Silver Nanoparticles In Solution Research Articles

Synthesis and Antibacterial Activity of Ultrasmall Silver Nanoparticles by Pulsed Laser Ablation in Deionized Water

Background: The main objective of this work is the synthesis and evaluation of silver nanoparticles (Ag NPs) by using pulsed laser ablation of a silver (Ag) target in deionized water and examining their antibacterial activity. Methods: Colloidal solutions of silver nanoparticles were prepared with different pulsed laser energies (620, 880, and 1000) mJ of wavelength 1064 nm and frequency 10 Hz. To determine their structure, optical, morphology, elemental composition, and infrared spectra, the synthesized Ag NPs were characterized using various high-throughput analytical techniques such as (UVVis) spectroscopy, transmission electron microgram (TEM), electron dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectra, and Zeta potential. Results: The results show that the properties of synthesized Ag NPs depend much more on the laser energy. The laser energy can be used to control the properties of the prepared nanoparticles. Uniform distributions of spherical ultrasmall Ag NPs with an average size of (3) nm were obtained suspended in deionized water, which is the most effective size for antibacterial activity. However, the result indicated that the ablated Ag NPs were stable for 4 months in deionized water. The antibacterial activity of the colloidal solution of synthesized Ag NPs against Gramnegative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria was then examined using the agar-well diffusion method. Conclusion: It was found that the prepared nanoparticles exhibited strong activity against E. coli and S. aureus bacteria growth. The average zones of inhibition of Ag NPs were found to be about (26) mm for E. coli and (32) mm for S. aureus bacteria.

The Synergism of Silver and Fluoride: A New Arsenal in Caries Management

AbstractTopical anticaries agents are non‐invasive methods to control and prevent dental caries. SDF is a fluoride‐based agent added to the arsenal of caries prevention tools. It has got a lot of attention since its introduction in the 1970s because of its ability to prevent and arrest caries, as well as its excellent antibacterial and anti‐plaque action. SDF reduces acid production by microorganisms, decreases the Streptococcus mutans count, biofilm formation, increases enamel resistance, and promotes dentinal tubule obliteration when applied to the dental surface. SDF also assists in the remineralization of dentin. A biannual application of 38% SDF has been effective at preventing dentin demineralization. This “silver bullet” can be seen as an alternative for caries prevention in special health care needs children which is minimally invasive and safe. Along with the advantages, there are some disadvantages, and work has been carried out to explore the use of silver nanoparticles (SNP) as anticaries agents to shield the teeth from aesthetic damage caused by Silver diamine fluoride. SNPs are identified to have the potential to prevent and inhibit dental caries while not discoloring demineralized dental enamel. SNPs have a greater surface area for interaction with microorganisms than other particles, making them more effective antimicrobial agents. Fluoride combined with SNP solution has a synergistic effect that promotes enamel remineralization while also acting as a bactericidal agent against cariogenic microorganisms. This review aims to bring out the various advantages and disadvantages related to the use of SDF and SNPs to aid in future research.

Photometric evaluations of reverse micellar solutions of gold and silver nanoparticles and their adsorption activity upon the contact with MF-4SK film

Photometric evaluations of reverse micellar solutions of gold and silver nanoparticles and their adsorption activity upon the contact with MF-4SK film

Stability study in selected conditions and biofilm-reducing activity of phages active against drug-resistant Acinetobacter baumannii.

Acinetobacter baumannii is currently a serious threat to human health, especially to people with immunodeficiency as well as patients with prolonged hospital stays and those undergoing invasive medical procedures. The ever-increasing percentage of strains characterized by multidrug resistance to widely used antibiotics and their ability to form biofilms make it difficult to fight infections with traditional antibiotic therapy. In view of the above, phage therapy seems to be extremely attractive. Therefore, phages with good storage stability are recommended for therapeutic purposes. In this work, we present the results of studies on the stability of 12 phages specific for A. baumannii under different conditions (including temperature, different pH values, commercially available disinfectants, essential oils, and surfactants) and in the urine of patients with urinary tract infections (UTIs). Based on our long-term stability studies, the most optimal storage method for the A. baumannii phage turned out to be - 70°C. In contrast, 60°C caused a significant decrease in phage activity after 1 h of incubation. The tested phages were the most stable at a pH from 7.0 to 9.0, with the most inactivating pH being strongly acidic. Interestingly, ethanol-based disinfectants caused a significant decrease in phage titers even after 30s of incubation. Moreover, copper and silver nanoparticle solutions also caused a decrease in phage titers (which was statistically significant, except for the Acba_3 phage incubated in silver solution), but to a much lesser extent than disinfectants. However, bacteriophages incubated for 24h in essential oils (cinnamon and eucalyptus) can be considered stable.

