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Nonwoven fabrics are the primary source of disposable medical clothing, which cause a huge medical waste. One possible way to reuse this disposable clothing is through antibacterial treatment. Among various metal nanoparticles, silver nanoparticles (AgNPs) are preferable regarding ecology and human health. Green synthesis is an ecological alternative to synthesize AgNPs from silver nitrate (AgNO3) solution. The silver nanoparticles (AgNPs) were successfully synthesized from Calendula arvensis extract and AgNO3 at a certain temperature and incorporated into the fabric by padding and in-situ method. The pretreatments applied to the nonwoven fabric were found very important in terms of providing antibacterial activity. AgNPs applied according to the in situ method could provide 99% antibacterial activity on nonwoven surface fabrics. The samples treated by AgNPs with the in situ method performed better for both particle filtration efficiency (PFE) and bacterial filtration efficiency (BFE) than the samples treated with the padding method. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (MNPs) have gained significant attention due to their multifunctional properties and broad applications in various fields. In this study, we present a novel and sustainable approach for the synthesis of silver nanoparticles (AgNPs) using waste materials, dried banana pith extract (BPE) and rice water. The synthesised AgNPs exhibit a size of 43 nm and zeta potential of −24.1 mV. A maximum temperature rise of 4°C with an efficiency of 41% is achieved within a short time by the photothermal activity. The qualitative colorimetric detection of Fe3+ and its quantitative spectroscopic detection are achieved in a linear detection range of 20–80 μM and with a limit of detection of 8.5 μM. The sensing mechanism is explained in terms of cooperative binding of Fe3+ ions to BPE-AgNPs. A homogeneous, flexible and stable AgNP-rice starch gel is formed. The work offers environmentally conscious nanomaterials for diverse applications. [ABSTRACT FROM AUTHOR]

The present work aims to study the possibilities of developing silver nanoparticles using natural extracts of grape pomace wastes originating from the native variety of Fetească Neagră 6 Șt. This study focused on investigating the influence of grape pomace extract obtained by two different extraction methods (classical temperature extraction and microwave-assisted extraction) in the phytosynthesis process of metal nanoparticles. The total phenolic content of the extracts was assessed using the spectrophotometric method with the Folin–Ciocâlteu reagent, while the identification and quantification of specific components were conducted through high-performance liquid chromatography with a diode array detector (HPLC-DAD). The obtained nanoparticles were characterized by UV–Vis absorption spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM), along with assessing their antioxidant and antimicrobial properties against Gram-positive bacteria. The data collected from the experiments indicated that the nanoparticles were formed in a relatively short period of time (96 h) and, for the experimental variant involving the use of a 1:1 ratio (v/v, grape pomace extract: silver nitrate) for the nanoparticle phytosynthesis, the smallest crystallite sizes (from X-ray diffraction—4.58 nm and 5.14 nm) as well as spherical or semispherical nanoparticles with the lowest average diameters were obtained (19.99–23 nm, from TEM analysis). The phytosynthesis process was shown to enhance the antioxidant properties (determined using the DPPH assay) and the antimicrobial potential (tested against Gram-positive strains) of the nanoparticles, as evidenced by comparing their properties with those of the parent extracts; at the same time, the nanoparticles exhibited a selectivity in action, being active against the Staphylococcus aureus strain while presenting no antimicrobial potential against the Enterococcus faecalis strain. [ABSTRACT FROM AUTHOR]

Nanotechnology is developing into a fast-expanding discipline with applications in science and technology, and nanostructures are a crucial research tool in many fields. Due to their remarkable electrical, optical, magnetic, catalytic, and pharmacological capabilities, metal and metal oxide nanoparticles (NPs) have drawn study interest. Natural elements (plants, microorganisms, fungi, etc.) are utilized in a chemical-free, environmentally benign way to synthesize metals and metal oxides. The optical, electrical, and antimicrobial qualities of silver nanoparticle (AgNP) make them a popular choice. More than 200 active ingredients, including water-soluble, organic-soluble, and volatile chemicals, are found in Ganoderma. The main components are polysaccharides, adenosine, and terpenoids, each of which has exceptional therapeutic properties. This article explains the synthesis of Ag NPs by Ganoderma lucidum and tests the antibacterial effectiveness for use in biological applications. [ABSTRACT FROM AUTHOR]

Antimicrobial natural polymer film with silver nanoparticles (AgNPs) biosynthesized using aqueous plant root extracts as reducing capping agents and for film formatting show extensive applicability for pathogenic microorganism problems. The formation of AgNPs was confirmed by transmission electron microscopy (TEM) and scanning electron microscopy–energy-dispersive spectroscopy (SEM–EDS) techniques. The antimicrobial activity of biofilm with green AgNPs was analysed by inhibiting the growth of Gram-negative and Gram-positive bacteria culture using the Kirby–Bauer disk diffusion susceptibility test. Total phenolic content and antioxidant activity were slightly higher in aqueous extracts of Sym. Radix than in Sym. Radix/AgNPs. The antimicrobial effect of polymer film/AgNPs against selected test bacteria cultures was substantially more robust than with pure film. Pictures of AgNPs obtained by TEM revealed the presence of spherical-shaped nano-objects with an average size 27.45 nm. SEM–EDS studies confirmed the uniform distribution of metal nanoparticles throughout the biopolymeric matrix. Morphological studies of the surface showed that the obtained surface of the films was even, without holes or other relief irregularities. These apparent Symphyti radix polymer film/AgNPs' biological functions could provide a platform for fighting pathogenic bacteria in the era of multi-drug resistance. [ABSTRACT FROM AUTHOR]

Infections caused by Staphylococcus aureus and Klebsiella pneumoniae are becoming a common health issue throughout the world. Medicines that have been used to treat infections caused by these organisms are becoming obsolete due to the emergence of drug resistance at an alarming rate. Recently, the use of green synthesized nanoparticles has been gaining momentum as an alternative approach to combating microbial infections, since traditional methods for the synthesis of metal nanoparticles involve the use of toxic chemicals and the formation of harmful by‐products. In this study, an aqueous extract of the medicinal plant Prunella vulgaris is used for the synthesis of silver oxide nanoparticles (AgONPs). The formation of AgONPs is confirmed by UV‐visible spectroscopy in the wavelength range of 200–400 nm. X‐ray analysis of AgONPs shows crystallite size of the particles to be 36.9 nm. Scanning electron microscopic image shows the synthesized AgONPs are seemed to be spherical and oval in morphology with an average size of 55–182 nm, whereas FTIR spectroscopy of AgONPs reveal the presence of functional group. Finally, AgONPs are tested to be effective against S. aureus and k. Pneumoniae. [ABSTRACT FROM AUTHOR]

