Role of Ribes khorassanicum in the biosynthesis of AgNPs and their antibacterial properties

Silver nanoparticles (AgNPs) have been biosynthesised through the extracts of Ribes khorassanicum fruits, which served as the reducing agents and capping agents. Biosynthesised AgNPs have been found to be ultraviolet–visible (UV–vis) absorption spectra since they have displayed one surface plasmon resonance peak at 438 nm, attesting the formation of spherical NPs. These particles have been characterised by UV–vis, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy analysis. The formation of AgNPs at 1.0 mM concentration of AgNO₃ has resulted in NPs that contained mean diameters in a range of 20–40 nm. The green‐synthesised AgNPs have demonstrated high antibacterial effect against pathogenic bacteria (i.e. Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa). Biosynthesising metal NPs through plant extracts can serve as the facile and eco‐friendly alternative for chemical and/or physical methods that are utilised for large‐scale nanometal fabrication in various medical and industrial applications.Inspec keywords: X‐ray diffraction, X‐ray chemical analysis, nanofabrication, surface plasmon resonance, nanoparticles, antibacterial activity, microorganisms, scanning electron microscopy, silver, nanomedicine, visible spectra, ultraviolet spectra, transmission electron microscopy, Fourier transform infrared spectra, field emission scanning electron microscopy, biomedical materialsOther keywords: antibacterial properties, silver nanoparticles, reducing agents, capping agents, surface plasmon resonance peak, spherical NPs, field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, transmission electron microscopy analysis, plant extracts, ultraviolet‐visible absorption spectra, Fourier transform infrared spectroscopy, antibacterial effect, Ribes khorassanicum fruits, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, surface plasmon resonance, AgNO₃ , Ag     

Synthesis and characterisation of silver nanoparticles using leaf extract of Artemisia afra and their in vitro antimicrobial and antioxidant activities

In this study, the conversion of silver ions into ∼30.74 nm sized silver nanoparticles (AgNPs) was achieved in 30 min at a reaction temperature of 80–90°C in aqueous leaf extract of Artemisia afra. The synthesised AgNPs showed surface plasmon resonance in the range of 423–438 nm. Spherical and face‐centred cubic nanoparticles were confirmed by transmission electron microscope (TEM) and X‐ray diffraction (XRD) analysis, respectively. Fourier transform infra‐red (FTIR) results indicated that the obtained nanoparticles were stabilised and capped through the carbonyl and carboxylate ion groups possibly from flavonoids, terpenoids, phenolics and esters content of the extracts. In addition, the AgNPs were assessed for their biological potentials against some microbes and, also, their free radical scavenging ability was established. The AgNPs exhibited interesting antimicrobial and antioxidant properties better than the aqueous extract of A. afra. Inspec keywords: silver, transmission electron microscopy, ultraviolet spectra, visible spectra, surface plasmon resonance, antibacterial activity, X‐ray diffraction, microorganisms, nanoparticles, nanofabrication, Fourier transform infrared spectraOther keywords: silver nanoparticles, reaction temperature, surface plasmon resonance, face‐centred cubic nanoparticles, antioxidant properties, silver ion conversion, aqueous leaf extract, carboxylate ion group, antimicrobial properties, Artemisia afra, spherical nanoparticles, TEM, XRD, FTIR spectra, Ag, temperature 80 degC to 90 degC, time 30.0 min, free radical scavenging, esters, phenolics, terpenoids, flavonoids, carbonyl ion group     

Diospyros assimilis root extract assisted biosynthesised silver nanoparticles and their evaluation of antimicrobial activity