Antimicrobial Nonisocyanate Polyurethane Foam Derived from Lignin for Wound Healing.

Medical dressings, as a cover for wounds, can replace damaged skin in the wound healing process to play a temporary barrier role, avoid or control wound infection, and provide a favorable environment for wound healing. Therefore, there is an urgent need for medical antimicrobial dressings for the treatment of chronic wounds. Although traditional polyurethane foam has been widely used in medical dressings, conventional polyurethane foams are primarily prepared using nonbiocompatible isocyanate-based compounds, which are potentially hazardous for both operators and applications in the medical field. Here, we propose nonisocyanate polyurethane foams naturally derived from lignin by enzymatic lignin alkylation, cyclic carbonation modification, and polymerization with diamine and the addition of a blowing agent. Silver nanoparticle solution was added during foaming to confer antimicrobial properties. This lignin-based nonisocyanate polyurethane/silver composite foam (named NIPU foam-silver) using a green synthesis method has good mechanical properties, which can be used to manufacture polyurethane/silver foams, and thermal and antimicrobial properties. Notably, NIPU foam-Ag showed more than 95% bactericidal efficacy against both Escherichia coli and Staphylococcus aureus within 4 h. Evaluation of in vitro wounds in mice showed that this antimicrobial composite foam rapidly promotes wound healing and repairs damaged tissue. This suggests that this biobased biodegradable antimicrobial foam has significant scope for clinical applications in wound management.

Silica supported biosynthesized silver nanoparticles as effective adsorbent and photocatalyst for removal of methylene blue from water

The silica supported silver nanoparticles (Ag@SG) were prepared by wet impregnation of silica gel (SG) using different concentrations of biogenic silver nanoparticles (AgNPs; 0.25–5 mM) solution, prepared from Cicer arientinum pod extract. Among them, the Ag@SG composite prepared by using 1.25 mM AgNPs solution (Ag1.25@SG) was found to contain only Ag0 species as nanoparticles, whereas the samples prepared by higher concentrations contained Ag0 as well as Ag+ (silver oxide) species. All the Ag@SG composites including SG, exhibited good adsorption capacity for a cationic dye (methylene blue; MB) in water. However, Ag1.25@SG having only Ag0 species exhibited higher photocatalytic activity for degradation of MB under visible light irradiation as compared to other composites. The study reveals that the plasmonic Ag0 species supported on silica are catalytically more active than Ag+ species. Furthermore, the AgNPs (Ag0) in supported form exhibits much higher (∼5-fold) photocatalytic activity than unsupported AgNPs. The synergistic effect of adsorption property of silica surface and plasmonic photocatalytic activity of AgNPs in the synthesized composites was found to be effective for the removal of MB. In addition, the fine dispersion of AgNPs on internal surface of silica provides better activity for photocatalysis. The study shows that this material is a promising adsorbent as well as photocatalyst for the removal of dyes from water.

Detection of the effect of silver nanoparticles prepared by using extract leaves Prosperis juliflora on pathogenic fungus Trichophyton tonsurans isolated from human scalp

The silver nanoparticles were prepared using Prosopis juliflora leaf extract and extracted from trees in Kirkuk city and showed that the silver nitrate solution in 1 mm turned its color brown which will be preliminary evidence of the formation of nanoparticles. The UV and visible absorption spectrum of a solution of silver nanoparticles was tested as a second step in confirming the formation of the particles, and it was found that they were present at the wavelength (440) nm, where it turned out that the peaks of X-ray diffraction were at (111), (220), (311) at angles (31.77, 48.11, 54.21) respectively. Trichophyton tonsurans were isolated from the scalp of a person with ringworm from Kirkuk General Hospital. The fungus was diagnosed on the basis of the phenotypic and microscopic characteristics and hair penetration. it was found that the solution of silver nanoparticle had a clear inhibitory effect on the fungus Trichophyton tonsurans. The highest and lowest inhibitor concentration reached 90% and the highest inhibitor concentration was 100 % Also, the ratios of the silver nanoparticles effects on the growth and production of fungi spores were determined.