The synthesis of nanoparticles using medicinal plants is a potential pathway for developing environmentally friendly drugs with minimal side effects. The aim of this study was to isolate heptadecyl-trans-p-coumarate from the medicinal plant, Artemisia afra, utilise it and its extract to synthesise silver nanoparticles (AgNPs), zinc oxide nanoparticles (ZnONPs) and iron oxide nanoparticles (Fe2O3NPs) that were evaluated for antibacterial and cytotoxic activity. AgNPs synthesised from the coumarate and extract were mostly spherical with an average size of 12 nm and 29 nm, respectively. ZnONPs were mostly rods, plates and spheres with average sizes of 31 nm (extract) and 22 nm (coumarate). Fe2O3NPs were hexagons and spheres with average sizes of 31 nm (extract) and 24 nm (coumarate). Nanoparticles improved the antibacterial activity of the extract and coumarate against Escherichia coli, Pseudomonas aeruginosa, Chromobacterium violaceum and Staphylococcus aureus. Shape of nanoparticles influenced activity; rod-shaped ZnONPs and platelet-like Fe2O3NPs synthesised using the extract exhibited better antibacterial activity. Spherical ZnONPs synthesised using the coumarate and spherical AgNPs showed greater cytotoxicity. The results suggest a synergistic effect between the metal nanoparticles and capping agents. Overall, this study confirms the use of Artemisia afra for the biosynthesis of silver, zinc oxide and iron oxide nanoparticles. [ABSTRACT FROM AUTHOR]

Green synthesis of metal nanoparticles (NPs) from plant extracts has attracted significant interest in modern medicine. therefore, this study prepared an aqueous extract of Sophora flavescens roots, which are used in folk medicine to treat several diseases, including bacterial infections. in addition, silver NPs (AgNPs) were synthesized from root extract using the green synthesis method. the NPs were diagnosed using modern methods. Additionally, the antibacterial activity of the root aqueous extract and AgNPs aqueous preparation (at concentrations of 7% and 9%, respectively) was examined against selected isolates of multidrug-resistant Pseudomonas aeruginosa and Staphylococcus aureus. the results indicated that both the plant extract and NP preparations inhibited pathogenic bacterial isolates. [ABSTRACT FROM AUTHOR]

Leucus aspera is a perennial plant traditionally used as an herbal medicine in many countries. The biosynthesis of metal nanoparticles using medicinal plants is not only economical but also environmentally friendly as well as having miscellaneous biomedical applications. In this study, Leucus aspera extract as a stabilising and reducing agent was utilised to synthesise Ag nanoparticles in the aqueous medium. In addition, the anti-alveolar cancer property of AgNPs was investigated in the in vitro condition. Various techniques containing UV–Vis. spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS) were used to characterise the synthesised nanoparticles. On the other hand, the MTT assay was run to evaluate the cytotoxicity activity of AgNPs. The crystal size of AgNPs, according to the XRD analysis, was 34.22 nm. Moreover, the uniform spherical morphology ranging from 40.67 to 58.17 nm was detected in the SEM images for the biosynthesised nanoparticles. In the antioxidant test, the IC50 of AgNPs and BHT against DPPH free radicals were 87 and 41 µg/mL, respectively. The synthesised nanocomposite had very low cell viability and high anti-alveolar cancer activities against A549 cell line without any cytotoxicity on the normal cell line (HUVEC). The viability of malignant alveolar cell line reduced dose-dependently in the presence of Ag NPs. Perhaps notable anti-alveolar cancer activities of the synthesised nanocomposite against common alveolar cancer cell line are linked to their antioxidant activities. [ABSTRACT FROM AUTHOR]

Nanomedicine is a potential provider of novel therapeutic and diagnostic routes of treatment. Considering the development of multidrug resistance in pathogenic bacteria and the commonness of cancer, novel approaches are being sought for the safe and efficient synthesis of new nanoparticles, which have multifaceted applications in medicine. Unfortunately, the chemical synthesis of nanoparticles raises justified environmental concerns. A significant problem in their widespread use is also the toxicity of compounds that maintain nanoparticle stability, which significantly limits their clinical use. An opportunity for their more extensive application is the utilization of plants, fungi, and bacteria for nanoparticle biosynthesis. Extracts from natural sources can reduce metal ions in nanoparticles and stabilize them with non-toxic extract components. [ABSTRACT FROM AUTHOR]

The development of green, low cost and sustainable synthetic routes to produce metal nanoparticles is of outmost importance, as these materials fulfill large scale applications in a number of different areas. Herein, snail slime extracted from Helix Aspersa snails was successfully employed both as bio-reducing agent of silver nitrate and as bio-stabilizer of the obtained nanoparticles. Several trials were carried out by varying temperature, the volume of snail slime and the silver nitrate concentration to find the best biogenic pathway to produce silver nanoparticles. The best results were obtained when the synthesis was performed at room temperature and neutral pH. UV–Visible Spectroscopy, SEM-TEM and FTIR were used for a detailed characterization of the nanoparticles. The obtained nanoparticles are spherical, with mean diameters measured from TEM images ranging from 15 to 30 nm and stable over time. The role of proteins and glycoproteins in the biogenic production of silver nanoparticles was elucidated. Infrared spectra clearly showed the presence of proteins all around the silver core. The macromolecular shell is also responsible of the effectiveness of the synthesized AgNPs to inhibit Gram positive and Gram negative bacterial growth. [ABSTRACT FROM AUTHOR]

The ZnO, MgO, NiO, and AlO nanoparticles and Zn–Al and Mg–Ni composite oxides were synthesized by the green method from the Prunus persica leaves extract. The synthesized nanoparticles were characterized through FT-IR, XRD, SEM, and TEM. The FT-IR study was carried out to find out the presence of various functional groups in nanoparticles. Their size was studied by the XRD method which exposed that the nanoparticles were in the range of 19–29 nm, and the size and morphology were studied by SEM, which was further confirmed by TEM. The synthesized nanoparticles were tested for antibacterial activity. In particular, ZnO showed a good inhibitory effect with 22.31 mm of inhibition against Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

The multifunctional features of noble metal nanoparticles (MNPs) were exploited in various biomedical applications, which eventually demanded the development of a sustainable green synthesis approach. In the present study, Quercetin (Q) was employed as a promising green reductant for the generation of noble metal nanoparticles such as silver (Q-AgNPs), gold (Q-AuNPs), and bimetallic (Q-Ag-AuNPs) towards biomedical perspective. Initially, the NPs were successfully synthesized in a size-controlled manner via optimizing temperature, pH, metal ion concentration, and stoichiometric ratio of the reaction mix. The redox reaction and conversion of metal ions (Ag+ and Au3+) into their respective metal nano-forms were confirmed through their surface plasmonic resonance (SPR) in UV-visible spectroscopy. In addition, different instrumentation like FT-IR, XRD, HR-TE M, and XPS analyses were performed to confirm the size, shape, and chemical composition of fabricated NPs. The bactericidal effect of fabricated NPs was tested against Gram-positive and Gram-negative pathogens. Moreover, the cytotoxic potential was screened against breast (MCF-7) and colorectal (HCT-116) carcinoma cell lines. This work revealed that the flavonoid-functionalized noble metal NPs were associated with good antibacterial and anticancer potential against selected cancer cell lines. [ABSTRACT FROM AUTHOR]

The accumulation of organic contaminants including dyes in aquatic systems is of significant environmental concern, necessitating the development of affordable and sustainable materials for the treatment/elimination of these hazardous pollutants. Here, a green synthesis strategy has been used to develop a self-assembled gum kondagogu-sodium alginate bioconjugate sponge adorned with silver nanoparticles, for the first time. The properties of the nanocomposite sponge were then analyzed using FTIR, TGA, SEM, and MicroCT. The ensued biobased sponge exhibited hierarchical microstructure, open cellular pores, good shape memory, and mechanical properties. It merges the attributes of an open cellular porous structure with metal nanoparticles and are envisaged to be deployed as a sustainable catalytic system for reducing contaminants in the aqueous environment. This nanocomposite sponge showed enhanced catalytic effectiveness (km values up to 37 min−1 g−1 and 44 min−1 g−1 for methylene blue and 4-nitrophenol, respectively), antibacterial properties, reusability, and biodegradability (65% biodegradation in 28 days). [ABSTRACT FROM AUTHOR]

