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1.
Small ; 20(21): e2306865, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38126669

RESUMEN

Functional inks enable manufacturing of flexible electronic devices by means of printing technology. Silver nanoparticle (Ag NP) ink is widely used for printing conductive components. A sintering process is required to obtain sufficient conductivity. Thermal sintering is the most commonly used method, but the heat must be carefully applied to avoid damaging low-temperature substrates such as polymer films. In this work, two alternative sintering methods, damp heat sintering and water sintering are systematically investigated for inkjet-printed Ag tracks on polymer substrates. Both methods allow sintering polyvinyl pyrrolidone (PVP) capped Ag NPs at 85°C. In this way, the resistance is significantly reduced to only 1.7 times that of the samples on polyimide sintered in an oven at 250°C. The microstructure of sintered Ag NPs is analyzed. Taking the states of the capping layer under different conditions into account, the explanation of the sintering mechanism of Ag NPs at low temperatures is presented. Overall, both damp heat sintering and water sintering are viable options for achieving high conductivity of printed Ag tracks. They can broaden the range of substrates available for flexible electronic device fabrication while mitigating substrate damage risks. The choice between them depends on the specific application and the substrate used.

2.
Microb Pathog ; 190: 106613, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38484919

RESUMEN

This research paper presents a novel approach to the green synthesis of silver nanoparticles (AgNPs) using viticultural waste, allowing to obtain NP dispersions with distinct properties and morphologies (monodisperse and polydisperse AgNPs, referred to as mAgNPs and pAgNPs) and to compare their biological activities. Our synthesis method utilized the ethanolic extract of Vitis vinifera pruning residues, resulting in the production of mAgNPs and pAgNPs with average sizes of 12 ± 5 nm and 19 ± 14 nm, respectively. Both these AgNPs preparations demonstrated an exceptional stability in terms of size distribution, which was maintained for one year. Antimicrobial testing revealed that both types of AgNPs inhibited either the growth of planktonic cells or the metabolic activity of biofilm sessile cells in Gram-negative bacteria and yeasts. No comparable activity was found towards Gram-positives. Overall, pAgNPs exhibited a higher antimicrobial efficacy compared to their monodisperse counterparts, suggesting that their size and shape may provide a broader spectrum of interactions with target cells. Both AgNP preparations showed no cytotoxicity towards a human keratinocyte cell line. Furthermore, in vivo tests using a silkworm animal model indicated the biocompatibility of the phytosynthesized AgNPs, as they had no adverse effects on insect larvae viability. These findings emphasize the potential of targeted AgNPs synthesized from viticultural waste as environmentally friendly antimicrobial agents with minimal impact on higher organisms.


Asunto(s)
Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Plata , Vitis , Plata/farmacología , Plata/química , Plata/metabolismo , Nanopartículas del Metal/química , Animales , Humanos , Vitis/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Tamaño de la Partícula , Tecnología Química Verde , Bacterias Gramnegativas/efectos de los fármacos , Bombyx , Biopelículas/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Larva/efectos de los fármacos , Levaduras/efectos de los fármacos
3.
Nanotechnology ; 35(35)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38806018

RESUMEN

Nanotechnology has gained immense popularity and observed rapid development due to the remarkable physio-chemical properties of nanoparticles (NPs) and related nanomaterials. The green production of NPs has many benefits over traditional techniques because the current procedures are expensive, time-consuming, and involve harmful substances that limit their applicability. This study aimed to use a novel green source, theSalsola imbricata(SI) plant, which is commonly found in Central Asia and known for its medicinal properties as a reducing and stabilizing agent for the synthesis of AgNPs. The current study also utilized efficient statistical design, the Plackett-Burman Design (PBD) of Experiment method to synthesize the NPs. The characterization of NPs was carried out using UV-Vis spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy (SEM). The PBD results showed that only two out of four factorsi.e.AgNO3concentration and incubation time, were significant for the synthesis of SI-AgNPs. While remaining factors, incubation temperature and plant extract: AgNO3ratio were non-significant. The SEM analysis result showed that SI-AgNPs had a size of 20-50 nm. The SI-AgNPs demonstrated strong antibacterial activity against oral pathogens such asS. mutans and Lactobacillus acidophilus, with the highest efficacy observed at a concentration of 2 mg ml-1. The addition of SI-AgNPs in glass ionomer cement significantly increased the antibacterial activity of GIC againstS. mutans. Based on the results of the current study, the plant based AgNPs can be further evaluated in detail as alternate antimicrobial agent either alone or in combination with other antimicrobial agents for different dental applications.


