Nanosilver Solution Research Articles

Effects of silver nanoparticle on Morinda officinalis How

Nanosilver is a form of silver metal particles, extremely small nano-sized particles, about 1 to 100 nm. Nanosilver solution can be used to treat the soil before sowing or planting trees to control pathogenic microbes and improve plant growth and development. Nevertheless, the study on the effects of silver nanoparticles remains limited. Therefore, the aim of the current study was to examine the effects of nanosilver concentration on the growth and development of Morinda officinalis How grown in Ba Che district, Quang Ninh province. The silver nanoparticle solution (2 to 10 ppm) mixed with the extract of sour star fruit was sprayed on the seedlings of M. officinalis How and their growth and development were measured. The results showed that the use of nano-silver solution affected the growth and development of Morinda officinalis How. The study successfully prepared a 500 ppm nanosilver solution by a chemical reduction method with reducing agent extracted from the sour star fruit. It has the dual effect of both promoting growth and development as well as producing the best tuber quality for Morinda officinalis How grown in Ba Che, Quang Ninh at 6 ppm.

Nano silver composite hydroxyethyl methacrylate/vinylpyrrolidone hydrogel: Tissue adhesives with antibacterial properties

Bacterial wound infections are prevalent in daily life. However, conventional tissue adhesives lack antimicrobial properties. In this study, a redox method was employed to prepare a nano-silver solution with tannic acid as a dispersant. Subsequently, the nano-silver solution was combined with the precursor solution of the hydroxyethyl methacrylate/vinylpyrrolidone (HEMA/NVP) hydrogel. Finally, it was put under ultraviolet light to produce the hydrogel. The hydrogel exhibits remarkable extendibility (1223 %), an elastic modulus compatible with human skin tissue (3.7 ± 0.5 kPa), the strong adhesion to porcine skin tissue (24.67 ± 1.15 kPa) markedly exceeds that achieved by clinically utilized fibrin glue, low swelling ratio (75 ± 1.55 %), and demonstrates good in vitro antimicrobial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Furthermore, it displays excellent biocompatibility with fibroblast cells (NIH/3T3) with cell viability above 80 %, favorable blood compatibility with goat blood, and moderate coagulation ability. It provides more possibilities for clinical wound repair.

Comparative Evaluation of the Antibacterial Efficacy of Aloe Vera, 3% Nano Silver Solution, and 2% Chlorhexidine Gluconate on Enterococcus faecalis: An In Vitro Study

Comparative Evaluation of the Antibacterial Efficacy of Aloe Vera, 3% Nano Silver Solution, and 2% Chlorhexidine Gluconate on Enterococcus faecalis: An In Vitro Study

Comparative Analysis of Performance of Water-Based Coatings Prepared by Two Kinds of Anti-Bacterial Microcapsules and Nano-Silver Solution on the Surface of Andoung Wood

A nano-silver solution, urea-formaldehyde resin-coated nano-silver solution microcapsules (AgNPS@UF), and melamine-formaldehyde resin-coated chitosan-modified nano-silver solution microcapsules (CS-AgNPS@MF) were added into the coatings at different contents for comparative tests to explore an anti-bacterial agent with the best anti-bacterial properties in the water-based coatings on Andoung wood (Monopetalanthus spp.). As the content of anti-bacterial agents increased, AgNPS@UF had the best anti-bacterial property towards Staphylococcus aureus and Escherichia coli, with anti-bacterial rates of 79.0% and 82.1%, respectively. The optical and mechanical properties of the coating quickly worsened as the content of anti-bacterial agents increased. The anti-bacterial coatings with AgNPS@UF have the minimum chromatic aberration change of 6.5. The anti-bacterial coating with 5% content of AgNPS@UF decreased the aging rate. This coating had good optical properties, and its liquid-resistant level is 2. When the 5% content of AgNPS@UF was added, after high-temperature accelerated aging and ultraviolet (UV) aging, the anti-bacterial rates of the coating with AgNPS@UF decreased toward Escherichia coli from 82.1% to 62.2% and decreased toward Staphylococcus aureus from 79.3% to 61.1%, respectively. This shows that the coating had a long-lasting anti-bacterial property. The anti-bacterial property of the coating after high-temperature accelerated aging was superior to that after the UV aging. The incorporation of AgNPS@UF in water-based coatings protects people from the risks of Escherichia coli and Staphylococcus aureus more effectively with long-lasting property. The research results provide a reference for the preparation of anti-bacterial water-based coatings on the surface of the Andoung wood.