Large amounts of spent coffee grounds (SCGs) are produced annually worldwide. SCGs contain high levels of phenolics and other bioactive compounds that make them a potential source of reducing and stabilizing agents for the synthesis of metal nanoparticles. This study investigates the use of SCG extracts as a green strategy to produce silver nanoparticles (AgNPs). SCG extracts were obtained using aqueous ethanol as the solvent and then contacted with a silver nitrate solution under the selected conditions. A central composite design coupled with response surface methodology was used to evaluate the effects of solvent composition (C = 30–70% v/v), silver-to-phenolic ratio (R = 3–7 mol/mol), temperature (T = 25–55 °C) and pH (10–12) on the production of AgNPs. Characterization of AgNPs by DLS, TEM and XRD techniques showed that they were highly crystalline with a narrow size distribution. Under optimal reaction conditions, AgNPs with an average size of about 10 nm and a zeta potential of −30.5 to −20.7 mV were obtained. Overall, the results of this study indicate that SCGs are a promising material for the green synthesis of small-sized and stable AgNPs. [ABSTRACT FROM AUTHOR]

In this study, we developed a novel nanocomposite by synthesizing zinc (ZnNPs), copper (CuNPs), and silver (AgNPs) nanoparticles using olive leaf extract and incorporating them into a chitosan polymer. This approach combines the biocompatibility of chitosan with the antimicrobial and anticancer properties of metal nanoparticles, enhanced by the phytochemical richness of olive leaf extract. The significance of our research lies in its potential to offer a biodegradable and stable alternative to conventional antibiotics and cancer treatments, particularly in combating multidrug-resistant bacteria and various cancer types. Comprehensive characterization through Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Transmission Electron Microscopy (TEM) confirmed the successful synthesis of the nanocomposites, with an average size of ~22.6 nm. Phytochemical analysis highlighted the antioxidant-rich composition of both the olive leaf extract and the nanoparticles themselves. Functionally, the synthesized nanoparticles exhibited potent antimicrobial activity against multidrug-resistant bacterial strains, outperforming traditional antibiotics by inhibiting key resistance genes (ermC, tetX3-q, blaZ, and Ery-msrA). In anticancer assessments, the nanoparticles showed selective cytotoxicity towards cancer cells in a concentration-dependent manner, with CuNPs and AgNPs showing particularly strong anticancer effects, while demonstrating minimal toxicity towards normal cells. ZnNPs were noted for their low cytotoxicity, highlighting the safety profile of these nanoparticles. Further, the nanoparticles induced apoptosis in cancer cells, as evidenced by the modulation of oncogenes (P21, P53, and BCL2), suggesting their therapeutic potential. The findings of our study underscore the versatile applications of these biogenic nanoparticles in developing safer and more effective antimicrobial and anticancer therapies. [Display omitted] [ABSTRACT FROM AUTHOR]

• Green synthesis of silver nanoparticles was provided using Haloxylon persicum. • Parameters affecting the reduction of silver nanoparticles were investigated. • Photocatalytic, and antibacterial activities of nanoparticles were confirmed. • Silver nanoparticles were non-toxic to human cells at bactericidal concentrations. The biological synthesis of metal nanoparticles is considered a fast, environmentally friendly and cost-effective technology. This study investigated the synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Haloxylon persicum leaf as a rangeland plant. The formation of AgNPs was examined by UV–Vis spectroscopy, X-ray diffraction, Fourier transform infrared (FTIR), energy-dispersive X-ray (EDX) spectroscopy and transmission electron microscopy (TEM). The color change of the sample from yellow to brown and the absorption peak of about 430 nm showed the synthesis of AgNPs. X-ray diffraction analysis demonstrated AgNP crystal planes with a face-centred cubic (FCC) structure at (111), (200), (220), and (311). FTIR analysis revealed that nanoparticles are coated with plant compounds and phenolic compounds; tannins and flavonoids in the extract act as reducing and stabilizing agents. EDX analysis showed a distinct peak at 3.0 kV, which indicated the successful synthesis and high purity of the AgNPs. Electron microscopy estimated the average size of synthesized AgNPs to be 10 nm. Analysis of the results of the total antioxidant capacity and free radical scavenging activity showed that the synthesized AgNPs have higher antioxidant activity than the plant extract. Also, the AgNPs indicated antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The results of this study provide the field of further development of antibacterial and antioxidant drugs using cost-effective and environmentally friendly methods. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Caralluma adscendens R.Brown var. bicolor was used for the phytosynthesis of nanomaterials. • Both nanoparticles exhibited greater pharmacological activities. • Prepared nanomaterials were characterized using FTIR, HR-TEM, EDX, and UV–Vis analysis. • Both nanoparticles showed higher wound-healing activity than CABL extract based on the MTT assay and fluorescence analysis. Nanomaterials employed in nanomedicine have the potential to function as both diagnostic and therapeutic tools for individuals. Over the past few decades, significant efforts have been made to synthesize a range of metal nanoparticles through the utilization of different plant extracts. Caralluma adscendens R. Brown var. bicolor leaves (CABL) extract was employed in this study as a reducing/capping agent for the synthesis of gold/silver nanoparticles (CABL@AgNPs/CABL@AuNPs) and explore their pharmacological properties. The successful synthesis of CABL@AgNPs and CABL@AuNPs was confirmed through the observation of surface plasmon resonance (SPR) at 439 and 522 nm using ultraviolet–visible spectrophotometer (UV–Vis). High resolution-transmission electron microscopy (HR-TEM) and energy dispersive X-ray (EDX) techniques were employed to evaluate the shape, size, and chemical composition of the as-synthesized CABL@AgNPs and CABL@AuNPs. Fourier-transform infrared spectroscopy (FTIR) was used to determine the biomolecules responsible for the reduction of metal ions and the stability of metal nanoparticles generated using plant extract. An evaluation was performed to assess the antibacterial and antifungal efficacy of the prepared aqueous CABL extract, CABL@AgNPs, and CABL@AuNPs through the implementation of the disc diffusion technique. The results demonstrated that CABL@AgNPs exhibited greater efficiency when compared to both CABL extract and CABL@AuNPs. The dose-dependent nature of antimicrobial activities was clearly demonstrated through the results of antioxidant and anti-inflammatory experiments. The wound healing activity of the prepared nanomaterials was evaluated using a variety of techniques, including MTT assay, fluorescence staining test, and in vitro scratch assay. The wound-healing capacity of prepared nanomaterials was evaluated using an in vitro scratch assay with Fibroblast L929 cells. The impact of nanoparticles at the IC 50 concentration range was analysed through a fluorescence staining experiment and MTT assay to determine toxicity levels. The environmentally friendly approach of current study shown that both nanoparticles have the potential to be effective therapeutic agents for treating different illnesses. [ABSTRACT FROM AUTHOR]

