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International Journal of Molecular... Sep 2023A facile method was developed for preparing size-controlled silver nanoparticles supported by pyrolytic carbon from microcrystalline cellulose (MCC). The pyrolysis of...
A facile method was developed for preparing size-controlled silver nanoparticles supported by pyrolytic carbon from microcrystalline cellulose (MCC). The pyrolysis of cellulose-AgNO mixture caused the oxidation of cellulose, resulting in carboxyl groups to which silver ions can bind firmly and act as nuclei for the deposition of silver nanoparticles. The structure and properties of the obtained nanocomposite were characterized by using a scanning electron microscope (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD). The results suggest that silver nanoparticles were integrated successfully and dispersed uniformly in the pyrolytic carbon matrix. The average particle size varied between 20 nm and 100 nm in correlation to the dose of silver nitrate and temperature of pyrolysis. The products showed high electric conductivity and strong antimicrobial activity against ().
Topics: Metal Nanoparticles; Escherichia coli; Spectroscopy, Fourier Transform Infrared; Anti-Bacterial Agents; Silver; Cellulose; X-Ray Diffraction
PubMed: 37833880
DOI: 10.3390/ijms241914431 -
Cureus Nov 2023Silver nanoparticles (AgNPs) are considered to be a very significant and intriguing type within the category of metallic nanoparticles, particularly in the context of...
AIM
Silver nanoparticles (AgNPs) are considered to be a very significant and intriguing type within the category of metallic nanoparticles, particularly in the context of their involvement in biological applications. The objective of this research is to use the green synthesis method in order to synthesize AgNPs by using the leaf extract of . Furthermore, the study aims to evaluate the antioxidant and anti-inflammatory properties of these nanoparticles.
MATERIALS AND METHODS
Fresh and healthy specimens of were gathered from Palk Bay, Tamil Nadu, India, and afterward subjected to a thorough washing process using tap water. The cleaned materials were air-dried and then fragmented into small bits and finely ground. The ethanolic extract of seagrass was then combined with a solution containing 1 millimolar (mM) silver nitrate (AgNo). The decrease of silver ions in the solution was frequently measured using a UV-visible spectrophotometer. Synthesized AgNPs were investigated for antioxidants by DPPH (2,2-diphenyl-1-picrylhydrazyl) assay and anti-inflammatory activity was measured by protein-denaturation assay.
RESULTS
The use of leaf extract in the green synthesis of AgNPs, in the presence of 1 mM AgNO, led to a noticeable alteration in the colour of the mixture, transitioning from a pale hue to a brown shade. This change in colour serves as evidence of the reduction of AgNo ions to silver ions, thereby facilitating the creation of AgNPs. The duration of the bio-reduction process of silver ions in the reaction mixture was observed to be two hours. The antioxidant and anti-inflammatory activity showed promising activity for AgNPs.
CONCLUSION
This study concluded that had antioxidant capabilities, and AgNPs derived from have potential use in pharmaceuticals and medication administration.
PubMed: 38143665
DOI: 10.7759/cureus.49316 -
Science Progress 2023The tobacco cutworm () is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for...
The tobacco cutworm () is a widespread pest that inflicts severe damage on various crops, including cotton, tobacco, and vegetables, with a particular preference for solanaceous plants. Traditional control methods often rely heavily on synthetic insecticides, leading to adverse effects on the environment, human health, and the development of insecticide resistance. In light of these challenges, this study explores the potential of nanotechnology as an innovative and sustainable approach to combat this notorious pest. Bioassays were conducted using laboratory-reared 3rd instar larvae. Eight different plant extracts coated with zinc oxide and silver nitrate nanoparticles were tested, with concentrations in both distilled water and ethanol at 3, 5, and 7 ml. Data were collected at 24, 48, and 72-h intervals. The results revealed that the highest larval mortality, reaching 98%, was observed in the group treated with silver nitrate nanoparticles derived from . In comparison, the group treated with zinc oxide nanoparticles dissolved in ethanol exhibited a larval mortality rate of 90%. Ethanol is a polar solvent that is widely used in the synthesis of nanocomposites. It is capable of forming strong hydrogen bonds with oxygen atoms, making it a good dispersant for zinc oxide nanoparticles. Additionally, ethanol has a low boiling point and a non-toxic nature, which makes it a safe and effective option for the dispersion of nanoparticles. Notably, the study concluded that silver nanoparticles combined with ethanol exhibited prolonged and more potent toxic effects against when compared to zinc oxide nanoparticles. Overall, this research underscores the potential of nanotechnology as a valuable component of Integrated Pest Management (IPM) strategies. By integrating nanotechnology into pest management practices, we can promote sustainable and environmentally friendly approaches that benefit both farmers and the ecosystem.