Asunto(s)
Antibacterianos , Cementos de Ionómero Vítreo , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plata , Streptococcus mutans , Plata/química , Plata/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Nanopartículas del Metal/química , Cementos de Ionómero Vítreo/química , Cementos de Ionómero Vítreo/farmacología , Streptococcus mutans/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Lactobacillus acidophilus/efectos de los fármacos , Tecnología Química Verde/métodos , Espectroscopía Infrarroja por Transformada de Fourier
4.
Mol Biol Rep ; 51(1): 633, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724835

RESUMEN

BACKGROUND: Radiation therapy is utilized for treatment of localized prostate cancer. Nevertheless, cancerous cells frequently develop radiation resistance. While higher radiation doses have not always been effective, radiosensitizers have been extensively studied for their ability to enhance the cytotoxic effects of radiation. So, this study aims to evaluate the possible radiosensitization effects of docetaxel (DTX) and silver nanoparticles (SNP) in LNCaP cells. METHODS: The cytotoxic effects of DTX, SNP and 2 Gy of X-Ray radiation treatments were assessed in human LNCaP cell line using the MTT test after 24 h. Moreover, the effects of DTX, SNP and radiation on Epidermal growth factor (EGF), Caspase 3, inducible nitric oxide synthase and E-cadherin gene expression were analyzed using the Real-time PCR method. The level of Hydrogen peroxide (H2O2), an oxidative stress marker, was also detected 24 h after various single and combined treatments. RESULTS: The combinations of SNP (in low toxic concentration) and/or DTX (0.25× IC50 and 0.5 × IC50 concentrations for triple and double combinations respectively) with radiation induced significant cytotoxicity in LNCaP cells in comparison to monotherapies. These cytotoxic effects were associated with the downregulation of EGF mRNA. Additionally, H2O2 levels increased after Radiation + SNP + DTX triple combination and double combinations including Radiation + SNP and Radiation + DTX versus single treatments. The triple combination treatment also increased Caspase 3 and and E-cadherin mRNA levels in compared to single treatments in LNCaP cells. CONCLUSION: Our results indicate that the combination of SNP and DTX with radiation induces significant anti-cancer effects. Upregulation of Caspase 3 and E-cadherin gene expression, and decreased mRNA expression level of EGF may be exerted specifically by use of this combination versus single treatments.


Asunto(s)
Docetaxel , Nanopartículas del Metal , Neoplasias de la Próstata , Fármacos Sensibilizantes a Radiaciones , Plata , Humanos , Docetaxel/farmacología , Masculino , Plata/farmacología , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/genética , Línea Celular Tumoral , Fármacos Sensibilizantes a Radiaciones/farmacología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Peróxido de Hidrógeno/farmacología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Caspasa 3/metabolismo , Caspasa 3/genética , Antineoplásicos/farmacología , Factor de Crecimiento Epidérmico/metabolismo , Factor de Crecimiento Epidérmico/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Cadherinas/metabolismo , Cadherinas/genética
5.
Anal Bioanal Chem ; 416(4): 1047-1056, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38095682

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) is a highly sensitive and reliable fingerprinting technique. However, its analytical capability is closely related to the quality of a SERS substrate used for the analysis. In particular, conventional colloidal substrates possess disadvantages in terms of controllability, stability, and reproducibility, which limit their application. In order to address these issues, a simple, cost-effective, and efficient SERS substrate based on silver nanoparticle arrays (Ag NPAs) and sandpaper-molded polydimethylsiloxane (SMP) was proposed in this work. Successfully prepared via template lithography and liquid-liquid interface self-assembly (LLISA), the substrate can be applied to the specific detection of organic dyes in the environment. The substrate exhibited good SERS performance, and the limit of detection (LOD) of rhodamine 6G (R6G) was shown to be 10-7 M under the optimal conditions (1000 grit sandpaper) with a relative standard deviation (RSD) of 7.76%. Moreover, the SERS signal intensity was maintained at 60% of the initial intensity after the substrate was stored for 30 days. In addition, the Ag NPAs/SMP SERS substrate was also employed to detect crystal violet (CV) and methylene blue (MB) with the LODs of 10-6 M and 10-7 M, respectively. In summary, the Ag NPAs/SMP SERS substrate prepared in this study has great potential for the detection of organic dyes in ecological environments.