The current research study focuses on biosynthesis of silver nanoparticles (Ag NPs) for the first time from silver acetate employing methanolic root extract of Diospyros assimilis. The UV–Vis absorption spectrum of biologically synthesised nanoparticles displayed a surface plasmon peak at 428 nm indicating the formation of Ag NPs. The influence of metal ion concentration, reaction time and amount of root extract in forming Ag NPs by microscopic and spectral analysis was thoroughly investigated. Structural analysis from transmission electron microscopy confirmed the nature of metallic silver as face‐centered cubic (FCC) crystalline with an average diameter of 17 nm, which correlates with an average crystallite size (19 nm) calculated from X‐ray diffraction analysis. Further, the work was extended for the preliminary examination of antimicrobial activity of biologically synthesised Ag NPs that displayed promising activity against all the tested pathogenic strains.Inspec keywords: antibacterial activity, nanoparticles, silver, particle size, nanofabrication, nanomedicine, biomedical materials, ultraviolet spectra, visible spectra, optical microscopy, surface plasmon resonance, transmission electron microscopy, crystallites, X‐ray diffraction, microorganismsOther keywords: Diospyros assimilis root extract assisted biosynthesised silver nanoparticles, antimicrobial activity, silver acetate, methanolic root extract, UV‐visible absorption spectrum, biologically synthesised nanoparticles, surface plasmon peak, Ag NPs formation, metal ion concentration, reaction time, microscopic analysis, spectral analysis, structural analysis, transmission electron microscopy, metallic silver, FCC crystalline phase, average crystallite size, X‐ray diffraction analysis, pathogenic strains, Ag     

Biogenic synthesis,optimisation and antibacterial efficacy of extracellular silver nanoparticles using novel fungal isolate Aspergillus fumigatus MA

To eliminate the elaborate processes employed in other non‐biological‐based protocols and low cost production of silver nanoparticles (AgNPs), this study reports biogenic synthesis of AgNPs using silver salt precursor with aqueous extract of Aspergillus fumigates MA. Influence of silver precursor concentrations, concentration ratio of fungal extract and silver nitrate, contact time, reaction temperature and pH are evaluated to find their effects on AgNPs synthesis. Ultraviolet–visible spectra gave surface plasmon resonance at 420 nm for AgNPs. Fourier transform infrared spectroscopy and X‐ray diffraction techniques further confirmed the synthesis and crystalline nature of AgNPs, respectively. Transmission electron microscopy observed spherical shapes of synthesised AgNPs within the range of 3–20 nm. The AgNPs showed potent antimicrobial efficacy against various bacterial strains. Thus, the results of the current study indicate that optimisation process plays a pivotal role in the AgNPs synthesis and biogenic synthesised AgNPs might be used against bacterial pathogens; however, it necessitates clinical studies to find out their potential as antibacterial agents.Inspec keywords: nanoparticles, microorganisms, cellular biophysics, silver, antibacterial activity, pH, surface plasmon resonance, ultraviolet spectra, visible spectra, X‐ray diffraction, Fourier transform infrared spectra, optimisation, nanomedicine, nanofabricationOther keywords: biogenic synthesis, optimisation, antibacterial efficacy, extracellular silver nanoparticles, fungal isolate Aspergillus fumigatus MA, nonbiological‐based protocols, silver salt precursor, fungal extract, silver nitrate, pH, ultraviolet‐visible spectra, surface plasmon resonance, Fourier transform infrared spectroscopy, X‐ray diffraction, crystalline nature, transmission electron microscopy, spherical shapes, potent antimicrobial efficacy, bacterial strains, optimisation process, bacterial pathogens, antibacterial agents, wavelength 420 nm, size 3 nm to 20 nm, Ag     

Facile synthesis of silver nanoparticles mediated by polyacrylamide‐reduction approach to antibacterial application