Preparation of Chitosan-Modified Nano-Silver Solution Microcapsules and Their Effects on Antibacterial Properties of Waterborne Coatings

In this paper, a chitosan-modified nano-silver solution was used as the core material of an antibacterial agent, and melamine formaldehyde resin was coated onto the core material to obtain the antibacterial microcapsules. The core/wall ratio, the stirring rate, the mass ratio of chitosan to silver ions, and the concentration of the emulsifier were used to carry out four-factor and three-level orthogonal experiments to explore the most significant factors affecting the coverage rate and output of microcapsules and the best preparation technology. The results showed that the concentration of the emulsifier was the most important factor affecting the preparation of microcapsules. The higher the concentration of the emulsifier, the better the dispersed morphology of microcapsules, and the higher the coverage rate, up to 44.0%. The antibacterial coating was prepared by mixing microcapsules with a waterborne primer at a content of 4.0%. Its optical properties, mechanical properties, and antibacterial properties were analyzed. By increasing the concentration of the emulsifier, the gloss of the coating showed a trend of first increasing and then decreasing. When the emulsifier concentration was 2.0%, the gloss of the Andoung wood surface coating reached the maximum value of 21.23%. The influence of emulsifier concentration on the color difference of coating had no obvious law, and it was negatively related to the light transmittance. In terms of mechanical properties, the concentration of the emulsifier is directly proportional to the hardness and impact resistance of the coating, with the maximum reaching 31 kg·cm, and is negatively related to adhesion and roughness. In terms of antibacterial properties, the higher the concentration of the emulsifier, the better the antibacterial properties of the coating. When the concentration of the emulsifier was 4.0%, the antibacterial rates of coating which coated the glass substrate were 71.3% and 80.0% for Escherichia coli and Staphylococcus aureus, respectively. The antibacterial rates of the Andoung wood surface coating reached the maximum, which were 68.4% and 73.2%, respectively, and the antibacterial performance was excellent. In this study, an efficient antibacterial microcapsule for waterborne coatings was prepared, which provided the reference value for the application of antibacterial microcapsules in waterborne coatings.

Preparation of Antibacterial Nanosilver Solution Microcapsules and Their Impact on the Performance of Andoung Wood Surface Coating.

In this paper, nanosilver solution was used as an antibacterial agent to prepare antibacterial microcapsules. The mass ratio of the core material to the wall material (Wcore: Wwall), the emulsifier's hydrophilic-lipophilic balance (HLB) value, the mass ratio of ethanol to the emulsifier in solvent (Wcore: Wemulsion), and the rotational speed (r/min) were used to develop the four-factor, three-level orthogonal experiment, which was meant to investigate the most significant factors and the optimum process preparation parameters impacting the coating rate and yield of microcapsules. It was used to make an antibacterial coating that was applied to the surface paint film of a glass substrate and andoung wood, and it was mixed to the water-based primer with a content of 4%. Analyses of the mechanical, optical, and bactericidal characteristics were conducted. The micromorphology of the nanosilver solution microcapsules is influenced by the emulsifier's HLB value. The color difference of the antibacterial coating film decreased with increasing emulsifier HLB value; however, the coating film's gloss remained largely suitable. Additionally, the coating film's transparency and tensile strength both decreased. It had minimal impact on the paint film's surface hardness, but the adhesion and tensile strength showed a noticeable downward trend. The surface of the paint film was rough. Escherichia coli and Staphylococcus aureus were resistant to the antibacterial characteristics of the water-based primer film when it was combined with antibacterial nanosilver solution microcapsules by 80.7% and 74.55%, respectively. The coating film's antibacterial properties were applied to the surface of the andoung wood, which were 75.7% and 71.0%, respectively, and somewhat decreased. In order to successfully inhibit bacteria, the nanosilver solution microcapsules were added to waterborne coatings. This ensures both the outstanding performance of the coating film and the effectiveness of the antibacterial effect. It expands the application prospects of antibacterial microcapsules in coatings.