Antibacterial Activity of Root Repair Cements in Contact with Dentin-An Ex Vivo Study.

This study assessed the antibacterial characteristics of the dentin/material interface and dentin surfaces exposed to experimental hydraulic calcium silicate cement (HCSC) with or without bioactive glass (BG) replacement (20% or 40%) or mixed with a silver nanoparticle (SNP) solution (1 or 2 mg/mL), and Biodentine, TotalFill BC RRM putty and Intermediate Restorative Material (IRM). Human root dentin segments with test materials were assessed at 1 or 28 days. In one series, the specimens were split to expose the dentin and material surfaces. A 24 h direct contact test was conducted against three-day established Enterococcus faecalis and Pseudomonas aeruginosa monospecies biofilms. In another series, the dentin/material interface of intact specimens was exposed to biofilm membranes for 3 days and the antibacterial activity was assessed via confocal microscopy. The interface was additionally characterised. All one-day material and dentin surfaces were antibacterial. Dentin surfaces exposed to HCSC with 40% BG-replacement, Biodentine and IRM had decreased antibacterial properties compared to those of the other cements. The HCSC mixed with a 2 mg/mL SNP solution had the highest antimicrobial effect in the confocal assay. The interfacial characteristics of HCSCs were similar. The test materials conferred antibacterial activity onto the adjacent dentin. The BG reduced the antibacterial effect of dentin exposed to HCSC; a 2 mg/mL SNP solution increased the antibacterial potential for longer interaction periods (three-day exposure).

The effect of silver nanoparticles in addition to sodium fluoride on remineralization of artificial root dentin caries.

Silver nanoparticle was developed to overcome the drawback of silver diamine fluoride. However, evidence is limited, especially in root caries. The aim of this study was to evaluate the remineralization effect of silver nanoparticles on root caries. Fifty-five root human dentin slices size 5 × 5 mm2 from patients aged over 60 years old were immersed in demineralized solution to create artificial caries. Specimens were allocated into five groups according to the remineralizing agents: silver diamine fluoride (SDF), silver nanoparticles solution (AgNPs), silver nanoparticle solution followed by sodium fluoride varnish (AgNPs+NaF), sodium fluoride varnish (NaF), and tap water. After 8 days of pH-cycling challenge, the microhardness test, lesion depth evaluation, dentin surface morphology, and elemental analysis were performed. Data was analysed using F-test One-way ANOVA followed by Tukey's post hoc test and paired T-test. All test groups demonstrated a significantly higher microhardness value and lower lesion depth compared with the control group. AgNPs+NaF and NaF-treated groups showed lower efficacy than SDF. Crystal precipitation was presented in all groups composed of silver. Addition of fluoride varnish did not benefit for silver nanoparticles in preventing further demineralization. SDF provides the highest effectiveness in elderly root carious dentin.

Synthesis of Metal Nanoparticles via Pulicaria undulata and an Evaluation of Their Antimicrobial, Antioxidant, and Cytotoxic Activities

Nanoparticle engineering via plants (green synthesis) is a promising eco-friendly technique. In this work, a green protocol was applied to the preparation of silver, zinc, and selenium nanoparticle solutions supported by the extracted aerial parts of Pulicaria undulata. The formation of nanoparticles in the solution was characterized using phytochemical analysis, and UV-visible, TEM, and zeta-potential spectroscopy. In addition, various biological activities were investigated for the extract of P. undulata and the produced nanoparticles (selenium, silver, and zinc), including antioxidant, antimicrobial, and cytotoxic activities. The volatile components of the extracted constitute verified the fact that twenty-five volatile components were characterized for the majority of abundant categories for the fatty acids, esters of fatty acids (59.47%), and hydrocarbons (38.19%) of the total area. The antioxidant activity of P. undulata extract and metal nanoparticles was assessed using DPPH assay. The results indicated reduced potency for the metal nanoparticles’ solutions relative to the results for the plant extract. The cytotoxicity of the investigated samples was assessed using an MTT assay against various tumor and normal cell lines with improved cytotoxic potency of the solutions of metal nanoparticles, compared to the plant extract. The antimicrobial activity was also estimated against various bacterial and fungal species. The results confirmed amended potency for inhibiting the growth of microbial species for the solutions of metal nanoparticles when compared to the extracted aerial parts of the plant. The present study showed that green synthetized nanoparticles using P. undulata have various potential bioactivities.