The alarming effect of antibiotic resistance prompted the search for alternative medicine to resolve the microbial resistance conflict. Over the last two decades, scientists have become increasingly interested in metallic nanoparticles to discover their new dimensions. Green nano synthesis is a rapidly expanding field of interest in nanotechnology due to its feasibility, low toxicity, eco‐friendly nature, and long‐term viability. Some plants have long been used in medicine because they contain a variety of bioactive compounds. Silver has long been known for its antibacterial properties. Silver nanoparticles have taken a special place among other metal nanoparticles. Silver nanotechnology has a big impact on medical applications like bio‐coating, novel antimicrobial agents, and drug delivery systems. This review aims to provide a comprehensive understanding of the pharmaceutical qualities of medicinal plants, as well as a convenient guideline for plant‐based silver nanoparticles and their antimicrobial activity. [ABSTRACT FROM AUTHOR]

The chemical content of plant excerpts can be efficiently employed to reduce the metal ions to nanoparticles in the one-pot green production method. Here, green production of silver nanoparticles (AC-AgNPs) is performed by means of Allium cepa var. Aggregatum (shallot) extract as a stabilizer and reducer. The shape, size, and morphology of resultant AC-AgNPs are examined by optical spectroscopy analysis such as UV for nucleation and coalescence processes of the AC-AgNPs. Through FTIR functional group is determined and through DLS size is defined, it was confirmed that metallic AgNPs were successfully synthesized through the green synthesis route, and these results agreed well with the results obtained in the XRD pattern along with TEM spectroscopy, where the TEM images confirm the formation of sphere-like nanostructures along with SAED analysis. The chemical characterization is performed with XPS; the obtained molecular species in the materials are determined from the energy profile. Antioxidant activity of AC-AgNPs versus DPPH substrate is carried out. Antibacterial activity is well established against Gram-negative and Gram-positive organisms. Cell viability is accomplished, followed by an MTT assay, and a cytotoxicity assay of AC-AgNPs on MCF—7 cell lines is also carried out. Highlights: (1). This study highlights the eco-friendly synthesis of silver nanoparticles from Allium cepa var. Aggregatum Natural Extract. (2). The synthesized AC-AgNPs were characterized by UV-VIS, FT-IR, XRD, TEM, and XPS. (3). The synthesized nanoparticles were well dispersed in nature and the size range of 35 ± 8 nm. (4). The anti-candidal activity of biosynthesized silver nanoparticles was evaluated against the following Gram-Negative organisms: Escherichia coli (E. coli), and the following Gram-positive organisms: Staphylococcus aureus strains. The biosynthesized AC-AgNPs showed enhanced antiseptic features anti both Gram-positive and negative organisms. (5). Besides, the in vitro cytotoxic outcomes of AC-AgNPs were assessed versus MCF-7 cancerous cells, and the reduction in the feasibility of cancer cells was established via MTT assay, which suggests potential biomedical applications. [ABSTRACT FROM AUTHOR]

Nanoparticles exhibiting the localized surface plasmon resonance (LSPR) phenomenon are promising tools for diagnostics and cancer treatment. Among widely used metal nanoparticles, silver nanoparticles (Ag NPs) possess the strongest light scattering and surface plasmon strength. However, the therapeutic potential of Ag NPs has until now been underestimated. Here we show targeted photothermal therapy of solid tumors with 35 nm HER2-targeted Ag NPs, which were produced by the green synthesis using an aqueous extract of Lavandula angustifolia Mill. Light irradiation tests demonstrated effective hyperthermic properties of these NPs, namely heating by 10 °C in 10 min. To mediate targeted cancer therapy, Ag NPs were conjugated to the scaffold polypeptide, affibody ZHER2:342, which recognizes a clinically relevant oncomarker HER2. The conjugation was mediated by the PEG linker to obtain Ag-PEG-HER2 nanoparticles. Flow cytometry tests showed that Ag-PEG-HER2 particles successfully bind to HER2-overexpressing cells with a specificity comparable to that of full-size anti-HER2 IgGs. A confocal microscopy study showed efficient internalization of Ag-PEG-HER2 into cells in less than 2 h of incubation. Cytotoxicity assays demonstrated effective cell death upon exposure to Ag-PEG-HER2 and irradiation, caused by the production of reactive oxygen species. Xenograft tumor therapy with Ag-PEG-HER2 particles in vivo resulted in full primary tumor regression and the prevention of metastatic spread. Thus, for the first time, we have shown that HER2-directed plasmonic Ag nanoparticles are effective sensitizers for targeted photothermal oncotherapy. [ABSTRACT FROM AUTHOR]

Green synthesis methods by plant extracts leads to production of metal nanoparticles without using harsh, toxic, and expensive chemicals commonly used in physical/chemical processes. In this study, silver nanoparticles (AgNPs) were prepared easily, fast, cost-effectively and successfully using aqueous galls extract of Quercus infectoria (Q. infectoria) as a reducing and capping agent. The results revealed that AgNPs were highly stable and their morphologies were spherical with an average diameter of about 33 nm. The galls extract and AgNPs showed excellent antibacterial activities toward four types of bacteria. The antioxidant ability of galls extract and AgNPs was evaluated by DPPH assay and showed considerable antioxidant potential. Cytotoxic activity of AgNPs was tested by MTT assay. AgNPs exhibited significant anticancer activity against human breast cancer cells (MCF-7). AgNPs synthesized by Q. infectoria galls extract with high antibacterial, antioxidant and anticancer activity would be favorable systems for bacterial disease and cancer treatment. [ABSTRACT FROM AUTHOR]

Biosynthesis of nanoparticles is the preferred route for the fabrication of biocompatible and cheaper drugs. In this study, the extract and major secondary metabolite from Helichrysum aureonitens, 3,5-dihydroxy-6,7,8-trimethoxyflavone, were used to synthesize silver and zinc oxide nanoparticles. Spectroscopic and microscopic techniques confirmed the formation of the nanoparticles. The flavone alone showed higher DPPH radical scavenging ability (IC50 = 487.1 μg mL−1) relative to the control, butylated hydroxytoluene. In addition, silver nanoparticles synthesized using the flavone had higher ferric reducing potential (Fe3+ to Fe2+) compared to the other test samples. The cytotoxic activity of the plant extract, the flavone, and their biosynthesized nanoparticles was also investigated using the MTT assay against the cancerous MCF-7 (breast adenocarcinoma) and A549 (human lung adenocarcinoma)), and non-cancerous HEK293 (human embryonic kidney) cell lines. The plant extract decreased the cell viability of A549 (IC50 = 68.6 μg mL−1) without being cytotoxic against HEK293, even at high concentrations. Silver nanoparticles significantly decreased cell viability of A549 and moderately decreased cell viability of MCF-7 but induced cell death of HEK293 even at low concentrations. This study provides a green synthesis route for silver and zinc oxide nanoparticles and confirms the therapeutic effectiveness of H. aureonitens, thereby validating its use in ethnomedicine. [ABSTRACT FROM AUTHOR]

Green synthesis of nanoparticles provides an advancement over chemical and physical methods given its cost-effectively, environment-friendly, facile, and suitability for large-scale industrial production. Due to their characteristics, silver nanoparticles are exploited in various fields such as developing electronic devices, biosensing platforms, catalysts, wastewater purification, biomedicine, antifungal, and antibacterial agent. In this study, silver nanoparticles (Ag-NPs) were synthesized using leaves extract of Biarum chaduchrum at ambient temperature, and characterized through transmission electron microscopy, particle size analyzer, and fourier transform infrared spectroscopy. The average size of synthesized Ag-NPs was estimated at 100 nm with a spherical shape. In addition, the antibacterial activity of nanoparticles against Staphylococcusaureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa was tested by minimum inhibitory concentration analysis. According to the results and observations, this procedure can be applied for large-scale synthesis of Ag-NPs and other notable metal nanoparticles with medicinal and industrial use. [ABSTRACT FROM AUTHOR]

