Copolymerization of Quinazolinone Derivatives With Styrene, Methyl Methacrylate and Their Silver Nanocomposites for Biological Applications

Reaction of 2-mercapto-3-phenylquinazolin-4(3H)-one (MPQ) with both 4-vinyl benzyl chloride and allyl bromide furnished the reactive heterocyclic monomers 3-phenyl-2-((4-vinylbenzyl) thio) quinazolin-4(3H)-one (PVTQ) and 2-(allylthio)-3-phenylquinazolin-4(3H)-one (APQ), respectively. Copolymerization of PVTQ monomer with styrene and methyl methacrylate in the presence of 2,2′-azobisisobutyronitrile (AIBN) afforded the copolymers PS-co-PPVTQ and PMMA-co-PPVTQ, respectively. Similarly, copolymerization of monomer APQ with styrene and methyl methacrylate (MMA) afforded the copolymers PS-co-PAPQ and PMMA-co-PAPQ, respectively. The resulted copolymers were characterized by using FT-IR, 1H-NMR and GPC techniques. Silver nanocomposites of PS, PMMA, PS-co-PPVTQ, PMMA-co-PPVTQ, PS-co-PAPQ and PMMA-co-PAPQ were synthesized by the addition of silver nitrate into the polymer solution. The reduction of silver ions into silver nanoparticles was performed in DMF and water. Thermogravimetric (TGA) analysis was used to determine the thermal stability of the copolymers and their silver nanocomposites. The X-ray diffraction (XRD) analysis indicated the amorphous structures of the co-polymers and confirmed the formation of silver nanoparticles. The antitumor and antibacterial activities were screened for the copolymers and enhanced by the formation of their silver nanocomposites. In vivo antitumor activity in Ehrlich Ascitic Carcinoma (EAC) mice model showed that PS-co-PPVTQ/Ag NPs, PMMA-co-PPVTQ/Ag NPs, and PMMA-co-PAPQ/Ag NPs displayed promising inhibitory effects against EAC and induce apoptosis against MCF-7 cells.

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Silver nanoparticles used to counter Monilinia fructicola fungicide-resistance and reduce fungicide environmental footprint

10.5194/egusphere-egu21-9285 ◽

2021 ◽

Author(s):

Constantinos Chrysikopoulos ◽

Anastasios A. Malandrakis ◽

Nektarios Kavroulakis ◽

Anthi Stefanarou

Keyword(s):

Silver Nanoparticles ◽

Control Plant ◽

Resistance Mutation ◽

Silver Ions ◽

Apple Fruit ◽

Ag Nps ◽

Gene Target ◽

Benzimidazole Fungicides

<div>The potential of silver nanoparticles (Ag-NPs) to control plant pathogen Moniliafructicola and to deter environmental contamination by reducing fungicide doses was evaluated in vitro and in vivo. &#160;Fungitoxicity screening of&#160;M. fructicola&#160;isolates resulted in the detection of 18 benzimidazole-resistant (BEN-R) isolates with reduced sensitivity to fungicides &#160;thiophanate methyl (TM)&#160; and carbendazim. All resistant isolates caried the E198A resistance mutation in their &#946;-tubulin gene, target site of the benzimidazole fungicides.&#160;Ag-NPs could effectively control both sensitive (BEN-S) and resistant isolates while the combination of Ag-NPs with TM significantly enhanced their fungitoxic effect both in vitro&#160;and in apple fruit tests. The positive correlation observed between Ag-NPs and TM+Ag-NPs treatments indicates a mixture-enhanced Ag-NPs activity/availability as a possible mechanism of synergy. No correlation between Ag-NPs&#160; and AgNO3&#160;could&#160; be found suggesting difference(s) in the fungitoxic mechanism of action between Nps and their bulk/ionic counterparts. Indications of the involvement of energy (ATP) metabolism in the mode of action of Ag-NPs were also evident by the synergy observed between Ag-NPs and the oxidative phosphorylation-uncoupler fluazinam (FM) against both BEN-R and BEN-S phenotypes. The role of silver ions release on the inhibitory action of Ag-NPs against the fungusis probably limited since the AgNPs/NaCl combination enhanced fungitoxicity, a fact that could not be justified by the expected binding of silver with chlorine ions. Concluding, Ag-NPs can be effectively used as a means of controlling both BEN-S and BEN-R M.&#160;fructicola&#160;isolates while&#160;their combination with conventional fungicides should aid anti-resistant strategies and reduce the environmental impact of synthetic fungicides by reducing effective doses to the control the pathogen.</div>

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Development of Plant-Mediated Silver Nanoparticles & Their Pharmacological Evaluation

10.21203/rs.3.rs-1224222/v1 ◽

2022 ◽

Author(s):