Topics: Animals; Ecosystem; Ethanol; Larva; Metal Nanoparticles; Nitrates; Plant Extracts; Silver; Silver Nitrate; Spodoptera; Zinc Oxide; Pest Control
PubMed: 38113117
DOI: 10.1177/00368504231219171 -
Treating hypersensitivity in older adults with silver diamine fluoride: A randomised clinical trial.Journal of Dentistry Sep 2023This study aimed to evaluate the desensitizing effect of topically applied 38% silver diamine fluoride (SDF) solution on the exposed root surface of hypersensitive teeth... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
This study aimed to evaluate the desensitizing effect of topically applied 38% silver diamine fluoride (SDF) solution on the exposed root surface of hypersensitive teeth in older adults.
METHOD
This double-blind randomised clinical trial recruited healthy older adults with dentine hypersensitivity. A trained examiner tested the most hypersensitive tooth root surface with a blast of compressed cold air from a three-in-one syringe. The participants gave a sensitivity score (SS) in visual analogue scale from 0 (no pain) to 10 (agonizing) at the baseline visit. Then, they received 38% SDF or 5% potassium nitrate solution (control) as intervention on the root surface. After the intervention, they received a compressed cold air test and reported the SS again. The compressed cold air test followed by intervention was repeated at 4- and 8-week follow ups. The primary outcome was the reduction in SS at 8-week follow-up with reference to the SS at baseline before intervention. Shapiro-Wilk and Mann-Whitney U tests were performed for data analysis following a normality test of SS.
RESULTS
This trial recruited 148 participants, and 139 (94%) participants completed the trial. The median percentage reductions in SS in the SDF and potassium nitrate groups were 60% and 50%, respectively (p < 0.001).
CONCLUSION
According to the results, 38% SDF solution reduced hypersensitivity on the exposed root surface of older adults. In addition, 38% SDF was more effective than 5% potassium nitrate solution to reduce hypersensitivity on the exposed root surface of older adults.
CLINICAL SIGNIFICANCE
Dentin hypersensitivity is common amongst older adults and negatively affects their quality of life. To date, there is no gold standard professionally applied desensitizing therapy in treating hypersensitivity. Evidence from this clinical trial could aid clinical practice and improve oral health in older adults.
TRIAL REGISTRATION
This study was registered at ClinicalTrials.gov (NCT05392868).
Topics: Humans; Aged; Sodium Fluoride; Quality of Life; Treatment Outcome; Dentin Sensitivity; Silver Compounds; Double-Blind Method; Fluorides; Dentin Desensitizing Agents
PubMed: 37454789
DOI: 10.1016/j.jdent.2023.104616 -
Gels (Basel, Switzerland) Nov 2023Herein, the problem concerning the poorer mechanical properties of gels based on low molecular weight gelators (LMWGs)-L-cysteine and silver nitrate-was solved by the...
Herein, the problem concerning the poorer mechanical properties of gels based on low molecular weight gelators (LMWGs)-L-cysteine and silver nitrate-was solved by the addition of various polymers-polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP) and polyethylene glycol (PEG)-to the initial cysteine-silver sol (CSS). The physicochemical methods of analysis-viscosimetry, UV spectroscopy, DLS, and SEM-identified that cysteine-silver hydrogels (CSG) based on PVA possess the best rheological properties and porous microstructure (the average pore size is 2-10 µm) compared to gels without the polymer or with PVP or PEG. Such gels are able to form cysteine-silver cryogels (CSC) and then porous cysteine-silver films (CSF) with an average pore size of 10-20 µm and good mechanical, swelling, and adhesion to skin characteristics as long as the structure of CSS particles remains stable. In vitro experiments have shown that hydrogels are non-toxic to normal human fibroblast cells. The obtained materials could potentially be applied to regenerative medicine.
PubMed: 38131910
DOI: 10.3390/gels9120924 -
Biomedicines Aug 2023Antimicrobial resistance (AMR) has become a topic of great concern in recent years, with much effort being committed to developing alternative treatments for resistant...