STUDY OF THE ANTISTATIC PROPERTIES OF MATERIALS TREATED WITH COLLOIDAL COMPOSITIONS BASED ON METAL NANOPARTICLES

The article provides a short overview of the application of metal nanoparticles in the textile indus- try, describes their properties and application`s fields. The definitions of electrification, electrostatic field, electric charge density are given. The application of processing of fabrics by polyurethane dispersion and metal nanoparticles in technological processes of textile materials finishing is justified. The objects of the study are cotton fabric`s samples with addition of synthetic fibres, colloidal solutions of silver and copper nanoparticles, aqueous polyurethane dispersion. The antistatic properties of the fabrics have been studied. The electrostatic field intensity of the samples was measured on the device ST-01, with the density of the electric charge calculating according to the intensity values. It has been experimentally established, that the processing of fabrics by solutions of nanoparticles of metals contributes to reduction of intensity of their electrostatic field to 65 %, compared with the initial samples. It is noted that treatment of fabrics by polyure- thane dispersion in combination with copper nanoparticles gives no clear antistatic properties to the blended fabrics.

Colorimetric Sensor Based AgNPs for the Detection of Cyanide using UV‐Vis Spectrophotometry

AbstractCyanide (CN−) is known to be a very harmful ion that may accumulate in the air, soil and water, and become a critical risk to organisms, even at trace levels. Hence, it is very critical to develop sensitive and accurate analytical methods for the determination of this anion. In this study, a highly sensitive and simple approach was developed for the quantitative determination of cyanide by UV‐Vis spectrophotometry with the aid of synthesized silver nanoparticles (AgNPs) solutions. AgNPs are promising probes frequently used in the determination of both organic and inorganic pollutants. The AgNPs were prepared by reducing silver nitrate (AgNO3) with sodium borohydride (NaBH4) in the presence of Triton X‐100 as a stabilizer. The UV‐Vis absorption spectra showed that the interaction between cyanide ions and AgNPs made significant decreases in the absorption peak of the surface plasmon resonance (SPR) band at 405 nm. The developed colorimetric sensor exhibited exceptional sensing towards cyanide ions with good linearity in the range of 0.5 and 3.5 mM. The limit of detection (LOD) and the limit of quantification (LOQ) were estimated as 0.09 and 0.29 mM, respectively. Moreover, the proposed colorimetric method was successfully applied to different water samples.

Influence of Radical Scavenger on Radiation Synthesis of Graphene Oxide/TiO2 Nanotubes/Ag Nanoparticles Nanocomposites and Their Dye Photodegradation Efficiency

Aqueous solutions of graphene oxide (GO), TiO2 nanotubes (TNTs), and silver nanoparticles (AgNPs) were synthesized through a facile, single-step radiolytic method at room temperature and ambient pressure. The resulting material, referred to as GO-TNTs-AgNPs (GTA), was investigated for its potential application in the photodegradation of Rhodamine-B (RhB) dye. This synthesis process relies on the interaction of high-energy gamma rays from a 60Co source with the water in the aqueous solutions. The main objective of this study was to evaluate the effect of irradiation dose and the presence of polyethylene glycol (PEG) solution on the combination within the nanocomposite materials. The inefficiency of GTA synthesis experimentally was in agreement with the hydroxyl radical (HO•) scavenger. Then, the irradiated materials were structurally characterized using various spectroscopic methods (Fourier transform infrared (FTIR), X-ray diffraction (XRD), Raman spectroscopy, and ultraviolet-visible absorption (UV–Vis)). Scanning electron microscopy (SEM) studies reveal the variable morphology of nanocomposites. GTA samples in water exhibited significantly higher degradation efficiency on Rhodamine B dye under natural sunlight irradiation conditions.