Treatment of infection and inflammation associated with COVID-19, multi-drug resistant pneumonia and fungal sinusitis by nebulizing a nanosilver solution

Solutions containing Ag0 nanoclusters, Ag+1, and higher oxidation state silver, generated from nanocrystalline silver dressings, were anti-inflammatory against porcine skin inflammation. The dressings have clinically-demonstrated broad-spectrum antimicrobial activity, suggesting application of nanosilver solutions in treating pulmonary infection.Nanosilver solutions were tested for antimicrobial efficacy; against HSV-1 and SARS-CoV-2; and nebulized in rats with acute pneumonia. Patients with pneumonia (ventilated), fungal sinusitis, burns plus COVID-19, and two non-hospitalized patients with COVID-19 received nebulized nanosilver solution.Nanosilver solutions demonstrated pH-dependent antimicrobial efficacy; reduced infection and inflammation without evidence of lung toxicity in the rat model; and inactivated HSV-1 and SARS-CoV-2. Pneumonia patients had rapidly reduced pulmonary symptoms, recovering pre-illness respiratory function. Fungal sinusitis-related inflammation decreased immediately with infection clearance within 21 days. Non-hospitalized patients with COVID-19 experienced rapid symptom remission.Nanosilver solutions, due to anti-inflammatory, antiviral, and antimicrobial activity, may be effective for treating respiratory inflammation and infections caused by viruses and/or microbes.

Evaluation of the Microbiological Effect of Colloidal Nanosilver Solution for Root Canal Treatment.

Background: The goal of endodontic treatment, along with the preparation of the root canal and giving it a shape corresponding to the obturation technique, is the drug treatment of the canal. The aim of this study was to determine the antibacterial effect of a colloidal solution of nanosilver at its various dilutions on root canal microorganism. Materials and methods: A solution of silver nanoparticles at a concentration of 10,000 ppm (1.0%) was diluted in various concentrations (10 solutions from 1% to 0.0025%). Cultures used for research: Str. agalacticae ATCC 3984, E. faecalis ATCC 323, St. aureus ATCC 4785, C. albicans ATCC 10231. After thawing, cultures of microorganisms were introduced into a liquid nutrient medium: cerebral heart broth for bacterial cultures and Sabouraud broth for C. albicans. The cultivation was carried out at a temperature of 37 °C for 24 h. A bacterial suspension for inoculation was prepared from a microbial sediment according to a turbidity standard of 0.5 McFarland in saline. Then, 100 μL of the obtained suspension of microorganisms was inoculated by the “lawn” method using a spatula on the Muller–Hinton medium. Solutions of silver nanoparticles were introduced into wells prepared in agar with a sterile metal punch. Further incubation was carried out for 24 h at 37 °C. Results: colloidal solution of silver nanoparticles at concentrations of 1%, 0.75%, 0.5% inhibited the growth of Str. agalacticae ATCC 3984 with a growth retardation zone of 6–7 mm. The E. faecalis ATCC 29212 strain was sensitive to solutions of silver nanoparticles at concentrations of 1%, 0.75%, 0.5% with a growth inhibition zone of 6–7 mm. Strain St. aureus 4785 demonstrated sensitivity to solutions of silver nanoparticles at concentrations of 1%, 0.75%, 0.5%, 0.1%, 0.05% with a growth retardation zone of 6-8 mm. Conclusion: colloidal solutions of silver nanoparticles have antimicrobial action against gram-positive bacteria (Str.agalacticae ATCC 3984, St. aureus ATCC 4785, E. faecalis ATCC 29212) and yeast-like fungi of the genus Candida (C. albicans ATCC 10231, C. albicans 672 and C. albicans D-225M), but this action is strain-specific and depends on the concentration of the solution.

Preservation of Litchi Fruit with Nanosilver Composite Particles (Ag-NP) and Resistance against Peronophythora litchi.

