálicas/ultraestrutura , Dióxido de Silício/química , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/fisiologia
11.
Phytopathology ; 105(9): 1183-90, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25871856

RESUMO

Application of nanoparticles for controlling plant pathogens is a rapidly emerging area in plant disease management, and nanoparticles synthesis methods that are economical and ecofriendly are extensively investigated. In this project, we investigated the potential of silver nanoparticles (AgNPs) synthesized with aqueous extract of Artemisia absinthium against several Phytophthora spp., which cause many economically important crop diseases. In in vitro dose-response tests conducted in microtiter plates, 10 µg ml⁻¹ of AgNPs inhibited mycelial growth of P. parasitica, P. infestans, P. palmivora, P. cinnamomi, P. tropicalis, P. capsici, and P. katsurae. Detailed in vitro dose-response analyses conducted with P. parasitica and P. capsici revealed that AgNPs synthesized with A. absinthium extract were highly potent (IC50: 2.1 to 8.3 µg ml⁻¹) and efficacious (100%) in inhibiting mycelial growth, zoospore germination, germ tube elongation, and zoospore production. Interestingly, AgNP treatment accelerated encystment of zoospores. Consistent with in vitro results, in planta experiments conducted in a greenhouse revealed that AgNP treatments prevented Phytophthora infection and improved plant survival. Moreover, AgNP in in planta experiments did not produce any adverse effects on plant growth. These investigations provide a simple and economical method for controlling Phytophthora with AgNP without affecting normal plant physiology.


Assuntos
Artemisia absinthium/química , Nanopartículas Metálicas/química , Phytophthora/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Extratos Vegetais/farmacologia , Prata/farmacologia , Phytophthora/crescimento & desenvolvimento , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
12.
Environ Sci Technol ; 48(1): 384-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24308843

RESUMO

Biofouling is a major operational challenge in reverse osmosis (RO) desalination, motivating a search for improved biofouling control strategies. Copper, long known for its antibacterial activity and relatively low cost, is an attractive potential biocidal agent. In this paper, we present a method for loading copper nanoparticles (Cu-NPs) on the surface of a thin-film composite (TFC) polyamide RO membrane. Cu-NPs were synthesized using polyethyleneimine (PEI) as a capping agent, resulting in particles with an average radius of 34 nm and a copper content between 39 and 49 wt.%. The positive charge of the Cu-NPs imparted by the PEI allowed a simple electrostatic functionalization of the negatively charged RO membrane. We confirmed functionalization and irreversible binding of the Cu-NPs to the membrane surface with SEM and XPS after exposing the membrane to bath sonication. We also demonstrated that Cu-NP functionalization can be repeated after the Cu-NPs dissolve from the membrane surface. The Cu-NP functionalization had minimal impact on the intrinsic membrane transport parameters. Surface hydrophilicity and surface roughness were also maintained, and the membrane surface charge became positive after functionalization. The functionalized membrane exhibited significant antibacterial activity, leading to an 80-95% reduction in the number of attached live bacteria for three different model bacterial strains. Challenges associated with this functionalization method and its implementation in RO desalination are discussed.


Assuntos
Antibacterianos/química , Incrustação Biológica/prevenção & controle , Cobre/química , Membranas Artificiais , Nanopartículas Metálicas/química , Bactérias/crescimento & desenvolvimento , Interações Hidrofóbicas e Hidrofílicas , Nylons/química , Propriedades de Superfície , Purificação da Água/instrumentação
13.
J Nanosci Nanotechnol ; 14(9): 6792-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924333

RESUMO

TiO2 and Pd doped TiO2 (Pd/TiO2) nanoparticles were prepared by sol gel method. Pd/TiO2 material was characterized by XRD, TEM, TPR, XPS and BET. From XRD data, the crystalline type of TiO2 is known to as Anatase type. TiO2 and Pd/TiO2 were in the order of 9-10 nm and 10-13 nm respectively. The photocatalytic activities of the TiO2 and Pd/TiO2 nanomaterials were evaluated and compared for the photodegradation of formaldehyde (HCHO). HCHO degradation on Pd/TiO2 catalyst, at 60 min, the degradation rate of gaseous HCHO is 95%. Using Pd/TiO2, the rate was faster than TiO2 or doped with other metals (Au/TiO2; Ag/TiO2; Pt/TiO2).