6.
Drug Resist Updat ; 68: 100935, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36774747

RESUMEN

To develop next-generation nanomedicine, theranostic nanotherapeutic strategies are increasingly being emphasized. In recent years, it is observed that the effective lifetime of anti-bacterial and anti-cancer agent is diminishing, which undermines the economic incentives necessary for clinical development and therapeutic applications. Thus, novel formulations ought to not only kill drug resistant strains and cancerous cells but also inhibit their formation. Recently, metallic nanoparticles [for example- silver (Ag) nanoparticles] have been widely investigated for their biomedical applications. The so-called applications necessitate the inclusion of these nanoparticles inside polymeric matrices (for example- dendrimer) leading to chemical functionalization of the metallic nanoparticles. Silver and silver nanoparticles' antibacterial activity has already been well established over years. Dendrimers due to their homogeneous highly branched structure and uniform composition are perfectly suitable for the inclusion of silver nanoparticles [Ag NPs]. Recently, the increasing trend in the development of Ag-dendrimer nanocomposites is attributed to the excellent antibacterial activity of Ag as well as dendrimer's unique properties like variable functional terminal ends and potential antibacterial effect necessarily. This review provides an informative overview regarding the numerous aspects of bactericidal and other biomedical applications of Ag-dendrimer nanocomposites, particularly emphasizing analysis of existing research and prospective worth to the pharmaceutical sector in future.


Asunto(s)
Dendrímeros , Nanopartículas del Metal , Nanocompuestos , Humanos , Nanopartículas del Metal/química , Plata/farmacología , Plata/química , Estudios Prospectivos , Nanocompuestos/química , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias
7.
Regul Toxicol Pharmacol ; 151: 105653, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825064

RESUMEN

Despite two decades of research on silver nanoparticle (AgNP) toxicity, a safe threshold for exposure has not yet been established, albeit being critically needed for risk assessment and regulatory decision-making. Traditionally, a point-of-departure (PoD) value is derived from dose response of apical endpoints in animal studies using either the no-observed-adverse-effect level (NOAEL) approach, or benchmark dose (BMD) modeling. To develop new approach methodologies (NAMs) to inform human risk assessment of AgNPs, we conducted a concentration response modeling of the transcriptomic changes in hepatocytes derived from human induced pluripotent stem cells (iPSCs) after being exposed to a wide range concentration (0.01-25 µg/ml) of AgNPs for 24 h. A plausible transcriptomic PoD of 0.21 µg/ml was derived for a pathway related to the mode-of-action (MOA) of AgNPs, and a more conservative PoD of 0.10 µg/ml for a gene ontology (GO) term not apparently associated with the MOA of AgNPs. A reference dose (RfD) could be calculated from either of the PoDs as a safe threshold for AgNP exposure. The current study illustrates the usefulness of in vitro transcriptomic concentration response study using human cells as a NAM for toxicity study of chemicals that lack adequate toxicity data to inform human risk assessment.

8.
Environ Toxicol ; 39(3): 1531-1543, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38009636

RESUMEN

Cerebral ischemia and reperfusion are related to various situations like injuries after various traumas, oxidative stress, increased calcium ion, capillary hypoperfusion, microvascular hyperpermeability, leukocyte infiltration, and blood-brain barrier disruption. An antidepressant Agomelatine which is a melatonin receptor (MT1/MT2) agonist and serotonin receptor (5-HT2C) antagonist has been reported by studies to have antioxidant and anti-inflammatory effects. In our study, we aimed to detect the effects of citrate-coated silver nanoparticle-loaded agomelatine application on neurodegeneration, endoplasmic reticulum stress, autophagic and apoptotic cell death, inflammation, and P2X7R expression in the cerebral ischemia-reperfusion model to facilitate the passage of blood-brain barrier. Forty two Sprague-Dawley rats in total were divided into six equal groups (n:7) and applications were performed. Acute cerebral injury in the ischemia-reperfusion model was created 2 h after internal carotid artery ligation in rats and then at the 2nd hour of reperfusion citrate-coated silver nanoparticles loaded with Agomelatine were applied. Twenty four hours later, neurologic analysis on animals in experimental groups was performed, animals were decapitated and GSH, GPx, SOD, CAT, MDA, IL-1ß, and TNF-α parameters were examined after taking blood and the cerebral tissue samples. As a result, it was determined that ischemia-reperfusion caused endoplasmic reticulum stress in the cerebral tissues and thus caused cellular injury.