Litchi (Litchi chinensis Sonn.) is susceptible to infection by Peronophythora litchi post storage, which rapidly decreases the sensory and nutritional quality of the fruit. In this study, the effects of nanosilver (Ag-NP) solution treatment on the shelf life of litchi fruit and the inhibition of P. litchi were examined, and the underlying mechanisms were discussed. For investigations, we used one variety of litchi (‘Feizixiao’), dipping it in different concentrations of Ag-NP solution after harvesting. Meanwhile, we treated P. litchi with different concentrations of Ag-NP solution. According to the data analysis, litchi treated with 400 μg/mL Ag-NPs and stored at 4 °C had the highest health rate and the lowest browning index among all the samples. In the same trend, treatment with 400 μg/mL Ag-NPs produced the best results for anthocyanin content, total soluble solids content, and titratable acidity content. Additionally, according to the results of the inhibition test, 800 μg/mL Ag-NP solution had a 94.97% inhibition rate against P. litchi. Within 2–10 h following exposure to 400 μg/mL Ag-NP solution, the contents of superoxide dismutase, peroxidase, and catalase in P. litchi gradually increased and peaked, followed by a gradual decline. At this time, the integrity of the cell membrane of P. litchi could be broken by Ag-NP solution, and the sporangia showed deformed germ tubes and abnormal shapes. Taken together, these results suggested that Ag-NP treatment inhibited respiration and P. litchi activity, which might attenuate litchi pericarp browning and prolong the shelf life of litchi. Accordingly, Ag-NPs could be used as an effective antistaling agent in litchi fruit and as an ecofriendly fungicide for the post-harvest control of litchi downy blight. This study provides new insights into the application of Ag-NP as an antistaling agent for fruit storage and as an ecofriendly fungicide.

Nanomaterials in Sports Training and Its Biological Safety

Nanomaterials have many special functions. Sports field provides a platform for nanomaterials to show their excellent performance. At the same time, nanomaterials in the body may also have negative effects on cells, lung tissue, liver and kidney tissue, and brain tissue; there are certain biological safety risks. Based on the above background, this article studies the application and biological safety of nanomaterials in sports training. In this article, silver nanoparticles were prepared by improved liquid-phase chemical reduction method and photochemical reduction method. The antibacterial properties of silver nanoparticles with different concentrations and sizes were tested and characterized, and the possible antibacterial mechanism was speculated. Nanosilver refers to the metallic silver element with the particle size to the nanoscale. The acute toxicity test and hemolytic test were carried out on the safety of silver nanoparticles. In the acute toxicity test, when 100 μL nanosilver solution was added, the visceral weight, body weight, and tissue sections of mice were almost not affected; in terms of biochemical indexes, all biochemical indexes returned to normal when the injection volume was 0.1 μL. The results show that nanosilver still has certain influence on biochemical indexes at high dose. How to reduce the influence will be one of the key work in the future. In addition, hemolysis test showed that no hemolysis occurred when nanosilver solution was injected at 2.77 μL. This will lay a foundation for the use of nanosilver sportswear in direct contact with human blood in the future.

0.1% Nano-silver mediates PD-1/PD-L1 pathway and alleviates chronic apical periodontitis in rats.

This study was to investigate whether the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) and T-helper 17 (Th17)/regulatory T (Treg) balance are associated with chronic apical periodontitis (CAP) relived by 0.1% nano-silver. CAP rat models were established by opening the first molars of the right and left mandible and exposing the pulp cavity to the oral cavity. CAP model was verified by cone-beam computed tomography, X-ray digital radiovisiography, and hematoxylin-eosin (H and E) staining. The rats were randomly divided into the sham, Ca(OH)2, and 0.1% nano-silver groups (n = 12 in each group) 2weeks after surgery. The pathological changes in the apical area were detected by H and E staining. PD-1, PD-L1, RORγT, IL-17, and Foxp3 in periapical tissues were detected by qRT-PCR and immunohistochemistry. Th17/Treg and PD-1/PD-L1 were analyzed by flow cytometry. After 7, 14, and 21days of 0.1% nano-silver treatment, inflammatory cells in the apical region were slightly reduced and inflammatory infiltration was relieved compared with the sham group. RORγT, IL-17, PD-1, and PD-L1 decreased and Foxp3 increased after 7, 14, and 21days of 0.1% nano-silver treatment compared with the sham group (p < 0.05); however, there were no significant differences with Ca(OH)2 group (p > 0.05). Flow cytometry revealed that 0.1% nano-silver solution decreased Th17/Treg and PD-1/PD-L1 ratio. 0.1% Nano-silver significantly reduced the inflammation of CAP in rats. PD-1/PD-L1 was included in Th17/Treg balance restored by 0.1% nano-silver.