In recent year green and eco-friendly synthesis of metal nanoparticles plays an important role in nanotechnology, medical science, industries, ceramics etc. The manuscript focuses on the green and facile synthesis of AgNPs from aqueous solution of leaf of Cassia fistula. UV-Visible spectra confirm the bio-formation of AgNPs at 412 nm with the witness of change in colour. Synthesized silver nanoparticle characterized further by FTIR, SEM, EDX and XRD spectroscopic technique. The shape of AgNPs is observed to be like oval, triangular and cylindrical respectively. EDX analysis confirmed the elemental percentage of silver 93.02%. FTIR shows shifting in bands from lower side to upside. The biosynthesized AgNPs shows antibacterial activity against E. coli and B. subtilis pathogens and it was found that AgNPs were more effective against E. coli and B. subtilis bacteria. The method used in this study for the biosynthesis of AgNPs from aqueous extracts of Cassia Fistula was green, reduce harmful chemical with no environmental hazards. [ABSTRACT FROM AUTHOR]

Eco-friendlybiosynthesis of silver nanoparticles (Ag NPs) and gold (Au NPs) nanoparticles by using Punica granatum and C. reticulata extracts were synthesized efficiently. Ag and Au NPs with sizes 8–10 nm and 30–40 nm were successfully synthesized and extracts serve as capping agents. Forming of NPs was confirmed through UV-visible spectra, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectra (FTIR) studies. The effect of NPs on the luminescence of Eu(TTFA)3 and Sm(TTFA)3 complexes was investigated. Luminescence intensities of the complexes were enhanced several times in the presence of silver and get quenched due to reabsorption of Au NPs. The nonlinear optical properties of NPs were calculated using open aperture Z-scan and degenerate four-wave mixing in the femtosecond region. The toxicity and antimicrobial activities of Ag and Au NPs were studied. [ABSTRACT FROM AUTHOR]

Plant extracts are a good alternative of reducing agents in the synthesis of metal nanoparticles. In this paper, we report the evaluation of the cytotoxic activity against T3 cell lines of the ethanolic extract of Monteverdia salicifolia (Mart ex. Reissek) Biral roots (MS) as well as a green one-pot route of synthesis of silver nanoparticles (AgNPs) using that extract as reducing and stabilizing agent. The extract exhibited dose dependent activity. The smallest particle size (48.01 nm) was achieved in just 25 minutes by employing a temperature of 65 °C and AgNO3 and MS concentrations equal to 0.9 mmol.L-1 and 0.67 mg.mL-1, respectively. The AgNPs-MS nanocomposite was characterized by UV-vis spectroscopy, FEG microscope and zeta potential, which proved that MS was effective at reducing and capping the AgNPs. In order to emphasize the advantage of the methodology applied in this synthesis, it was compared to a usual procedure using NaBH4 as a reducing agent and the greenness analysis was also carried out, using the Green Star. [ABSTRACT FROM AUTHOR]

Recently, nanotechnology has emerged as a tool for the development in the biological synthesis of noble metal nanoparticles. Among other conventional synthesis methods, biological synthesis methods have received great significance due to cost-effective and less hazardous nature which is due to the presence of plentiful as well as diversified biomolecules acting as capping and reducing agents. Biosynthesized silver nanoparticles (Ag NPs) manifest potential applications in several fields because of its safe and environment friendliness. Reported researches on the green synthesis of Ag NPs using different parts of stem, fruits, and seeds has been summarized along with the impact on the morphological properties. This review is important to find a way toward the cheaper, environmentally friendly and controlled synthesis of Ag NPs hence is of special concern. [ABSTRACT FROM AUTHOR]

[Display omitted] • Echinophora platyloba was used as source for plant extract for synthesis of AgNPs. • pH and temperature were found effective on the size of AgNPs. • Kinetic of nanoparticle growth were determined by pH of plant extract. • AgNPs showed promising performance as catalyst for degradation of complex dyes. • AgNPs showed antibacterial properties against both gram-negative and gram-positive bacetria. Green synthesis of nanomaterials for environmental application is a double win approach for environment and humanity. In this work, we present how silver nanoparticles (AgNPs) could be synthesized using Echinophora platyloba (E.P) plant extract as an environmentally friendly source, which acts as both reducing agent and capping agent for synthesis of small-sized AgNPs with maximum antibacterial and catalytic efficacy. The as-synthesized AgNPs were characterized by UV–Visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. The size of AgNPs were fine-tuned by adjusting the synthesis parameters such as pH of plant extract, temperature, and amount of AgNO 3. It was found that pH is a determining factor, where the size of AgNPs could be tuned from 15 nm to 53 nm by decreasing the pH from 10 to 7. In addition, the kinetic of growth was found pH-dependent, where small-sized AgNPs grow faster than large ones, culminating in shortening reaction time at alkaline pH. Green synthesized AgNPs (15 nm) showed remarkable catalytic performance in degradation of different individual azo dyes (i.e., Congo red (CR), Rhodamine B (Rh), methyl red (MR), bromocresol blue (BCB), Imido Black (IB)) as well as their mixture. It was found that the 90.11 % of mixture of dyes were decomposed in 8 min, following a pseudo-first order kinetic model. In addition, the antibacterial activity of the as-synthesized AgNPs (15 nm) was obtained against both gram-positive and gram-negative bacteria. The minimum inhibitory concentration (MIC) was found to be 119.06 µg/mL of silver nanoparticles for Escherichia coli (G-) and 59.53 µg/mL for Staphylococcus aureus (G +). The results of this work emphasize on how a cost-effective and green approach could be used for environmental application and affect circular economy by its potential future applications in medical and environmental fields. [ABSTRACT FROM AUTHOR]

The wide use of metal nanoparticles has raised the concern of their release in the environment and their biological safety. The use of silver nanoparticles (Ag NPs) as effective antimicrobial agent is also questioned due to the resistance developed by pathogens and the biosafety for the host. The genotoxicity caused by such particles need to be assessed to ensure that they are safe to use. In this study, green synthesized Ag NPs were used and the biosafety in terms of genotoxicity was evaluated by in vitro Chromosome aberration (CA) assay using short-term cultures of human peripheral blood. The physicochemical parameters of these Ag NPs were studied for stability in nano form. The transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) were carried out. The dynamic light scattering and zeta potential measurements revealed stable nano particles. The UV visible & fluorescence spectroscopy for binding affinity of Ag NPs did not suggest significant DNA interaction. The exposure of whole blood cultures to Ag NPs for 24 h showed dose dependent increase in frequency of CA per cell at 350, 650 and 1000 µL (P = NS, P < 0.05 and P < 0.001 respectively). Our study demonstrates that genotoxicity of Ag NPs can be reduced by the use of green synthesized Ag NPs at low dose exposure, which will guide selecting right concentrations of NP for further in vivo studies, and future applications. [ABSTRACT FROM AUTHOR]