Assuntos
Formaldeído/química , Gases/química , Nanopartículas Metálicas/química , Paládio/química , Titânio/química , Formaldeído/análise , Gases/análise , Luz , Fotólise
14.
Biomed Pharmacother ; 170: 116083, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163395

RESUMO

As we navigate the modern era, the intersection of time-honoured natural remedies and contemporary scientific approaches forms a burgeoning frontier in global healthcare. For generations, natural products have been foundational to health solutions, serving as the primary healthcare choice for 80% to 85% of the world's population. These herbal-based, nature-derived substances, significant across diverse geographies, necessitate a renewed emphasis on enhancing their quality, efficacy, and safety. In the current century, the advent of biogenic phytonanoparticles has emerged as an innovative therapeutic conduit, perfectly aligning with principles of environmental safety and scientific ingenuity. Utilizing green chemistry techniques, a spectrum of metallic nanoparticles including elements such as copper, silver, iron, zinc, and titanium oxide can be produced with attributes of non-toxicity, sustainability, and economic efficiency. Sophisticated herb-mediated processes yield an array of plant-originated nanomaterials, each demonstrating unique physical, chemical, and biological characteristics. These attributes herald new therapeutic potentials, encompassing antioxidants, anti-aging applications, and more. Modern technology further accelerates the synthesis of natural products within laboratory settings, providing an efficient alternative to conventional isolation methods. The collaboration between traditional wisdom and advanced methodologies now signals a new epoch in healthcare. Here, the augmentation of traditional medicine is realized through rigorous scientific examination. By intertwining ethical considerations, cutting-edge technology, and natural philosophy, the realms of biogenic phytonanoparticles and traditional medicine forge promising pathways for research, development, and healing. The narrative of this seamless integration marks an exciting evolution in healthcare, where the fusion of sustainability and innovation crafts a future filled with endless possibilities for human well-being. The research in the development of metallic nanoparticles is crucial for unlocking their potential in revolutionizing fields such as medicine, catalysis, and electronics, promising groundbreaking applications with enhanced efficiency and tailored functionalities in future technologies. This exploration is essential for harnessing the unique properties of metallic nanoparticles to address pressing challenges and advance innovations across diverse scientific and industrial domains.


Assuntos
Nanopartículas Metálicas , Extratos Vegetais , Humanos , Extratos Vegetais/química , Química Verde , Plantas , Medicina Tradicional , Nanopartículas Metálicas/química , Atenção à Saúde
15.
IET Nanobiotechnol ; 2024: 5538107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863968

RESUMO

Materials and Methods: This study followed the PRISMA reporting guidelines to present the results. A comprehensive search was performed on electronic databases such as PubMed, Scopus, Web of Sciences, and Science Direct. Initially, 413 articles were retrieved. After removing duplicates and applying specific inclusion and exclusion criteria, 10 articles were finally included in this systematic review. Results: The reviewed studies showed that selenium nanoparticles had anti-inflammatory and antioxidant properties. They effectively protected the kidneys, liver, and testicles from damage. Furthermore, there was evidence of efficient radioprotection for the organs examined without significant side effects. Conclusions: This systematic review emphasizes the potential advantages of using selenium nanoparticles to prevent the negative effects of ionizing radiation. Importantly, these protective effects were achieved without causing noticeable side effects. These findings suggest the potential role of selenium nanoparticles as radioprotective agents, offering possible therapeutic applications to reduce the risks related to ionizing radiation exposure in medical imaging and radiotherapy procedures.


Assuntos
Protetores contra Radiação , Selênio , Selênio/química , Selênio/farmacologia , Protetores contra Radiação/química , Protetores contra Radiação/farmacologia , Animais , Humanos , Antioxidantes/química , Antioxidantes/farmacologia , Nanopartículas/química , Nanopartículas Metálicas/química , Lesões por Radiação/prevenção & controle
16.
Environ Sci Pollut Res Int ; 31(21): 30988-31000, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38622420

RESUMO

In this study, a facile method for multifunctional surface modification on forward osmosis (FO) membrane was constructed by surface immobilization of AgNPs based on tannic acid (TA)/diethylenetriamine (DETA) precursor layer. The cellulose triacetate (CTA) FO membranes modified by TA and DETA with different co-deposition time (6 h, 12 h, 24 h) were investigated. Results indicated that the TA/DETA (24)-Ag CTA membrane with a TA/DETA co-deposition time of 24 h was identified to be optimal, which attained more hydrophilic. And it had the bacterial mortality of Escherichia coli and Staphylococcus aureus reaching 98.23% and 99.83% respectively and possessed excellent physical and chemical binding stability. Meanwhile, the coating layer resulted in the antifouling ability without damaging the membrane intrinsic transport characteristics. As for synthetic municipal wastewater treatment, the water flux of CTA FO membrane decreased approximately 49% of the initial flux after running for 14 days. In contrast, the flux decline rate of TA/DETA (24)-Ag CTA membrane was about 37%. Furthermore, less foulant deposition and higher recovery rate of water flux was observed for TA/DETA (24)-Ag CTA membrane, implying that the modified membrane effectively alleviated membrane fouling and processed a lower flux decline during municipal wastewater treatment. It was attributed to the enhanced surface hydrophilicity and antibacterial property of the coating layer, which improved antifouling property.