Asunto(s)
Isquemia Encefálica , Nanopartículas del Metal , Daño por Reperfusión , Ratas , Animales , Ratas Sprague-Dawley , Inflamasomas/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Plata , Ácido Cítrico/farmacología , Daño por Reperfusión/metabolismo , Estrés Oxidativo , Isquemia Encefálica/metabolismo , Citratos/farmacología , Reperfusión , Isquemia , Estrés del Retículo Endoplásmico
9.
Mikrochim Acta ; 191(5): 244, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38578321

RESUMEN

The sensing sensitivity was improved for silver nanoparticles (AgNPs)-based colorimetric biosensors by using the most suitable salt to induce AgNPs aggregation. As for the salt composed of low-affinity anion and monovalent cation, the cation-dependent charge screening effect was the driving force for AgNPs aggregation. Apart from the charge screening effect, both the bridging of multivalent cation to the surface ligand of AgNP and the interaction between anion and Ag contributed to inducing AgNPs aggregation. Considering the higher aggregation efficiency of AgNPs resulted in a narrower sensing range, salt composed of low-affinity anion and monovalent cation was recommended for AgNPs-based colorimetric analysis, which was confirmed by fourfold higher sensitivity of DNA-21 detection using NaF than NaCl. This work inspires further thinking on improving the sensing performance of metal nanomaterials-based sensors from the point of colloidal surface science.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Cloruro de Sodio , Plata , Colorimetría/métodos , Aniones , Cationes Monovalentes
10.
Int J Mol Sci ; 25(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38255786

RESUMEN

Polymer-based membranes represent an irreplaceable group of materials that can be applied in a wide range of key industrial areas, from packaging to high-end technologies. Increased selectivity to transport properties or the possibility of controlling membrane permeability by external stimuli represents a key issue in current material research. In this work, we present an unconventional approach with the introduction of silver nanoparticles (AgNPs) into membrane pores, by immobilising them onto the surface of polyethyleneterephthalate (PET) foil with subsequent physical modification by means of laser and plasma radiation prior to membrane preparation. Our results showed that the surface characteristics of AgNP-decorated PET (surface morphology, AgNP content, and depth profile) affected the distribution and concentration of AgNPs in subsequent ion-track membranes. We believe that the presented approach affecting the redistribution of AgNPs in the polymer volume may open up new possibilities for the preparation of metal nanoparticle-filled polymeric membranes. The presence of AgNPs on the pore walls can facilitate the grafting of stimuli-responsive molecules onto these active sites and may contribute to the development of intelligent membranes with controllable transport properties.


Asunto(s)
Nanopartículas del Metal , Poro Nuclear , Plata , Polímeros , Tomografía de Emisión de Positrones
11.
Water Sci Technol ; 89(9): 2483-2497, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747962

RESUMEN

In this study, a multi-functional layer was developed based on the commercially available cellulose triacetate (CTA) forward osmosis (FO) membrane to improve its antifouling property. Tannic acid/ferric ion (TA/Fe3+) complexes were firstly coated as a precursor layer on the membrane surface via self-assembly. Afterwards, the tannic acid/diethylenetriamine (TA/DETA) hydrophilic functional layer was further coated, following Ag/polyvinylpyrrolidone (PVP) anti-bacterial layer was formed in situ through the reducibility of TA to obtain TA/Fe3+-TA/DETA-Ag/PVP-modified membrane. The optimized precursor layer was acquired by adjusting the buffer solution pH to 8, TA/Fe3+ ratio to 4 and the number of self-assembled layers to 5. The permeability testing results illustrated that the functional layer had an insignificant effect on the membrane transport parameters. The TA/Fe3+-TA/DETA-Ag/PVP-modified membrane simultaneously exhibited excellent physical and chemical stability. The coated membrane also demonstrated enhanced anti-bacterial properties, achieving 98.63 and 97.30% inhibition against Staphylococcus aureus and Escherichia coli, respectively. Furthermore, the dynamic fouling experiment showed a 12% higher water flux decrease for the TA/Fe3+-TA/DETA-Ag/PVP CTA membrane compared to the nascent CTA membrane, which proved its excellent antifouling performance. This work provides a feasible strategy to heighten the antifouling property of the CTA FO membrane.