Laser liquid ablation for silver nanoparticles synthesis and conjugation with hydroxychloroquine for Covid-19 treatment

Synthesis, characterization, and anchorage studies of pristine silver nanoparticles were achieved. That would later be followed by the conjugation of the synthesized silver nanoparticles with hydroxychloroquine, a compound that is commonly identified as active against plasmodium, a malaria-causing agent. The synthesis of the pristine silver nanoparticles was achieved through laser ablation, a physical method. To achieve different concentrations and sizes of the nanoparticles, various parameters such as time and pulse repetition frequencies were varied. The base medium of the ablation was distilled water of 10 ml for every process of ablation. The laser ablation technique used proved effective in the production of silver nanoparticles spherical in shape and of the size range between 16 nm and 30 nm as deduced from Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) characterization techniques. EDS analysis confirmed the presence of AgNPs in the synthesized solution of silver nanoparticles, while the UV–Vis results showed that the absorption peak of AgNPs occurred at 403 nm. Through these findings, the use of laser ablation, a physical technique in the synthesis of AgNPs, is shown to be cost-effective and environmentally friendly with the properties of the nanoparticles proving to be effective for biomedical applications later in this work.

Water Purification Using Ceramic Pots Water Filter

In this study, ceramic pot filters are made from clay and burn-out materials (sawdust) that give pore sizes capable of capturing contaminants. Manufacturing specifications were selected to achieve some results. Clay and sawdust are mixed in a 50% volume ratio each and sawdust was subjected to hot water extraction to give a treated sample. Filters produced comprised of untreated, treated, and a mixture of treated and untreated sawdust samples, some of which were dipped in a solution of silver nanoparticles while others were not dipped (treated undipped, treated dipped, mixed dipped, mixed undipped, untreated undipped, untreated dipped). The effectiveness of the produced filters for the removal of contaminants such as dissolved solids, turbidity, and metals was tested using water collected from the Ikeji Arakeji River in Osun, Nigeria. The results showed the filter with treated sawdust undipped in a solution of silver nano gave the best result in the removal of the contaminants. Also, the filter with the mixtures of treated and untreated sawdust gave a better result compared to the standard. While the standard gave a better result than the untreated undipped ceramic filter pot. In conclusion, with proper cleaning and maintenance of the filters, they can effectively provide treated water suitable for drinking to rural people affected by polluted water sources.

Robust conductive skin hydrogel e-skin constructed by top–down strategy for motion-monitoring

The construction of biomass-based conductive hydrogel e-skins with high mechanical properties is the research hotspot and difficulty in the field of biomass materials. Traditional collagen-based conductive hydrogels, constructed by the typical “bottom–up” strategy, normally have the incompatible problem between high mechanical property and high collagen content, and the extraction of collagen is often necessary. To solve these problems, inspired by the high mechanical properties and high collagen content of animal skins, this work proposed a “top–down” construction strategy, in which the extraction of collagen was unnecessary and the skin collagen skeleton (SCS) with the 3D network structure woven by natural collagen fibers in goatskin was preserved and used as the basic framework of hydrogel. Following a four-step route, namely, pretreatment → soaking in AgNPs (silver nanoparticles) solution → soaking in the mixed solution containing HEA (2-hydroxyethyl methacrylate) and AlCl3 → polymerization, this work successfully achieved the fabrication of a new skin-based conductive hydrogel e-skin with high mechanical properties (tensile strength of 2.97 MPa, toughness of 6.23 MJ·m−3 and breaking elongation of 428%) by using goatskin as raw material. The developed skin hydrogel (called PH@Ag) possessed a unique structure with the collagen fibers encapsulated by PHEA, and exhibited satisfactory adhesion, considerable antibacterial property, cytocompatibility, conductivity (3.06 S·m−1) and sensing sensitivity (the maximum gauge factor of 5.51). The PH@Ag e-skin could serve as strain sensors to accurately monitor and recognize all kinds of human motions such as swallowing, frowning, walking, and so on, and thus is anticipated to have considerable application prospect in many fields including flexible wearable electronic devices, health and motion monitoring.Graphical abstract

Synthesis, structural, and optical properties of (Ag/ZnS) core–shell nanostructures and their applications to polycrystalline silicon solar cells

The present work focuses on the two-step chemical synthesis of Ag/ZnS nanoparticles as core–shell nanoparticles. Various techniques were used to characterize nanoparticles, including UV–Vis spectroscopy, Dynamic Light Scattering, Transmission Electron Microscopy, Fourier Transform Infrared Spectroscopy, and a Solar Simulator. UV–Vis spectral analysis of Ag/ZnS core–shell nanoparticles at 450, 469, and 498 nm reveals broad plasmon resonance bands. The solution of silver nanoparticles was redshifted by increasing its concentration. Core and shell images obtained from each nanoparticle show different contrasts, indicating that the core and shell materials differ. Infrared spectroscopy confirmed the presence of ZnS NPs around AgNPs. Incorporating Ag/ZnS into polycrystalline silicon solar cells has improved efficiency from 13.02 to 14.29%.