The current time increase in the prevalence of antibiotic resistant ‘super‐bugs’ and the risks associated with food safety have become global issues. Therefore, further research is warranted to identify new and effective antimicrobial substances. Silver nanoparticles (Ag‐NPs) were synthesized by autoclaving technique using, different concentrations of Ag salt (AgNO₃) solution (1, 5, 10, and 25 mM). Their presence was confirmed by a surface plasmon resonance band at ∼435 nm using UV–Vis absorption spectra. The morphology of the synthesized Ag‐NPs stabilized by polyacrylamide (PAM) was examined by TEM, SAED, and EDS. TEM images revealed that the synthesized Ag‐NPs had an average diameter of 2.98±0.08 nm and SAED and EDS results confirmed the formation of Ag‐NPs. In addition, FT‐IR spectroscopy revealed that a PAM polymer matrix stabilized the Ag‐NPs. The well diffusion method, was used to test, Gram positive and Gram negative bacteria were examined. Also the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were studied against Ag‐NPs. The Ag‐NPs exhibited strong inhibitory activity, MIC and MBC against the tested clinical bacterial isolates. These results suggest that Ag‐NPs stabilized in PAM are highly effective against clinical bacterial isolates can be applied in medical fields.Inspec keywords: antibacterial activity, silver, nanoparticles, nanomedicine, surface plasmon resonance, X‐ray chemical analysis, transmission electron microscopy, electron diffraction, Fourier transform infrared spectroscopy, microorganisms, ultraviolet spectra, visible spectraOther keywords: Ag‐NP facile synthesis, PAM‐reduction approach, antibacterial application, antibiotic resistant super‐bugs, food safety, antimicrobial agents, antibiotics, antimicrobial substances, Ag salt solution concentration, ultraviolet‐visible absorption spectra, polyacrylamide, transmission electron microscopy, electron diffraction, energy dispersive X‐ray spectroscopy, TEM images, Fourier transform infrared spectroscopy, PAM polymer matrix, diffusion method, Gram positive bacteria, Gram negative bacteria, clinical bacterial isolates, Ag     

Evaluation of antimicrobial activity of synthesised silver nanoparticles using Thymus kotschyanus aqueous extract

Development of a green chemistry process for the synthesis of silver nanoparticles (AgNPs) has become a focus of interest. Characteristics of AgNPs were determined using techniques, such as ultraviolet–visible spectroscopy (UV–vis), Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy and X‐ray diffraction (XRD). The synthesised AgNPs using Thymus kotschyanus had the most growth inhibition against gram‐positive bacteria such as Staphylococcus aureus and Bacillus subtilise, while the growth inhibition of AgNPs at 1000–500 µg/ml occurred against Klebsiella pneumonia and at 1000–250 µg/ml of AgNPs was observed against E. coli. The UV–vis absorption spectra confirmed the formation of the AgNPs with the characteristic peak at 415 nm and SEM micrograph acknowledged spherical particles in a nanosize range. FTIR measured the possible biomolecules that are responsible for stabilisation of AgNPs. XRD analysis exhibited the crystalline nature of AgNPs and showed face‐centred cubic structure. The synthesised AgNPs revealed significant antibacterial activity against gram‐positive bacteria.Inspec keywords: visible spectra, microorganisms, ultraviolet spectra, biomedical materials, nanofabrication, nanoparticles, X‐ray diffraction, scanning electron microscopy, molecular biophysics, X‐ray chemical analysis, nanomedicine, silver, antibacterial activity, Fourier transform infrared spectraOther keywords: green chemistry process, ultraviolet–visible spectroscopy, gram‐positive bacteria, silver nanoparticles, Thymus kotschyanus aqueous extract, UV–vis spectroscopy, Fourier transform infrared spectroscopy, FTIR analysis, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, SEM micrograph, X‐ray diffraction, XRD, Staphylococcus aureus, Bacillus subtilise, Klebsiella pneumonia, E. coli, UV–vis absorption spectra, face‐centred cubic structure, antibacterial activity, antimicrobial activity, wavelength 415.0 nm, Ag     

Fabrication and characterisation of silver nanoparticles using bract extract of Musa paradisiaca for its synergistic combating effect on phytopathogens,free radical scavenging activity,and catalytic efficiency