Shanker Kalakotla ◽

Geetha P ◽

Ahmadi Banu ◽

Shamshe Shaik

Keyword(s):

Plant Extract ◽

Dose Range ◽

Silver Ions ◽

Xrd Analysis ◽

Treated Group ◽

Diabetic Rats ◽

Significant Inhibition ◽

Synthesis Process ◽

Ag Nps

Abstract Diabetes is among the most common debilitating and non-transferable diseases on the planet. The idea of using nanoparticles as a drug to treat diabetes mellitus seems intriguing. The Ag nanoparticles (Ag NPs) were effectively produced utilizing Moringa olifera (family: Moringaceae) plant extract employing a simple, cheaper, faster, and environmentally friendly green synthesis process. The antidiabetic effect of the produced Ag NPs was also tested in vivo. In the presence of plant extract, silver nitrate was converted to silver ions (Ag). XRD, FTIR, UV, XPS, and HRTEM studies characterize the formed Ag NPs. Ag NPs that have been biosynthesized, crystal nature was confirmed through XRD analysis and confirmed by UV-visible spectroscopy. FT-IR spectra were used to verify the presence of various functional groups in the biomolecules, forming and stabilizing the nanoparticles. The size of the NPS was in the range of 20-40 nm determined by HRTEM. The induction of diabetes using STZ showed increased blood glucose, cholesterol, triglycerides, LDL, VLDL, massive loss in body weight. These changes were reversed following the treatment of diabetic rats for 28 days and showed significant inhibition (p < 0.001) at a dose range of 0.2 mg/kg leaf extract and 0.2 mg/kg Ag NPs compared with the extract-treated group. These obtained results suggested that plant-mediated Ag NPs have shown promising antidiabetic and anti-hyperlipidemic activity compared to the crude extract.

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Green Biosynthesis of Silver Nanoparticles Using Leaf Extract of Carissa carandas L. and Their Antioxidant and Antimicrobial Activity against Human Pathogenic Bacteria

Biomolecules ◽

10.3390/biom11020299 ◽

2021 ◽

Vol 11 (2) ◽

pp. 299

Author(s):

Reetika Singh ◽

Christophe Hano ◽

Gopal Nath ◽

Bechan Sharma

Keyword(s):

Silver Nanoparticles ◽

Pathogenic Bacteria ◽

Leaf Extract ◽

Room Temperature ◽

Xrd Analysis ◽

Antibacterial Activities ◽

Effect Of Temperature ◽

Human Pathogenic Bacteria ◽

Carissa Carandas ◽

Antioxidant And Antimicrobial Activity

Carissa carandas L. is traditionally used as antibacterial medicine and accumulates many antioxidant phytochemicals. Here, we expand this traditional usage with the green biosynthesis of silver nanoparticles (AgNPs) achieved using a Carissa carandas L. leaf extract as a reducing and capping agent. The green synthesis of AgNPs reaction was carried out using 1mM silver nitrate and leaf extract. The effect of temperature on the synthesis of AgNPs was examined using room temperature (25 °C) and 60 °C. The silver nanoparticles were formed in one hour by stirring at room temperature. In this case, a yellowish brown colour was developed. The successful formation of silver nanoparticles was confirmed by UV–Vis, Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) analysis. The characteristic peaks of the UV-vis spectrum and XRD confirmed the synthesis of AgNPs. The biosynthesised AgNPs showed potential antioxidant activity through DPPH assay. These AgNPs also exhibited potential antibacterial activity against human pathogenic bacteria. The results were compared with the antioxidant and antibacterial activities of the plant extract, and clearly suggest that the green biosynthesized AgNPs can constitute an effective antioxidant and antibacterial agent.

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Silver Nanoparticles Stimulates Spermatogenesis Impairments and Hematological Alterations in Testis and Epididymis of Male Rats

Molecules ◽

10.3390/molecules25051063 ◽

2020 ◽

Vol 25 (5) ◽

pp. 1063 ◽

Cited By ~ 4

Author(s):

Janet Olayemi Olugbodi ◽

Oladipupo David ◽

Ene Naomi Oketa ◽

Bashir Lawal ◽

Bamidele Joseph Okoli ◽

...