Optical Characteristics of Silver Nanoparticles Obtained Using Artemisia tilesii Ledeb. "Hairy" Root Extracts With High Flavonoid Content

Background. "Hairy" roots can be used for production of plant-derived secondary metabolites, such as flavonoids, which have antioxidant and reducing properties. It seems promising to use the process of silver nanoparticles formation as a method of determining the level of reducing power. This approach allows simul­taneously to obtain nanoparticles with different biological activity and evaluate the reducing potential of dif­ferent plants. Objective. The aim of the study was to determine the dependence of optical properties (ultraviolet/visible spectroscopy, UV-Vis spectra) of solutions of silver nanoparticles obtained using wormwood "hairy" root extracts on the content of flavonoids as compounds with reducing activity. Methods. Four Artemisia tilesii “hairy” root lines from the collection of the Institute of Cell Biology and Genetic Engineering NAS of Ukraine were grown for five weeks in liquid 1/2 MS medium with 20 g/l sucrose. "Hairy" roots were homogenized in 70% ethanol, the extracts were centrifuged, total flavonoid content was determined, and extracts were used for the silver nanoparticles preparation via reduction of Ag+ to Ag0 from AgNO3. UV-Vis spectra at 300–600 nm range were recorded right after colloid solution preparation, in five, and in nine days. Results. Total flavonoid content varied from 4.01 ± 0.39 to 15.37 ± 1.08 mg RE/g FW. The UV-Vis spectra curves of absorption increased with the course of time, mostly from day 0 to day 5. At this period, absorption at 370–500 nm wavelength increased almost twofold. The peak absorption of all samples was detected at 440 nm, and the maximum values at the wavelength of 440 nm correlated with the content of flavonoids. This correlation did not change over time. Conclusions. The optical properties of silver nanoparticles colloid solutions obtained using A. tilesii "hairy" root extracts correlated with the total flavonoid content of the samples. Even though the absorbance of the colloid solutions increased with time, those increases correlated with flavonoid content as well. The determination of the optical properties of AgNPs colloid solution can be used as a convenient way of quickly comparing the reducing ability of extracts both right after the formation of a colloidal solution and after some time of its storage.

Electric Discharge Synthesis of Colloidal Silver Nanoparticle Solutions Using Various Modifiers for Immobilization on the Surface of Track-Etched Membranes

Electric Discharge Synthesis of Colloidal Silver Nanoparticle Solutions Using Various Modifiers for Immobilization on the Surface of Track-Etched Membranes

Ecofriendly fabrication of silver nanoparticles using quince petal extract and its antibacterial properties against fire blight disease

Fire blight of pear trees is a devastating disease which is caused by the bacterium namely as Erwinia amylovora (Burrill 1882). Current chemical control methods employed for fire blight disease are periodic applications of copper compounds and streptomycin, especially when environmental conditions are favorable for the infection. Silver nanoparticles (SNPs) are nanoparticles of silver with 1–100 nm size, which are synthesized via different chemical and biological methods. They have been shown to have antibacterial activity against many human and animal pathogens. In this study, silver nanoparticles (SNPs) with an average size of about 25 nm were determined using quince petal aqueous extract. The physicochemical properties of the resulting SNPs were characterized using UV–Vis spectroscopy, X-ray diffraction technique (XRD), transmission electron microscope (TEM), energy dispersive X-ray (EDAX) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS). The SNPs inhibited the growth of E. amylovora in culture media and in-planta. The disease severity was reduced by 80 % and 74 % in pear blossoms and immature fruits treated with 100 μg/mL SNP solution, respectively. This work demonstrates that Cydonia oblonga petal extract is a feasible medium for the synthesis of silver nanoparticles which can be used for the control of fire blight disease.