Antimicrobial resistance (AMR) has become a topic of great concern in recent years, with much effort being committed to developing alternative treatments for resistant bacterial pathogens. Drug combinational therapies have been a major area of research for several years, with modern iterations using combining well-established antibiotics and other antimicrobials with the aim of discovering complementary mechanisms. Previously, we characterised four GRAS antimicrobials that can withstand thermal polymer extrusion processes for novel medical device-based and therapeutic applications. In the present study, four antimicrobial bioactive-silver nitrate, nisin, chitosan and zinc oxide-were assessed for their potential combined use as an alternative synergistic treatment for AMR bacteria via a broth microdilution assay based on a checkerboard format. The bioactives were tested in arrangements of two-, three- and four-drug combinations, and their interactions were determined and expressed in terms of a synergy score. Results have revealed interesting interactions based on treatments against recognised test bacterial strains that cause human and animal infections, namely , and . Silver nitrate was seen to greatly enhance the efficacy of its paired treatment. Combinations with nisin, which is a lantibiotic, exhibited the most interesting results, as nisin has no effect against Gram-negative bacteria when used alone; however, it demonstrated antimicrobial effects when combined with silver nitrate or chitosan. This study constitutes the first study to both report on practical three- and four-drug combinational assays and utilise these methods for the assessment of established and emerging antimicrobials. The novel methods and results presented in this study show the potential to explore previously unknown drug combination compatibility measures in an ease-of-use- and high-throughput-based format, which can greatly help future research that aims to identify appropriate alternative treatments for AMR, including the screening of potential new bioactives biorefined from various sources.
PubMed: 37626713
DOI: 10.3390/biomedicines11082216 -
Archives of Toxicology Jul 2023Silver (Ag; massive, powder and nanoform) and Ag compounds are used in industrial, medical and consumer applications, with potential for human exposure. Uncertainties...
Silver (Ag; massive, powder and nanoform) and Ag compounds are used in industrial, medical and consumer applications, with potential for human exposure. Uncertainties exist about their comparative mammalian toxicokinetic ('TK') profiles, including their relative oral route bioavailability, especially for Ag massive and powder forms. This knowledge gap impedes concluding on the grouping of Ag and Ag compounds for hazard assessment purposes. Therefore, an in vivo TK study was performed in a rat model. Sprague-Dawley rats were exposed via oral gavage for up to 28 days to silver acetate (AgAc; 5, 55, 175 mg/kg(bw)/d), silver nitrate (AgNO; 5, 55, 125 mg/kg(bw)/d), nanosilver (AgNP; 15 nm diameter; 3.6, 36, 360 mg/kg(bw)/d) or silver powder (AgMP; 0.35 µm diameter; 36, 180, 1000 mg/kg(bw)/d). Total Ag concentrations were determined in blood and tissues to provide data on comparative systemic exposure to Ag and differentials in achieved tissue Ag levels. AgAc and AgNO were the most bioavailable forms with comparable and linear TK profiles (achieved systemic exposures and tissue concentrations). AgMP administration led to systemic exposures of about an order of magnitude less, with tissue Ag concentrations 2-3 orders of magnitude lower and demonstrating non-linear kinetics. The apparent oral bioavailability of AgNP was intermediate between AgAc/AgNO and AgMP. For all test items, highest tissue Ag concentrations were in the gastrointestinal tract and reticuloendothelial organs, whereas brain and testis were minor sites of distribution. It was concluded that the oral bioavailability of AgMP was very limited. These findings provide hazard assessment context for various Ag test items and support the prediction that Ag in massive and powder forms exhibit low toxicity potential.
Topics: Male; Rats; Humans; Animals; Rats, Sprague-Dawley; Powders; Toxicokinetics; Silver Compounds; Silver Nitrate; Administration, Oral; Metal Nanoparticles; Mammals
PubMed: 37195448
DOI: 10.1007/s00204-023-03511-6 -
Heliyon Sep 2023The objective of this study was to determine the optimal dose of silver nitrate (AgNO) for plant growth and to increase the main bioactive compounds in cultivated in a...
The objective of this study was to determine the optimal dose of silver nitrate (AgNO) for plant growth and to increase the main bioactive compounds in cultivated in a hydroponic system. The application of soaked diniconazole (120 μmol mol) to all plants at 7 days after transplanting (DAT) for dwarfing plant height, optimizing cultivation space in the plant factory. Subsequently, plants were soaked with 50, 100, 200, and 400 μmol mol AgNO for 10 min at 25 DAT and harvested at 39 DAT. The results indicated that 200 and 400 μmol mol treatments tended to severely decrease plant growth parameters compared to treatments with lower concentrations. The net photosynthetic rate was significantly reduced by the 200 and 400 μmol mol treatments compared to treatments with other concentrations. The 400 μmol mol treatment led to the lowest concentrations of chlorophyll , chlorophyll /b, total carotenoid, chlorophyll , and the total chlorophyll. However, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was considerably increased in 50, 100, 200, and 400 μmol mol compared to that of the control plants. A higher rosmarinic acid (RA) concentration in the whole plant was noticed with the 400 μmol mol treatment compared with that of the untreated plants. The 100 μmol mol treatment exhibited the highest concentration and content of tilianin in the whole plant. Concentration of acacetin 1 significantly increased in the whole plant with 100 and 200 μmol mol treatments compared with that of the untreated plants. Concentrations of acacetin 2 and 3 in the whole plant were the highest with 100 and 200 μmol mol treatments, respectively. The results demonstrated that 100 μmol mol treatments can be used to increase bioactive compounds without severely limiting the plant growth and reducing chlorophyll concentrations of . Implementing this optimal dose can enable growers and researchers to cultivate more efficiently, enhancing bioactive compound content and overall plant performance, thus harnessing the potential health benefits of this valuable plant species.