Assuntos
Nanopartículas Metálicas , Prata , Taninos , Águas Residuárias , Purificação da Água , Taninos/química , Águas Residuárias/química , Prata/química , Nanopartículas Metálicas/química , Purificação da Água/métodos , Osmose , Membranas Artificiais , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Incrustação Biológica/prevenção & controle
17.
Biomolecules ; 12(7)2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35883489

RESUMO

In recent years, the study of metal complexes and metal-based nanomaterials has aroused particular interest, leading to the promotion of new effective systems for the abatement of various viral diseases. Starting from the analysis of chemical properties, this review focuses on the employment of metal-based nanoparticles as antiviral drugs and how this interaction leads to a substantial enhancement in antiviral activity. The use of metal-based antiviral drugs has also spread for the formulation of antiviral vaccines, thanks especially to the remarkable adjuvant activities of some of the metal complexes. In particular, the small size and inert nature of Au- and Ag-based nanoparticles have been exploited for the design of systems for antiviral drug delivery, leading to the development of specific and safe therapies that lead to a decrease in side effects.


Assuntos
Complexos de Coordenação , Nanopartículas Metálicas , Antivirais/farmacologia , Antivirais/uso terapêutico , Complexos de Coordenação/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Preparações Farmacêuticas
18.
Pest Manag Sci ; 78(10): 3953-3956, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35620887

RESUMO

Chemical control suffers from the loss of available conventional active ingredients due to strict environmental safety regulations which, combined with the loss of fungicide efficacy due to resistance development, constitute major problems of contemporary crop protection. Metal-containing nanoparticles (MNPs) appear to have all the credentials to be next-generation, eco-compatible fungicide alternatives and a valuable anti-resistance management tool. Could the introduction of MNPs as nano-fungicides be the answer to both reducing the environmental footprint of xenobiotics and dealing with fungicide resistance? The potential of MNPs to be utilized as nano-fungicides, both as alternatives to conventional fungicides or/and as partners in combating fungicide resistance, is discussed in terms of effectiveness, potential antimicrobial mechanisms as well as synergy profiles with conventional fungicides. However, their "golden" potential to be used both as alternatives and partners of conventional fungicides to combat resistance and reduce environmental pollution is challenged by undesirable effects towards non-target organisms such as phytotoxicity, toxicity to humans and environmental ecotoxicity, constituting risks that should be considered before their commercial introduction as nano-pesticides at a large scale. © 2022 Society of Chemical Industry.


Assuntos
Fungicidas Industriais , Nanopartículas Metálicas , Praguicidas , Proteção de Cultivos , Fungicidas Industriais/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Doenças das Plantas/prevenção & controle
19.
ACS Nano ; 15(8): 12655-12686, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34346204

RESUMO

Agrochemicals have supported the development of the agricultural economy and national population over the past century. However, excessive applications of agrochemicals pose threats to the environment and human health. In the last decades, nanoparticles (NPs) have been a hot topic in many fields, especially in agriculture, because of their physicochemical properties. Nevertheless, the prevalent methods for fabricating NPs are uneconomical and involve toxic reagents, hindering their extensive applications in the agricultural sector. In contrast, inspired by biological exemplifications from microbes and plants, their extract and biomass can act as a reducing and capping agent to form NPs without any toxic reagents. NPs synthesized through these bioinspired routes are cost-effective, ecofriendly, and high performing. With the development of nanotechnology, biosynthetic NPs (bioNPs) have been proven to be a substitute strategy for agrochemicals and traditional NPs in heavy-metal remediation of soil, promotion of plant growth, and management of plant disease with less toxicity and higher performance. Therefore, bioinspired synthesis of NPs will be an inevitable trend for sustainable development in agricultural fields. This critical review will demonstrate the bioinspired synthesis of NPs and discuss the influence of bioNPs on agricultural soil, crop growth, and crop diseases compared to chemical NPs or agrochemicals.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Humanos , Nanotecnologia/métodos , Agricultura , Agroquímicos , Solo , Nanopartículas Metálicas/química
20.
Parasit Vectors ; 13(1): 624, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33353560

RESUMO

BACKGROUND: Free-living amoebae of the genus Acanthamoeba are cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known as Acanthamoeba keratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective against Acanthamoeba trophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions. METHODS: The anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test using P < 0.05 as the level of statistical significance. RESULTS: We show that the NPs enhance the anti-Acanthamoeba activities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers. CONCLUSIONS: The conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.


Assuntos
Ceratite por Acanthamoeba/prevenção & controle , Acanthamoeba castellanii/efeitos dos fármacos , Soluções para Lentes de Contato/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Taninos/farmacologia , Animais , Humanos
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