This work explores the rapid synthesis of silver nanoparticles (AgNPs) from Musa paradisiaca (M. paradisiaca) bract extract. The bio‐reduction of Ag⁺ ion was recorded using ultraviolet–visible spectroscopy by a surface plasmon resonance extinction peak with an absorbance at 420 nm. The phytoconstituents responsible for the reduction of AgNPs was probed using Fourier transform infrared spectroscopy. The X‐ray diffraction pattern confirmed the formation of crystalline AgNPs that were analogous to selected area electron diffraction patterns. Morphological studies showed that the obtained AgNPs were monodispersed with an average size of 15 nm. The biologically synthesised AgNPs showed higher obstruction against tested phytopathogens. The synthesised AgNPs exhibited higher inhibitory zone against fungal pathogen Alternaria alternata and bacterial pathogen Pseudomonas syringae. Free radical scavenging potential of AgNPs was investigated using 1,1‐diphenyl‐2‐picryl hydroxyl and 2,2‐azinobis (3‐ethylbenzothiazoline)‐6‐sulphonic acid assays which revealed that the synthesised AgNPs act as a potent radical scavenger. The catalytic efficiency of the synthesised AgNPs was investigated for azo dyes, methyl orange (MO), methylene blue (MB) and reduction of o‐nitrophenol to o‐aminophenol. The results portrayed that AgNPs act as an effective nanocatalyst to degrade MO to hydrazine derivatives, MB to leucomethylene blue, and o‐nitro phenol to o‐amino phenolInspec keywords: catalysis, dyes, electron diffraction, nanofabrication, silver, catalysts, surface plasmon resonance, reduction (chemical), free radicals, nanoparticles, transmission electron microscopy, nanobiotechnology, X‐ray diffraction, microorganisms, organic compounds, Fourier transform spectra, nanomedicine, visible spectra, antibacterial activity, infrared spectra, ultraviolet spectraOther keywords: silver nanoparticles, musa paradisiaca, synergistic combating effect, free radical scavenging activity, catalytic efficiency, M. paradisiaca, bio‐reduction, ultraviolet–visible spectroscopy, surface plasmon resonance extinction peak, Fourier transform infrared spectroscopy, X‐ray diffraction pattern, selected area electron diffraction patterns, radical scavenging potential, potent radical scavenger, size 420.0 nm, size 15.0 nm, Ag⁺      

Green synthesis of AgCl/Ag3 PO4 nanoparticle using cyanobacteria and assessment of its antibacterial,colorimetric detection of heavy metals and antioxidant properties

In this study, the extract of two strains of cyanobacteria was used for the synthesis of silver nanoparticles (NPs). UV–vis spectroscopy, X‐ray diffraction, dynamic light scattering and field emission scanning electron microscopy (FESEM) analyses were carried out to characterise the NPs. The antioxidant activity and heavy metal detection properties were investigated; moreover, their minimum inhibitory concentration and minimum bactericidal concentration against the multi‐drug resistant bacteria were determined. The most abundant materials in these extracts were carbohydrates, so the biosynthesis of NPs using exopolysaccharide (EPS) was also investigated. The surface plasmon resonance of NPs had a peak at 435 nm and EPS NPs at 350–450 nm. The NPs produced by Nostoc sp. IBRC‐M5064 extract revealed the face‐centred cubic (fcc) structure of AgCl, while NPs of N. pruniforme showed the fcc crystalline structure of Ag₃ PO₄ and AgCl. The FESEM showed the spherical shape of these NPs. The AgCl/Ag₃ PO₄ colloid, in comparison with AgCl, showed better antioxidant activity and antibacterial effect. The heavy metal detection analysis of NPs revealed that the NPs of both stains involved in Hg (NO₃)₂ detection.Inspec keywords: drugs, light scattering, silver, biochemistry, surface plasmon resonance, X‐ray diffraction, silver compounds, antibacterial activity, ultraviolet spectra, nanoparticles, visible spectra, colloids, microorganisms, nanofabrication, field emission scanning electron microscopy, chemical sensors, nanosensorsOther keywords: cyanobacteria, antibacterial detection, colorimetric detection, dynamic light scattering, antioxidant activity, heavy metal detection analysis, silver nanoparticle synthesis, field emission scanning electron microscopy analysis, UV‐visible spectroscopy analysis, X‐ray diffraction analysis, inhibitory concentration, exopolysaccharide, surface plasmon resonance, Nostoc sp. IBRC‐M5064 extract, face‐centred cubic crystalline structure, FESEM, spherical shape, antibacterial effect, multidrug resistant bacteria, wavelength 350.0 nm to 450.0 nm, AgCl‐Ag₃ PO₄ , Ag     