Effects of various treatment methods on decay resistance and dimensional stability of nano-silver-treated Persian/Shiraz inlay (Khatam)

Four types of Shiraz inlay (Khatam) samples were impregnated with nano-silver solution via spraying (S), a vacuum desiccator (VD), and immersion/dipping (I/D) for 2 h and 24 h techniques. The decay resistance and dimensional stability were evaluated after each treatment. The impregnated specimens were exposed to white-rot fungus for 10 weeks by the agar-plate method, and the weight loss was determined to assess decay. The dimensional stability of samples after 2 and 24 h soaking in water were measured. According to the results, the highest weight loss (13.1%) was observed in the Shesh-Pareh Khatam (SPK)-untreated samples and the lowest weight loss (1.5%) occurred in the Ostokhani Khatam (OK)-VD-treated samples. The highest volumetric shrinkage (39.0%) was observed in the Haft Shamseh Alam-Zar Khatam (HSAZK)-untreated samples after 24 h soaking, and the lowest volumetric shrinkage (3.8%) was noted in the OK-S-treated samples after 2 h soaking. The highest volumetric swelling (64.1%) was observed in the HSAZK-untreated samples after 24 h soaking, and the lowest volumetric swelling (4%) was found in the OK-S-treated samples after 2 h soaking in water. Generally, the highest anti-shrinkage-efficiency (111.0%) and anti-swelling-efficiency (145.4%) after 24 h soaking in water were observed in the OK-S-treated and SPK-VD-treated samples, respectively.

Evaluation of nanosilver solution stability using UV-Vis spectral absorbency analysis and antibacterial activities on Escherichia coli and Staphylococcus aureus

Recently, the use of nanomaterials in industrial and technological applications for various fields is quickly growing. The “green” synthesis of metallic nanoparticles has received increasing attention due to the development of eco-friendly technologies. In our previous research, silver nanoparticles have been successfully prepared in gelatin (Ag/Gelatin sample), Gelatin/Chitosan (Ag/Gelatin/Chitosan sample) and chitosan (Ag/Chitosan sample) suspensions using a chemical reducing agent. For this purpose, biological grade gelatin and chitosan were used as reducing and stabilizing agents without special physical conditions. The most advantage of this work is using a renewable material like gelatin as a reducing factor, which is eco-friendly agent. However, one of the most important issues related to those nanofluids is their stability, and it remains as a big challenge to achieve desired applications in future. Thus, all obtained nanosilver samples were characterized by UV-Vis spectroscopy and evaluated the stability of antibacterial activity on Escherichia coli, Staphylococcus aureus. The absorption spectra results of the samples, which were measured after storage for three months, illustrated that the absorption peaks of the silver nanoparticles in Ag/Gelatin and Ag/Chitosan had shifted slightly from 423 to 425 nm and 435 to 440 nm, respectively. Whereas, the absorption peak for the Ag/Gelatin/Chitosan remained the same at 423 nm. In addition, after storage for three months, Ag/Gelatin/Chitosan sample showed antibacterial activity better than the two remaining samples with the reduction of inhibition zones is insignificant at 21.5 ± 0.25 mm while testing on Escherichia coli and at 15.5 ± 0.25 mm on Staphylococus aureus. The results suggested that silver nanoparticles were prepared in Gelatin/Chitosan composition showing promising stability and antibacterial activity which are beneficial for various/diversed/further applications.

Teaching Research on Using Nano Silver Ion Dressing in Clinical Nursing of Surgically Infected Wounds.

In real life, there are few occasions where nanomaterials are exposed alone, and more often they coexist with other chemical substances. This article mainly studies the teaching of using nano-silver dressings in clinical nursing of surgically infected wounds. In this paper, the convenience sampling method is used to select 60 patients with chronic wounds as the research objects. A 160μg/mL nano-silver solution prepared with 10% fetal bovine serum DMEM culture medium was dropped on the copper net, and TEM was used for detection. The nanosilver dispersed in different dispersions was divided into 4mL EP tubes and incubated at 4°C, 25°C and 37°C for 0, 3, 12, 24, and 48 hours, and the sample at different time points were detected by a microplate reader. The maximum UV absorption peak was at 300~700nm wavelength. The micro broth dilution method was used to detect the susceptibility of different strains to Ag-PVPNPs and antibiotics. In order to study the relationship between the cytotoxicity of nano silver ion dressings and time, the nano silver ion composite dressings CZ-J1, CZ-J2, CZ-J3, CZ-J4 group samples prepared by the immersion method were selected as test samples, and the test samples were against L02 cells. At different periods, some cloth samples were taken out for anti-adhesion testing. The SPSS19.0 software was used for statistical analysis of the data, and the measurement data were expressed by the mean and standard deviation, and the homogeneity of variance was tested first. The data shows that when combined with 12.5μg/mL Ag-PVP NPs, 2μg/mL gentamicin can completely inhibit the growth of bacteria compared with 50% inhibition rate when acting alone. The results show that nano-silver activated carbon fiber dressing can effectively promote the healing of pressure sore wounds.