The green approachable of metal nanoparticles is treated to be an eco-friendly path and cost-effectiveness. In this present study, nano copper was synthesized profitably by Cissus vitiginea. The synthesized nano copper was used to evaluate the antioxidant and antibacterial activity against urinary tract infections pathogens. The resulting constructed nanoparticles were characterized by using ultraviolet spectroscopy absorbance around 370 nm. Scanning electron microscopy results showed the distribution of nanoparticles and particles sizes are found to be in the range of 5–20 nm. X-ray diffraction spectrum characteristic diffraction peaks for copper nanoparticles were observed at 2θ ranges 35.5 and 43.2° correspond to lattice planes (1 1 1) and (2 0 2), respectively. X-ray photoelectron spectroscopy shows that two distinct peaks at binding energy resulted that the chemical states of copper. The results serve the evidence that the green mediated nano copper might indeed be the potential source to treat urinary tract infections caused by E. coli, Enterococcus sp., Proteus sp. and Klebsiella sp. This fact-finding conclusion is that C. vitiginea leaf extract based green synthesis nano copper particles proved to effectively kill it or significantly inhibit activity contra to urinary tract infection pathogens and exhibit excellent antioxidant activity. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have gained attention due to their exceptional physicochemical properties and biological activities, owing to which they are extensively used in biomedical field. We synthesized AgNPs by rapid microwave-assisted method using fucoidan as a reducing agent. The synthesized fucoidan-AgNPs (F-AgNPs) were characterized for the structural and functional properties. The bactericidal effect and mode of action of F-AgNPs on the pathogenic bacteria and biofilm formation were investigated along with the cytotoxicity studies. The UV–Visible spectra of the F-AgNPs showed the surface resonance peak at 419 nm. The nanoparticles were spherical in shape with particle size of 59.5 ± 1.46 nm and polydispersity index (PDI) of 0.3 ± 0.01. Capping of fucoidan on AgNPs was confirmed by FTIR with characteristic peaks of sulfate group. Silver content of F-AgNPs was 87% with 13% contribution from the fucoidan moieties. The F-AgNPs showed antimicrobial activity against common pathogenic bacteria and was able to inhibit biofilm formation in Pseudomonas aeruginosa at 20 μg/mL concentration. The oxidative stress and intracellular protein leakage were observed due to the F-AgNP interaction with the cell bringing about bactericidal effect. The results highlight the synthesis and bioactivity of AgNPs doped with organic moieties for applications as antimicrobials. [ABSTRACT FROM AUTHOR]

Different plant extracts have been utilized for biological synthesis of metal nanoparticles. However, no published literature compares the antimicrobial potential of silver nanoparticles (AgNPs) derived from extracts of mature fruit juice (SLF-AgNPs) versus callus (SLC-AgNPs) tissue of same plant. These SLF- and SLC-AgNPs exhibited variable physical and biological properties. Distinct UV-Vis absorption peak (at 250 nm) for SLF-AgNPs indicated formation of small-sized monodisperse particles. Both SLF-AgNPs (5 to 35 nm) and SLC-AgNPs (3 to 270 nm) exhibited quasi-spherical shapes. The FT-IR spectra showed occurrence of shared peaks at 3335, 1647, and 1080 cm−1 while SLC specific peaks at 1065, 1042 and 1017 cm−1. The SLF-AgNPs possessed higher DPPH free radical scavenging potential. These nanoparticles also showed better antibacterial and antimycotic action epitomized as higher inhibition zone diameters compared to SLC-AgNPs. This work can be furthered to identify predominant mechanism for improved antimicrobial potential of the synthesized AgNPs. [ABSTRACT FROM AUTHOR]

The present study investigated the possible influence of enzymatic browning of banana peel over the production of silver nanoparticles (AgNPs). Firstly, aqueous extracts of banana peel were prepared at different times after peeling and they were used as reducing and stabilizing agents for the production of AgNPs as monitored by visual inspection and spectrophotometry. Hydrodynamic diameters, polydispersity indexes, and Zeta potentials of the produced AgNPs were evaluated. Besides, antimicrobial activities of the AgNPs produced in the moment of peeling and after up to 2 h were assessed. As longer the period of time passed after peeling, AgNPs produced showed a tendency to decrease the size, to become with Zeta potential more negative, and to stabilize their polydispersity indexes. Antimicrobial assays showed that the two tested AgNPs were similarly effective against Escherichia coli and Staphylococcus aureus at 128 and 256 μM, respectively. This study demonstrated that banana peels extracts obtained after different times affected the production of AgNPs in different manners, producing AgNPs with distinct characteristics, such as hydrodynamic diameter, Zeta potential, and polydispersity index. Moreover, all tested AgNPs showed antimicrobial activity. [ABSTRACT FROM AUTHOR]

Nanobiotechnology is a fast developing scientific field having several applications in biochemistry, medicine, biology, engineering, etc. and plays a key role in the development and improvement of clean, eco-friendly, non-toxic and cost effective techniques for the synthesis and assembly of metal nanoparticles. One of the foremost green synthesis approaches includes biofabrication of silver nanoparticles (AgNPs) using plants and plant products. In the present study, we have synthesized silver nanoparticles using aqueous extract of Indian spice Asafoetida. Their formation was confirmed through UV–Vis spectral peak at 426.4 nm and their stability was also monitored for 3 months at room temperature using dynamic light scattering (DLS). DLS analysis revealed that the particles so formed were not only monodispersed in nature but also stable at room temperature for 3 months with a reported size of 90–95 nm. The characterization techniques revealed that synthesized AgNPs were well distributed with size ranging from 90 to 100 nm. Furthermore, Asafoetida-AgNPs were tested for their anticancer activity against the HepG2 cell line. Cell viability assay was done to check the percentage of viable cells and morphological changes at various test concentrations (0.01, 0.1, 1 and 10 ppm) after 24 and 48 h of exposure. The recorded viable cells at lowest concentration (0.01 ppm) was found to be 58.55% and at highest concentration (10 ppm) it was 40.08% after 24 h. Further, when the percent cell viability was observed at 48 h it was 45.22% and 20.23% at lowest and highest concentrations. Morphological characterization of HepG2 cells after the treatment of Asafoetida-AgNPs showed floating and patchy cells signifying their toxic nature against cancerous cells. [ABSTRACT FROM AUTHOR]

This research reports the fabrication of silver, gold and gold‐silver bimetallic nanoparticles (NPs) using aqueous extracts of green marine alga Ulva reticulata. Analysis by UV‐Vis spectrometry, X‐ray diffraction, energy dispersive X‐ray spectroscopy, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy confirmed the biosynthesis of NPs by the seaweed extract. Surface plasmon resonances (SPR) were recorded at 439, 539 and 528 nm for silver (AgNPs), gold (AuNPs) and bimetal (Au core‐Ag shell) NPs, respectively. AgNPs and AuNPs were mostly spherical in shape with size range of 7 to 36 and 19 to 32 nm, respectively, whereas Au−Ag NPs showed core‐shell formation with star like structure shaped nanoparticles with size range of 57 to 230 nm. The results confirmed that Au ions reduced faster than Ag and the resultant bimetallic nanoparticles arrangement were found to be Au core and Ag shell. Chemical constituents such as ulvan and other polysaccharides of the green seaweed extract were identified as reducing and stabilizing agents for nanoparticles formation. [ABSTRACT FROM AUTHOR]