Keyword(s):

Silver Nanoparticles ◽

Hematological Parameters ◽

Silver Ions ◽

Thiol Group ◽

Sperm Parameters ◽

Male Rats ◽

Ag Nps ◽

Hematological Indices ◽

Electron Microscopies ◽

Pharmaceutical Application

The potential pharmaceutical application of nanoparticles has led to the toxicity within the male reproductive system. In the present study, the effects of silver nanoparticles (Ag-NPs) on hematological parameters, free radical generation, antioxidant system, sperm parameters, and organ histo-morphometry in male rats were investigated. Ag-NPs were produced by the reduction of silver ions, while the formation of which was monitored by UV–visible spectrophotometry. Zeta potential, transmission, and scanning electron microscopies were applied for the characterization of AgNPs. A total of 30 rats were divided into 6 groups and were sub-dermally exposed to Ag-NPs at the dosage of 0 (control), 10, and 50 mg/kg bodyweight (bw) doses for either 7 or 28 days. Ag-NP administration altered hematological indices and caused dose-dependent decreases in sperm motility, velocity, kinematic parameters, concentrations of luteinizing hormone, follicle-stimulating hormone, and testosterone. In the epididymis and testis, the concentrations of malondialdehyde and peroxide increases while superoxide dismutase, catalase, reduced glutathione, and total thiol group decreases. These findings suggest that Ag-NP triggered hormonal imbalance and induce oxidative stress in testis and epididymis; which negatively affect sperm parameters of male rats.

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Bioinspired Synthesis of Acacia senegal Leaf Extract Functionalized Silver Nanoparticles and Its Antimicrobial Evaluation

Journal of Nanomaterials ◽

10.1155/2020/6474913 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Edwina Olohirere Uzunuigbe ◽

Abidemi Paul Kappo ◽

Sixberth Mlowe ◽

Neerish Revaprasadu

Keyword(s):

Silver Nanoparticles ◽

Colour Change ◽

Silver Ions ◽

Antibacterial Activities ◽

Cubic Phase ◽

X Ray Diffraction ◽

Leaf Extracts ◽

Acacia Senegal ◽

Transmission Electron ◽

Antimicrobial Evaluation

Synthesizing nanoparticles with the less environmentally malignant approach using plant extract is of great interest; this is because most of the chemical approaches can be very costly, toxic, and time-consuming. Herein, we report the use of Acacia senegal leaf extracts to synthesize silver nanoparticles (AgNPs) using an environmentally greener approach. Silver ions were reduced using the bioactive components of the plant extracts with observable colour change from faint colourless to a brownish solution as indication of AgNP formation. The structural properties of the as-synthesized AgNPs were characterized using powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and UV-Vis absorption spectrum. Antimicrobial assessment of the as-synthesized AgNPs was explored on some strains of gram-positive and gram-negative bacteria. The obtained results indicate that the as-synthesized AgNPs are pure crystallite of cubic phase of AgNPs, fairly dispersed with a size range of 10–19 nm. The AgNPs were found to be small in size and exhibit significant antibacterial activities, suggesting that the as-synthesized AgNPs could be used in the pharmaceutical and food industries as bactericidal agents.

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Evolution Analysis of Silver Nanoparticles Synthesised by Lactam Reduction: A Case Study of ϵ-Caprolactam

Australian Journal of Chemistry ◽

10.1071/ch18148 ◽

2018 ◽

Vol 71 (8) ◽

pp. 587 ◽

Cited By ~ 1

Author(s):

Na Zhang ◽

Jianping Duan ◽

Dajiang Zhao ◽

Guisheng Yang

Keyword(s):

Silver Nanoparticles ◽

Size Distribution ◽

Ostwald Ripening ◽

Silver Ions ◽

Reducing Agents ◽

Ag Nps ◽

Second Stage ◽

Evolution Analysis ◽

Ostwald Ripening Mechanism

Without using protecting agent and solvent, silver nanoparticles (Ag NPs) were synthesised by using lactams as reducing agents. Being the most commercially available lactam, ϵ-caprolactam (CL) was taken as a model to illustrate the evolution of Ag NPs in the medium of lactams. The results showed that there were two different stages involved in the Ag NP evolution process. In the first stage, particles were stabilised against further coalescence at a smaller size (< 5 nm) because of face-bound CL. In the second stage, the Ostwald ripening mechanism cooperated with continuous reduction of residual silver ions, which resulted in the resultant particles being distributed with different size distribution. The participation of CL in the reducing and protecting procedures raised a complex evolution of Ag NPs.