Asunto(s)
Incrustaciones Biológicas , Membranas Artificiales , Ósmosis , Staphylococcus aureus , Incrustaciones Biológicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Taninos/química , Fenoles/química , Antibacterianos/farmacología , Antibacterianos/química , Purificación del Agua/métodos
12.
Environ Geochem Health ; 46(8): 298, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980518

RESUMEN

Grass carp intestinal waste-mediated biosynthesized nanosilver (AgNPs) was valorized using guaran and zeolite matrices, resulting in AgNPs-guaran, AgNPs-zeolite, and AgNPs-guaran -zeolite composites. The valorized products were examined using Environmental Scanning Electron Microscopy, Energy Dispersive X-ray analysis and X-ray Diffraction analysis to confirm uniform dispersion and entrapment of AgNPs within the matrixes. These valorized products were evaluated for their efficacy in detoxifying the ubiquitous and toxic hexavalent chromium (Cr6+) in aquatic environments, with Anabas testudineus exposed to 2 mg l-1 of Cr6+ for 60 days. Remarkable reduction of Cr6+ concentration to 0.86 ± 0.007 mg l-1 was achieved with AgNPs-guaran-zeolite composite, indicating successful reclamation of contaminated water and food safety assurance. Consistency in results was further corroborated by minimal stress-related alterations in fish physiological parameters and integrated biomarker response within the experimental group treated with the AgNPs-guaran-zeolite composite. Despite observed chromium accumulation in fish tissues, evidence of physiological stability was apparent, potentially attributable to trivalent chromium accumulation, serving as an essential nutrient for the fish. Additionally, the challenge study involving Anabas testudineus exposed to Aeromonas hydrophila exhibited the lowest cumulative mortality (11.11%) and highest survival rate (87.5%) within the same experimental group. The current study presents a novel approach encompassing the valorization of AgNPs for Cr6+ detoxification under neutral to alkaline pH conditions, offering a comprehensive framework for environmental remediation.


Asunto(s)
Biomarcadores , Cromo , Nanopartículas del Metal , Plata , Contaminantes Químicos del Agua , Zeolitas , Animales , Cromo/química , Zeolitas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Plata/química , Plata/toxicidad , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Hidrogeles/química , Bioacumulación , Inactivación Metabólica , Galactanos , Mananos , Gomas de Plantas
13.
Toxicol Mech Methods ; : 1-10, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38736318

RESUMEN

This study investigated the mechanism of silver nanoparticle (AgNP) cytotoxicity from a mitochondrial perspective. The effect of AgNP on manganese superoxide dismutase (MnSOD), a mitochondrial antioxidant enzyme, against oxidative stress has not been studied in detail. We demonstrated that AgNP decreased MnSOD mRNA level, protein expression, and activity in human Chang liver cells in a time-dependent manner. AgNP induced the production of mitochondrial reactive oxygen species (mtROS), particularly superoxide anion. AgNP was found to increase mitochondrial calcium level and disrupt mitochondrial function, leading to reduced ATP level, succinate dehydrogenase activity, and mitochondrial permeability. AgNP induced cytochrome c release from the mitochondria into the cytoplasm, attenuated the expression of the anti-apoptotic proteins phospho Bcl-2 and Mcl-1, and induced the expression of the pro-apoptotic proteins Bim and Bax. In addition, c-Jun N-terminal kinase (JNK) phosphorylation was significantly increased by AgNP. Treatment with elamipretide (a mitochondria-targeted antioxidant) and SP600125 (a JNK inhibitor) showed the involvement of MnSOD and JNK in these processes. These results indicated that AgNP damaged human Chang liver cells by destroying mitochondrial function through the accumulation of mtROS.