In the storyline of metal nanoparticles, green synthesis is emerging at a very fast pace. In this experimentation phenomena, nanoparticles of Titanium dioxide were coalesced using an extract solution of oscimum sanctum herba as a bioreductant. This is novel and interesting method for synthesis of TiO2 nanoparticles. The prepared titanium dioxide nanoparticles were distinguished using ultraviolet-visible spectroscopy (UV-VIS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM). The girth range of TiO2 nanoparticles was evaluated to be in the range of 90-100 nm. Moreover, the reaction which was alkaline by behavior of the solution (pH = 8) resulted in the increase in absorbance (at 570 nm and 490 nm), which sparges the growth of the number of TiO2 nanoparticles in the studied solution. The microscopic technique showed that the diameter of TiO2 was in the range of 6-10 nm but with little agglomeration. Also, its Antibiofilm activity was accessed with correlation to optical densities, biofilm formation capability of microbes make their distortion tedious but fighting strategy of nanoparticles could be a revolution in antibacterial investigations 450 µg/l of nanoparticles from both the extracts targeted the biofilms of E.coli. [ABSTRACT FROM AUTHOR]

Increasing antimicrobial resistance is a clinical crisis worldwide. Recent progress in the field of green synthesis has fascinated scientists and researchers to explore its potentials against pathogenic microbes. Bioinspired-metal-based nanoparticles (silver, copper, gold, zinc, etc.) have been reported to be tested against both Gram-positive and Gram-negative bacteria such as B. subtilis, E. coli, Staphylococcus aureus, etc., as well as some pathogenic fungi including A. niger, F. oxysporum, A. fumigatus, etc., and are testified to exhibit inhibitory effects against pathogenic microbes. The possible modes of action of these metal nanoparticles include: (a) excess production of reactive oxygen species inside microbes; (b) disruption of vital enzymes in respiratory chain via damaging microbial plasma membranes; (c) accumulation of metal ions in microbial membranes; (d) electrostatic attraction between metal nanoparticles and microbial cells which disrupt metabolic activities; and (e) inhibition of microbial proteins/enzymes by increased production of H2O2. Although these pathways are interconnected, information on potential mechanism of most of these biogenic nanoparticles is still limited. Further exploration of these mechanisms could help in tackling the burning issue of antibiotics resistance. [ABSTRACT FROM AUTHOR]

The exploitation of various plant materials for the synthesis of nanoparticles is considered as a green technology as it does not necessitate any hazardous chemicals. Here we report the synthesis of silver and gold nanoparticles using an aqueous rhizome extract of a medicinal plant, Costus speciosus by microwave assisted method. The silver and gold nanoparticles show high antimicrobial activities against both bacterial and fungal strains. Also, the nanoparticles exhibit high radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, the nanoparticles show excellent catalytic activity in the reduction of 4-nitrophenol and methylene blue in the presence of sodium borohydride (NaBH4). [ABSTRACT FROM AUTHOR]

The metal nanoparticles, due to interesting features such as electrical, optical, chemical and magnetic properties, have been investigated repeatedly. Also, the mentioned nanoparticles have specific uses in terms of their antibacterial activity. The biosynthesis method is more appropriate than the chemical method for producing the nanoparticles because it does not need any special facilities; it is also economically affordable. In the current study, the silver nanoparticles (AgNPs) were obtained by using a very simple and low‐cost method via Glaucium corniculatum (L.) Curtis plant extract. The characteristics of the AgNPs were investigated using techniques including: X‐ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy. The SEM and TEM images showed that the nanoparticles had a spherical shape, and the mean diameter of them was 53.7 and 45 nm, respectively. The results of the disc diffusion test used for measuring the anti‐bacterial activity of the synthesised nanoparticles indicated that the formed nanoparticles possessed a suitable anti‐bacterial activity. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were successfully synthesized from the reduction of Ag+ using AgNO3 solution as a precursor and Brassica rapa var. japonica leaf extract as a reducing and capping agent. This study was aimed at synthesis of AgNPs, exhibiting less toxicity with high antibacterial activity. The characterization of AgNPs was carried out using UV-Vis spectrometry, energy dispersive X-ray spectrometry, fourier transform infrared spectrometry, field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and transmission electron microscopy analyses. The analyses data revealed the successful synthesis of nano-crystalline Ag possessing more stability than commercial AgNPs. The cytotoxicity of Brassica AgNPs was compared with commercial AgNPs using in vitro PC12 cell model. Commercial AgNPs reduced cell viability to 23% (control 97%) and increased lactate dehydrogenase activity at a concentration of 3 ppm, whereas, Brassica AgNPs did not show any effects on both of the cytotoxicity parameters up to a concentration level of 10 ppm in PC12 cells. Moreover, Brassica AgNPs exhibited antibacterial activity in terms of zone of inhibition against E. coli (11.1 ± 0.5 mm) and Enterobacter sp. (15 ± 0.5 mm) which was higher than some previously reported green-synthesised AgNPs. Thus, this finding can be a matter of interest for the production and safe use of green-AgNPs in consumer products. [ABSTRACT FROM AUTHOR]

Nanotechnology has emerged as a prominent scientific discipline in the technological revolution of this millennium. The scientific community has focused on the green synthesis of metal nanoparticles as compared to physical and chemical methods due to its eco-friendly nature and high efficacy. Medicinal plants have been proven as the paramount source of various phytochemicals that can be used for the biogenic synthesis of colloidal silver and gold nanoparticles as compared to other living organisms, e.g., microbes and fungi. According to various scientific reports, the biogenic nanoparticles have shown promising potential as wound healing agents. However, not a single broad review article was present that demonstrates the wound healing application of biogenic silver and gold nanoparticles. Foreseeing the overall literature published, we for the first time intended to discuss the current trends in wound healing via biogenic silver and gold nanoparticles. Furthermore, light has been shed on the mechanistic aspects of wound healing along with futuristic discussion on the faith of biogenic silver and gold nanoparticles as potential wound healing agents. [ABSTRACT FROM AUTHOR]

Abstract: Green synthesis of silver nanoparticles-calcium alginate beads (AgNP-CA) was prepared using five different methods. The immobilization/reduction/incorporation of AgNPs on alginate biopolymer using Walsura trifoliata bark extract as reducing and capping agent were confirmed by the characterization results of UV-Vis spectra, XRD, FTIR, and TEM techniques. The prepared Ag-CA nanocomposite catalyst was used for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4) in a liquid phase at ambient conditions. Comparatively, AgNPs-ACA (Adsorption calcium alginate) exhibited very high catalytic activity in the reduction of 4-nitrophenol within few seconds with exceptional stability, up to ten cycles without any loss in the catalytic activity. This study reports effective synthesis of AgNPs on alginate polymer beads via phytochemicals of aqueous extract of W. trifoliata and its excellent catalytic efficiency towards 4-nitrophenol reduction as of the practical application.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Green synthesis of metal nanoparticles using earth abundant materials in the absence of any toxic solvent, reducing agent and protecting group is one of the emerging areas of research in materials chemistry. Herein, we report a green method for the synthesis of silver nanoparticles (AgNPs) using Actinodaphne madraspatana Bedd leaf extract as reducing as well as stabilizing agent. To our delight, AgNPs of different sizes could be readily synthesized by simply changing the pH of plant extract and the average size of AgNPs were found to be 60, 35 and 20 nm at pH 6, 9 and 12 respectively. The efficacy of prepared AgNPs towards the catalytic reduction of 4-nitrophenol (4-NP) has been investigated and the nanocatalysts have demonstrated excellent catalytic activity as evidenced from the rate constants. The kinetics of reduction reaction follows Langmuir-Hinshelwood mechanism, based on which the rate constant ' k' was calculated. The effect of catalyst dosage, concentration of 4-NP, concentration of NaBH and size of AgNPs towards catalytic reduction of 4-NP has been systematically investigated. It was interesting to notice that the AgNPs have exhibited size dependent catalytic activity towards reduction of 4-NP and the catalytic activity was found to increase with decrease in particle size. Graphical Abstract: [ABSTRACT FROM AUTHOR]