Influence of nanosilver in hybrid carriers on morphological and biochemical blood pa-rameters of laying hens

The search for an alternative to antibiotics in poultry has led to a study of the effectiveness of using nanosilver preparations in the production of table eggs. The experiment determined the effect of the drug nanosilver in carriers based on polymer/inorganic hybrids (AgNPs/SPH) on morphological and biochemical parameters of the blood of laying hens. For this, 45 Hy-Line W36 hens were used at the age of 38 weeks, which were randomly divided into three groups. The AgNPs/SPH solution was administered 3 times a month with an interval of 10 days at concentrations of 0.0, 1.0, and 2.0 mg/L (0.0, 0.2 and 0.4 mg per hen per day). The introduction of AgNPs/SPH in doses of 0.2 and 0.4 mg per hen per day three times a month did not have a significant effect on the morphological parameters of the blood. A single dose of 0.2 mg AgNPs/SPH solution per hen per day increased the level of total protein, glucose, cholesterol, as well as the activity of alanine aminotransferase and alkaline phosphatase in the blood serum and decreased albumin, creatinine and gamma-glutamyl transpeptidase activity. Feeding laying hens a solution of nanosilver in a larger dose had a less pronounced effect on these indicators. Two-fold administration of AgNPs/SPH solution at a dose of 0.2 mg per laying hen per day increased only gamma-glutamyl transpeptidase activity in the blood serum, but decreased the level of total activity of protein, albumin, phosphorus, and alkaline phosphatase. At the same time, the drug nanosilver in double dose per day caused an increase in albumin content and alkaline phosphatase activity in the serum of hens. Triple feeding of laying hens with a solution of nanosilver at a dose of 0.2 mg per hen per day did not affect most of the biochemical parameters of serum, but in the double dose increased the content of total protein against the background of lowered cholesterol and gamma-glutamyl transpeptidase activity. With the increase in the frequency of feeding laying hens solutions of nanosilver in carriers based on polymer / inorganic hybrids, the level of severity of their impact on the metabolic profile of serum decreased. The results of research can be the basis for determining the optimal interval of application of nanosilver drugs in poultry, depending on the method of their synthesis and stabilization.

The Application of Nano Silver Argitos as a Final Root Canal Irrigation for the Treatment of Pulpitis and Apical Periodontitis. In Vitro Study.

Background: Endodontic treatment of various forms of pulpitis with variations of root canal system anatomy should be performed with high quality. The use of various antibacterial agents is aimed at maintaining the success of endodontic treatment. The aim of this study was to evaluate the penetration and fixation of the nano-silver solution on the dentinal surface during endodontic treatment. Materials and methods: the study was carried out on 70 extracted single-rooted teeth, randomly divided into two groups. In the teeth of the first group, the smear layer was removed after canal preparation with 17% EDTA solution; in the second group, the smear layer was not removed. In both groups, for the final treatment of the canal, a colloidal 1% solution of нанo серебра nanosilver was used. Samples were cut and prepared for analysis using micro-CT, scanning electron microscopy (SEM), X-ray microanalysis and energy dispersive spectrometry (elemental mapping). Results: in 100% of cases in groups of teeth with a preserved smear layer, the ability of a 1% colloidal solution of nanosilver with particles of 1–2 nm to be fixed on dentin with a removed and preserved smear layer and to leave a film on the dentinal surface was established. In the samples with removed smear layer, silver was found in 73.5% of cases. Conclusion: The nano-silver solution with a particle size of 1–2 nm proved its ability to penetrate the dentinal surfaces and create a final film covering the dentinal surface of the root canal before applying the sealer.