14.
BMC Oral Health ; 24(1): 146, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297300

RESUMEN

BACKGROUND: Chitosan is known to inhibit the growth of many bacteria and fungi. Tissue conditioners are commonly used to prevent bone destruction under dentures. However, over time, these materials can become a suitable substrate for microbial growth. One approach to improving dental materials is the use of nanoparticles. This study examined the antifungal properties of chitosan and green technique-synthesized silver nanoparticles in combination with tissue conditioners. METHODS: Tissue conditioner materials were mixed with chitosan and silver nanoparticles at concentrations of 0.097%, 0.19%, and 0.37%, along with 1.25 ppm Nystatin, and their antimicrobial properties against Candida albicans were investigated. The growth rate was measured after 24 h of incubation at 37 °C. Non-parametric tests, such as the Kruskal-Wallis H test and Mann-Whitney U test with Bonferroni correction, were used for data analysis after verifying that the groups did not have a normal distribution. RESULTS: Compared with the control and Nystatin groups, the Chitosan-silver groups showed a significant decrease in the number of CFUs of Candida albicans. CONCLUSIONS: The combination of chitosan and silver nanoparticles with tissue conditioner materials is a promising alternative for preventing and treating denture stomatitis. These findings suggest that using very small amounts of nanoparticles in dental materials could effectively prevent microbial growth, which could improve the longevity and efficacy of dental prosthetics and materials.


Asunto(s)
Antiinfecciosos , Quitosano , Nanopartículas del Metal , Estomatitis Subprotética , Humanos , Nistatina/farmacología , Nistatina/uso terapéutico , Quitosano/farmacología , Quitosano/uso terapéutico , Plata/farmacología , Plata/uso terapéutico , Estomatitis Subprotética/tratamiento farmacológico , Nanopartículas del Metal/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida albicans , Materiales Dentales
15.
Indian J Microbiol ; 64(1): 213-224, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38468735

RESUMEN

(NPs) can be produced by various methods such as physical and chemical processes. However, environmentally friendly ways are increasingly requested. In this research, (Ag-NPs) were produced by Fusarium oxysporum, and its antifungal effect on Aspergillus and Fusarium was investigated. Nanoparticles were produced by silver nitrate salt and Fusarium oxysporum native to Isfahan city. In order to optimize the synthesis conditions, optimization of some factors such as volume, concentration, time, temperature, and pH of the extract was performed. The structural and physical properties of NPs were determined by spectrophotometer, XRD, FTIR FESEM, SEM, and TEM microscopy. For the study of the inhibitory effect of NPs on Fusarium and Aspergillus growth, the fungi were cultured in media containing various concentrations of NPs from 50 to 1500 ppm. Then, the colony diameter was measured for over 10 days and the growth inhibition percentage was estimated. For statistical analysis, the 600 Mann-Whitney tests have been applied.The NPs were produced after mixing the powdered fungal mass and silver nitrate salt in optimum conditions which were 2 mM of salt, triple fungal mass volume proportion relative to the salt, pH of 9, and temperature of 28 °C. The existence of a peak at 420 nm in FTIR was due to nanoparticle production. Based on the XRD, the synthesized NPs had suitable properties similar to the standard NPs reported in the studies. Images from TEM, SEM, and FESEM microscopes displayed uniform NPs in variable sizes between 25 and 100 nm. According to the results, the maximum growth inhibition percentage of Ag-NPs on Fusarium was approximately 60% at 1500 ppm, and 88% on Aspergillus at 800 ppm. Biosynthesized Ag-NPs with Fusarium oxysporum have desirable structural traits and can inhibit the growth of Fusarium and Aspergillus at significant levels.

16.
Chemistry ; 29(39): e202300829, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37132089

RESUMEN

Thin layer chromatography (TLC) is widely used to confirm the formation of the target compound in chemical synthesis. The key issue in TLC is spot identification as it primarily relies on retention factors. Coupling of TLC with surface-enhanced Raman spectroscopy (SERS), which gives direct molecular information, is an appropriate choice, to overcome this challenge. However, interference from the stationary phase and impurities on the nanoparticles added for SERS measurements significantly degrades TLC-SERS efficiency. It was found that freezing effectively eliminates such interferences and dramatically improves the performance of TLC-SERS. In this study, TLC-freeze SERS is applied to the monitoring of four chemically important reactions. The proposed method can identify the product and side-products of similar structures, detect compounds with high sensitivity, and provide information of quantities that allows the reliable determination of the reaction time based on kinetic analysis.