PubMed: 37810151
DOI: 10.1016/j.heliyon.2023.e20205 -
Current Medical Mycology Sep 2023Regarding the wide-spectrum antimicrobial effects of curcumin and silver, this study aimed to evaluate the antifungal activity of green-synthesized curcumin-coated...
BACKGROUND AND PURPOSE
Regarding the wide-spectrum antimicrobial effects of curcumin and silver, this study aimed to evaluate the antifungal activity of green-synthesized curcumin-coated silver nanoparticles (Cur-Ag NPs) against a set of and species.
MATERIALS AND METHODS
Cur-Ag NPs were synthesized by mixing 200 µL of curcumin solution (40 mM) and 15 mL of deionized water. The mixture was stirred for 3-5 min, followed by the addition of 2.5 mL of silver nitrate solution (2.5 mM). The resulting solution was incubated for 3 days. Antifungal susceptibility of 30 fungal isolates of and to fluconazole and itraconazole, as well as the activity of Cur-Ag NPs against the isolates, were determined, both alone and in combination, using broth microdilution according to the Clinical and Laboratory Standards Institute guidelines.
RESULTS
Cur-Ag NPs demonstrated promising antifungal activity, particularly against species. The geometric mean value of the minimum inhibitory concentration of Cur-Ag NPs was significantly lower than that of fluconazole for all the studied fungi. Similarly, it was lower than those of itraconazole in and . The minimum fungicidal concentrations of Cur-Ag NPs were markedly better than those of fluconazole but still inferior to those of itraconazole.
CONCLUSION
Cur-Ag NPs demonstrated indisputable antifungal activity and great potential that can be harnessed to combat fungal infections, particularly those caused by azole-resistant strains of and .
PubMed: 38361962
DOI: 10.22034/cmm.2023.345125.1456 -
Journal, Genetic Engineering &... Nov 2023At the present time, there is a persistent need to get rid of environmental contaminants by eco-friendly, sustainable, and economical technologies. Uncontrolled disposal...
OBJECTIVES
At the present time, there is a persistent need to get rid of environmental contaminants by eco-friendly, sustainable, and economical technologies. Uncontrolled disposal practices of domestic and industrial solid and liquid wastes led to water pollution which has negative impacts on public health, environment, and socio-economic development. Several water-borne diseases are spreading man to man by microorganisms such as pathogenic bacteria. For the protection of water bodies, all wastewater from various sources should be managed and remediated properly. Myco-remediation is a form of bioremediation in which fungi are used to get rid of contaminants. Fungi are attractive agents for the biosynthesis of nanoparticles especially silver nanoparticles (AgNPs) which are considered one of the most widely utilized nanoparticles because of their unique characteristics such as antibacterial, antiviral, antifungal, and anti-inflammatory properties.
METHODS
This study uses silver nitrate and supernatants of four marine fungi; Penicillium simplicissimum, Aspergillus terreus, Aspergillus japonicus, and Aspergillus oryzae for extracellular biosynthesis of silver nanoparticles and to evaluate its activity against different pathogenic microorganisms. These nanoparticles may subsequently be applied for the treatment or nano-bioremediation of microbial contaminants in water bodies and improve water quality.
RESULTS
Silver nanoparticles were synthesized and the results revealed that spherical and well-dispersed nanoparticles of different sizes were formed with sizes ranging between 3.8 and 23 nm. Characterization results approved the existence of stable nanocrystalline elemental silver. Antibacterial activity results revealed that AgNPs can be used as a powerful antimicrobial agent for several pathogenic bacteria, yeast, and fungi. Among the biosynthesized NPs mediated by the four marine fungi, AgNPs mediated by A. japonicus (5 mM) had the highest antibacterial activity, while AgNPs mediated by Penicillium simplicissmum (8 mM) had the highest antifungal activity.
CONCLUSION
Marine fungi can biosynthesize stable AgNPs that exhibit potent antimicrobial activity against a variety of pathogens.
PubMed: 37985623
DOI: 10.1186/s43141-023-00572-z