Treatment of Infection and Inflammation Associated with COVID-19, Multi-Drug Resistant Pneumonia and Fungal Sinusitis by Nebulizing a Nanosilver Solution

Treatment of Infection and Inflammation Associated with COVID-19, Multi-Drug Resistant Pneumonia and Fungal Sinusitis by Nebulizing a Nanosilver Solution

Green Plasma Electrochemical Synthesized Colloidal Silver Nanoparticles and Their Antibacterial Activity

Nanosilver solutions of colloidal silver nanoparticles at reasonable price, good quality, and availability are increasingly demanded for the application in agriculture and aquaculture for the prevention and treatment of diseases. In this paper, we have applied a new simple and environmental‐friendly fabrication method based on a plasma electrochemical procedure, where silver nanoparticles are directly formed in the plasma environment from silver ions generated by the electrochemical process from the silver anode. The electrode dissolution rate, the formation percentage, and quality of the silver nanoparticles were examined and evaluated using atomic absorption spectroscopy, electrode mass change, transmission electron microscopy, and UV‐Vis absorption spectroscopy. The silver nanoparticle formation was found of nearly 100% with the rate of about 3.3 mg per minute. Spherical nanoparticles are found in quite homogenous size distribution around about 9.7 nm in the solution. The solution of the plasma synthesized nanosilvers shows better antibacterial property in comparison to that of AgNO3 of the same molar concentration on both normal and antibiotics resistant E. coli strains.

Green preparation of nano‐silver aqueous solution using fructose and evaluation of its antibacterial potential for cut carnation flowers

The green synthesis of nano-silver (NS) has gained increasing attention owing to its cost-effectiveness and environmental friendliness. Herein, a novel one-step green preparation method of stable NS aqueous solution using Tollens reagent as the silver ion source, D-fructose as the reduction agent, and polyvinyl pyrrolidone as the stabilizing and capping agent is reported. The prepared NS solution had a pH value of 7.10, with approximately spherical NS particles in the range of 13.95–87.36 nm. The resulting NS solution was stable under normal temperature, boiling water bath, and acidic environment. The NS solution had a remarkable absorption peak at 410 nm in its ultraviolet–visible spectrum. The dynamic light scattering/Zeta analysis showed the average particle size of the NS aqueous solution was 183.5 nm, polymer dispersion index was 0.282, and the zeta potential of the green synthesized NS was –18.0 mV. Moreover, the NS solution exerted a strong inhibitory effect on the growth of the bacteria isolated from the vase water of cut carnation ‘Prince’ flowers. These findings indicate that the obtained NS solution is potentially a practical and effective antibacterial agent for preserving cut carnations and other cut flowers.

Study on the In vitro and In vivo Antifungal Activities of Nano-silver against Mycoleptodiscus indicus causing Leaf Blight on Lotus in Vietnam

Background: Lotus, Nelumbo nucifera Gaertn is Vietnam’s symbol and Buddhism’s flower and plays an essential part in rural Vietnam’s economy as all aspects of lotus could bring benefits to farmers. But, unfortunately, lotus yield in Vietnam is seriously affected by various plant diseases. Among them, leaf blight is currently emerging as one of the primary diseases devastating lotus crops in Vietnam, in which there are large necrotic parts on lotus leaves, flowers and seeds. Methods: Aloe barbadensis extract was used for synthesizing silver nanoparticles. Leaf blight lotus leaves were collected to isolate pathogenic fungi-infection of isolated pathogenic fungi on the healthy lotus and then identify hidden mold by 28S rRNA sequencing. Determination of in vitro minimal inhibition concentration of nano-silver was conducted according to Azizi. The reduction of disease symptoms and biological characteristics of the treated lotus was observed. Result: Morphological analysis and molecular identification of 28S rRNA sequencing showed that the pathogenic microorganism was Mycoleptodiscus indicus (M. indicus). Both in vitro antifungal activity and in vivo treatment of leaf blight lotus using a nano-silver solution showed that 30 ppm of nano-silver was the minimal inhibition concentration (MIC) for totally eradicating M. indicus growth. This was the first time M. indicus was reported to infect and cause leaf blight on a lotus. Previously, M. indicus was a well-known plant pathogen that could cross-kingdom infect humans and animals. Thus, the fact that lotus is widely cultured in Vietnamese rural could increase the chance for M. indicus to spread; hence, this raised the alarm about its potential harm to plants, humans and animals. And, significantly, it revealed nano-silver as a possible approach to prevent M. indicus.