In this research Kelussia odoratissima Mozaff. leaf extract was used for the green synthesis of silver nanoparticles (AgNPs). At first we compared antioxidant activity of different extracts of K. odoratissima. Then solution containing silver nitrate was treated with the extract which showed high antioxidant activity. Synthesized AgNPs were evaluated by analyzing the excitation of surface plasmon resonance. TEM analysis was also used for nanoparticle characterization. Antibacterial activity of the solution containing AgNPs was measured by microdilution test. Common food contaminant bacteria such as gram-positive (Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes) and gram-negative (Escherichia coli O157: H7, Salmonella enterica and Pseudomonas aeruginosa) were used for the evaluation. The aqueous extract showed the highest antioxidant activity and the solution was used for the green synthesis of AgNPs. The particle diameters were calculated to be 20-40nm with -17 to -19.9 mV zeta potential. The TEM micrographs showed that the AgNPs are nearly spherical in shape and highly monodispersed. MIC of the AgNPs against gram-positive and gram-negative bacteria was between 0.012-0.025 and 0.006-0.012 mg/ml respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag NPs were prepared using Syzygium cumini fruit extract by green method. • The developed Ag NPs having a size of ∼47 nm and nearly spherical. • Ag NPs exhibited antibacterial properties against various gram-positive and gram-negative bacterial strains. • Ag NPs found to have potent anti-inflammatory and antioxidant activity. The biosynthesis of silver nanoparticles have received great attention in the field of nanotechnology because of its antimicrobial and biomedical applications. In the current research scenario, the green synthesis of metal nanoparticles is expected to be cost-effective and environmentally benign alternative. In this effort, the fruit extracts from the Syzygium cumini was used as the reducing agent to synthesize silver nanoparticles (AgNPs) and the antioxidant, antibacterial, and anti-inflammatory properties of the synthesized nanoparticles have been evaluated. The synthesized Ag nanoparticles were characterized by UV–Visible spectroscopy (UV), Fourier-transform infrared spectroscopy (FTIR), Powder X-ray Diffraction (XRD) and scanning electron microscope (SEM).The formation of silver nanoparticles was confirmed by optical performance i.e change in color using UV–Visible spectroscopy showing a characteristic peak of silver nanoparticles at 443 nm. The presence of OH and C=O of plant secondary metabolites of Syzygium cumini were confirmed by FTIR spectroscopy, liable for capping and reduction of metal nanoparticles surface. Powder XRD analysis was used to analyze the crystal structure. This medicinal plant extract mediating green biosynthesized silver nanoparticles exhibited good in vitro- antioxidant, antibacterial and anti-inflammatory activities. Therefore, results of the present study highlights the synthesis of cost-effective, eco-friendly drugs with less side effects, which showed that there is the urge of in vivo studies at a molecular level to develop silver nanoparticles through greener approach using the medicinal plant (Syzygium cumini) extract as antibacterial, antioxidant, and anti-inflammatory agent for the treatment of bacterial infection, inflammation and many free radical oriented diseases. [ABSTRACT FROM AUTHOR]

The demand for the green synthesis of nanoparticles has gained prominence over the conventional chemical and physical syntheses, which often entails toxic chemicals, energy consumption and ultimately lead to negative environmental impact. In the green synthesis approach, naturally available bio-compounds found in plants and fungi can be effective and have been proven to be alternative reducing agents. Fungi or mushrooms are particularly interesting due to their high content of bioactive compounds, which can serve as excellent reducing agents in the synthesis of nanoparticles. Apart from the economic and environmental benefits, such as ease of availability, low synthesis/production cost, safe and no toxicity, the nanoparticles synthesized from this green method have unique physical and chemical properties. Stabilisation of the nanoparticles in an aqueous solution is exceedingly high, even after prolonged storage with unperturbed size uniformity. Biological properties were significantly improved with higher biocompatibility, anti-microbial, anti-oxidant and anti-cancer properties. These remarkable properties allow further exploration in their applications both in the medical and agricultural fields. This review aims to explore the mushroom-mediated biosynthesis of nanomaterials, specifically the mechanism and bio-compounds involved in the synthesis and their interactions for the stabilisation of nanoparticles. Various metal and non-metal nanoparticles have been discussed along with their synthesis techniques and parameters, making them ideal for specific industrial, agricultural, and medical applications. Only recent developments have been explored in this review. [Display omitted] • A detailed mechanism contributing to the mycogenic synthesis of NPs has been described. • Demonstrates the role of different mushroom species to different sizes, shapes, stability and homogeneity of NPs. • Provides ideal physical and chemical properties of the mycogenic synthesized NPs. • Illustrates properties as well as unique applications arising from species-specific NPs. • Explores wider applications extending to biomedical, environmental and industrial sectors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reliable green synthesis of silver nanoparticles (AgNPs) by cashew nutshells. [•] Green synthesis of AgNPs by cashew nutshells. [•] Higher temperatures speed up the synthesis of AgNPs by cashew nutshells. [•] Size-controlled synthesis of AgNPs by cashew nutshells. [•] Antifungal activity of AgNPs greenly synthesized by cashew nutshells. [ABSTRACT FROM AUTHOR]

Green synthesis of metal nanoparticles has been gaining great interest due to the increasing need for eco-friendly manufacturing and application of nanomaterials. Metal nanoparticles, especially silver nanoparticles, are widely used in water treatments and as environmental remedy. Here we present a method to synthesize silver nanoparticles at room temperature using green tea extract under visible light irradiation, along with an application for enhanced photocatalytic degradation on methylene blue (MB) dye. Ag nanoparticles were synthesized under different photoreduction times and then further characterized. The photocatalytic rate of synthesized nanoparticles was also investigated and compared with TiO2 nanowires under UV and visible light irradiations. The results showed that Ag nanoparticles can directly degrade MB dye through plasmonic excitation and electron transferring under visible light, and Ag nanoparticles can further enhance TiO2 photonic degradation by enhanced e-h separation with UV and/or a wide band light, including UV light. Ag nanoparticles under visible light photoreduction for 0.5 h presented better behavior for two kinds of plasmonic enhanced photodegradation; the average size of the nanoparticles is about 30 nm. Therefore, the green synthesized Ag nanoparticles exhibit promising prospects in chemical and biological pollutant treatment. [ABSTRACT FROM AUTHOR]

Nanoscience enables researchers to develop new and cost-effective nanomaterials for energy, healthcare, and medical applications. Silver nanoparticles (Ag NPs) are currently increasingly synthesized for their superior physicochemical and electronic properties. Good knowledge of these characteristics allows the development of applications in all sensitive and essential fields in the service of humans and the environment. This review aims to summarize the Ag NPs synthesis methods, properties, applications, and future challenges. Generally, Ag NPs can be synthesized using physical, chemical, and biological routes. Due to the great and increasing demand for metal and metal oxide nanoparticles, researchers have invented a new, environmentally friendly, inexpensive synthetic method that replaces other methods with many defects. Studies of Ag NPs have increased after clear and substantial support from governments to develop nanotechnology. Ag NPs are the most widely due to their various potent properties. Thus, this comprehensive review discusses the different synthesis procedures and electronic applications of Ag NPs. [ABSTRACT FROM AUTHOR]