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Antimicrobial Potential of Silver Nanoparticles Synthesized Using Medicinal Herb Coptidis rhizome

Molecules ◽

10.3390/molecules23092268 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2268 ◽

Cited By ~ 12

Author(s):

Garima Sharma ◽

Ju-Suk Nam ◽

Ashish Sharma ◽

Sang-Soo Lee

Keyword(s):

Silver Nanoparticles ◽

Aqueous Extract ◽

Inductively Coupled Plasma ◽

Antimicrobial Property ◽

Spherical Shape ◽

Silver Ions ◽

Average Diameter ◽

Xrd Analysis ◽

Visible Absorption ◽

Biosynthesized Agnps

Coptidis rhizome contains several alkaloids that are bioactive agents of therapeutic value. We propose an eco-friendly method to synthesize biocompatible silver nanoparticles (AgNPs) using the aqueous extract of Coptidis rhizome. Silver ions were reduced to AgNPs using the aqueous extract of Coptidis rhizome, indicating that Coptidis rhizome can be used for the biosynthesis of AgNPs. The time and the concentration required for conversion of silver ions into AgNPs was optimized using UV-absorbance spectroscopy and inductively coupled plasma spectroscopy (ICP). Biosynthesized AgNPs showed a distinct UV-Visible absorption peak at 420 nm. ICP analysis showed that the time required for the completion of biosynthesis was around 20 min. Microscopic images showed that nanoparticles synthesized were of spherical shape and the average diameter of biosynthesized AgNPs was less than 30 nm. XRD analysis also confirmed the size of AgNps and revealed their crystalline nature. The interaction of AgNPs with phytochemicals present in Coptidis rhizome extract was observed in FTIR analysis. The antimicrobial property of AgNPs was evaluated using turbidity measurements. Coptidis rhizome-mediated biosynthesized AgNPs showed significant anti-bacterial activities against Escherichia coli and Staphylococcus aureus that are commonly involved in various types of infections, indicating their potential as an effective anti-bacterial agent.

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Green Synthesis of Silver Nanoparticles in the Presence of Polysaccharide: Optimization and Characterization

Journal of Nanomaterials ◽

10.1155/2020/3051308 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 10

Author(s):

Margarita I. Skiba ◽

Victoria I. Vorobyova ◽

Alexander Pivovarov ◽

Natalya P. Makarshenko

Keyword(s):

Silver Nanoparticles ◽

Sodium Alginate ◽

Xrd Analysis ◽

Face Centered Cubic ◽

Colloidal Solutions ◽

Ag Nps ◽

Sem Images ◽

Spherical Powder ◽

Stabilizing Agent ◽

Vis Spectroscopy

The process of obtaining aqueous solutions of silver nanoparticles with the use of a low-temperature nonequilibrium contact plasma and stabilizing agent—polysaccharide (sodium alginate)—has been examined. The synthesized Ag NPs were characterized by using UV-Vis spectroscopy, dynamic light scattering (DLS), scanning electron microscope (SEM), and XRD analysis. The effect of concentration of Ag+, sodium alginate, duration of processing by plasma discharge, and pH of liquid on the production of silver nanoparticles has been studied. The results demonstrated that synthesis provides the formation of silver nanoparticles for investigated concentrations of Ag+ (0.3-3.0 mmol/l) and 5.0 g/l Na-Alg (pH=7–10) within 1–5 minutes. From the SEM images, the silver nanoparticles are found to be almost spherical. Powder XRD results reveal that Ag nanoparticles have a face-centered cubic crystal structure. Zeta potential of plasma-chemically obtained colloidal solutions at various concentrations of Ag+ ions and stabilizing agent varies from −32.8 to −39.3 mV, indicating the moderate stability of synthesized nanoparticles.

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In Vivo Toxicity of Silver Nanoparticles and Silver Ions in Zebrafish (Danio rerio)

Journal of Toxicology ◽

10.1155/2012/293784 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 98

Author(s):

Katrine Bilberg ◽

Mads Bruun Hovgaard ◽

Flemming Besenbacher ◽

Erik Baatrup

Keyword(s):

Silver Nanoparticles ◽

Danio Rerio ◽

Silver Ions ◽

Nacl Solution ◽

Median Lethal Concentration ◽

Ph Variation ◽

Minor Influence ◽

Influence Of Water ◽

Related Stress

The influence of water chemistry on characterised polyvinyl pyrrolidone- (PVP-) coated silver nanoparticles (81 nm) was investigated. NaCl solution series of 100–800 mg L−1lead to initial and temporal increase in nanoparticles size, but agglomeration was limited. pH variation (5–8) had only minor influence on the hydrodynamic particle size. Acute toxicity of nanosivler to zebrafish (Danio rerio) was investigated in a 48-hour static renewal study and compared with the toxicity of silver ions (AgNO3). The nanosilver and silver ion 48-hour median lethal concentration (LC50) values were 84 μg L−1and 25 μg L−1, respectively. To investigate exposure-related stress, the fish behaviour was observed visually after 0, 3, 6, 12, 24, 27, 30, and 48 hours of both nanosilver and ionic silver treatments. These observations revealed increased rate of operculum movement and surface respiration after nanosilver exposure, suggesting respiratory toxicity. The present study demonstrates that silver nanoparticles are lethal to zebrafish.

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