17.
Nanotechnology ; 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38081068

RESUMEN

In this study, we demonstrate a facile, durable, and inexpensive technique of producing silver nanoparticles-decorated multi-walled carbon nanotubes (MWCNT/AgNP) on the easy-to-use screen-printed carbon electrodes (SPCE) for non-enzymatic detection of uric acid (UA) in an electrochemical sensor. The developed sensors show great durability for three months in storage, and high specificity performance for preclinical study using spiked UA in a synthetic urine sample. A simple route for this hybrid nanocomposite was proposed through an oxidation-reduction with reflux (ORR) process. A significant increase in the electroactive surface area of SPCE was achieved by modifying it with MWCNT/AgNP. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and X-ray diffraction (XRD) analysis confirmed this synthesis. The nanocomposite nanostructure electrodes achieved an outstanding UA detection with a sensitivity of 0.1021 µA/µM and a wide dynamic range of 10-1000 µM. In PBS, the measurements achieved a detection limit of 84.04 nM while in pure synthetic urine; it was 6.074 µM. The constructed sensor exhibits excellent stability and durability for several months, and great specificity against interfering compounds, including dopamine (DA), urea, and glucose. Overall, the present outcomes denote the potential of MWCNT/AgNP-decorated SPCE for early uric acid diagnostics tools in health monitoring.

18.
Nanotechnology ; 35(6)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37931313

RESUMEN

Silver nanoparticles on a glass substrate are experimentally investigated by aperture scanning near-field optical microscopy (a-SNOM). To understand the experimental results, finite-element-method simulations are performed building a theoretical model of the a-SNOM geometry. We systematically vary parameters like aperture size, aluminum-coating thickness, tip cone angle, and tip-surface distance and discuss their influence on the near-field enhancement. All these investigations are performed comparatively for constant-height and constant-gap scanning modes. In the end, we establish a reliable and stable optical model for simulating a-SNOM measurements, which is capable of reproducing trends observed in experimental data.

19.
J Fluoresc ; 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37439920

RESUMEN

Colorectal cancer (CRC) is a leading cause of morbidity and death worldwide. As current cancer drugs are ineffective, new solutions are being sought in other fields, including nanoscience. Similarly, silver nanoparticles play an important role in the pharmaceutical industry as they act as anti-cancer agents with less harmful effects and are usually 1 to 100 nm in size. Selenic acid (SA) and pyruvic acid (PA) are involved in various metabolic pathways in cancer. For this reason, we decided to detect their influence on colorectal cancer using silver-based (Ag) nanocarriers. DLS, Zetasizer, SEM and UV-Vis analyses were used to characterize AgSA and AgPA. A UV spectrophotometer was used to analyze the release of the NPs. MTT analyses were used to measure the viability of HCT116 and HUVEC cells, and IC50 values were calculated using GraphPad Prism. The indicated dosage and particle size of AgSA NPs proved to be suitable for cytotoxicity. Moreover, injection of these nanoparticles into non-cancer cells proved safe due to their minimal toxicity. In contrast, the AgPA NPs have no cytotoxicity and induce proliferation of HCT116 cells. Finally, only the synthesised AgSA nanoparticles could be used for advanced cancer therapy, which is both inexpensive and has minimal side effects.

20.
Environ Res ; 235: 116648, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37451582

RESUMEN

The current study investigates the potential utilization of poultry intestines for the synthesis of stable silver nanoparticles (AgNPs) and their impact on fish physiology. The AgNPs were synthesized and characterized using various analytical techniques. The toxicity of AgNPs on Anabas testudineus was evaluated, determining a 96-h LC50 value of 25.46 mg l-1. Subsequently, fish were exposed to concentrations corresponding to 1/10th, 1/25th, 1/50th, and 1/100th of the estimated LC50 for a duration of 60 days in a sub-acute study. A comprehensive range of biomarkers, including haematological, serum, oxidative stress, and metabolizing markers, were analyzed to assess the physiological responses of the fish. Additionally, histopathological examinations were conducted, and the accumulation of silver in biomarker organs was measured. The results indicate that silver tends to bioaccumulate in all biomarker organs in a dose- and time-dependent manner, except for the muscle tissue, where accumulation initially increased and subsequently decreased, demonstrating the fish's inherent ability for natural attenuation. Analysis of physiological data and integrated biomarker responses reveal that concentrations of 1/10th, 1/25th, and 1/50th of the LC50 can induce stress in the fish, while exposure to 1/100th of the LC50 shows minimal to no stress response. Overall, this study provides valuable insights into the toxicity and physiological responses of fish exposed to poultry waste biosynthesized AgNPs, offering potential applications in aquaculture while harnessing their unique features.


Asunto(s)
Nanopartículas del Metal , Animales , Nanopartículas del Metal/toxicidad , Plata/toxicidad , Aves de Corral , Peces , Acuicultura , Biomarcadores
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