Green synthesis of silver nanoparticle by cauliflower extract: characterisation and antibacterial activity against storage

Green synthesis of silver nanoparticles (AgNPs) was accomplished using different volumes of cauliflower extract and 0.001 M silver nitrate solution at 80°C for 15 min. A brownish‐red solution of AgNPs formed was tested by ultraviolet–visible absorption spectroscopy, Fourier‐transform infrared (FTIR), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). Surface plasmon resonance of AgNPs appeared at 416 nm. Also, the kinetic of AgNPs formation was studied and follows a sigmoidal pattern. Storing time was studied for the freshly prepared AgNPs after 60 days. FTIR analysis shows the adsorption of active components on AgNPs surface, and these components are responsible for reduction besides working as a stabiliser like a capping agent, also FTIR analysis of AgNPs after storage showed no change in peaks location. The SEM exhibited a globular shape of AgNPs, and the particle size ranged from 25 to 100 nm, while the XRD particle size calculation was 25 nm with cubic phase lattice. The antibacterial activity was tested against Gram‐positive and ‐negative bacteria showed an inhibition zone of 16–27 mm and the antibacterial activity tested for the same bacteria after storage for about 10 months showed an inhibition zone of 6–10 mm.Inspec keywords: microorganisms, reduction (chemical), nanofabrication, surface plasmon resonance, silver, transmission electron microscopy, nanoparticles, particle size, visible spectra, ultraviolet spectra, adsorption, antibacterial activity, scanning electron microscopy, X‐ray diffraction, Fourier transform infrared spectra, nanomedicineOther keywords: antibacterial activity, green synthesis, silver nanoparticle, brownish‐red solution, surface plasmon resonance, FTIR analysis, active components, silver nitrate solution, ultraviolet‐visible absorption spectroscopy, AgNP surface, cauliflower extract, Fourier‐transform infrared spectroscopy, scanning electron microscopy, SEM, X‐ray diffraction, XRD, sigmoidal pattern, storing time, adsorption, stabiliser, capping agent, globular shape, particle size, cubic phase lattice, Gram‐positive bacteria, Gram‐negative bacteria, inhibition zone, reduction, time 60.0 d, temperature 80.0 degC, time 15.0 min, wavelength 416.0 nm, Ag     

Biomimetic production,characterisation, in vitro cytotoxic and anticancer assessment of aqueous extract‐mediated AgNPs of Teucrium stocksianum Boiss

Owing to the numerous biological applications, cost effectiveness and low cytotoxicity of the biomimetic nanoparticles (NPs), the authors optimised the production of silver NPs (AgNPs) using aqueous extract of Teucrium stocksianum Boiss. The NPs were characterised by ultraviolet‐visible (UV‐vis) spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS) and Fourier transform‐infrared spectroscopy (FTIR). The UV‐vis spectroscopy revealed a surface plasmon resonance (410‐440 nm) at an incubation temperature of 90°C when 1 mM Ag nitrate combined to 5 mg/ml extract concentration in the ratio of 1:10. DLS results show an average zeta size of ∼44.61 nm and zeta potential of −15.3 mV. SEM and XRD confirmed the high crystallinity and cubical symmetry with an average size below 100 nm. FTIR measurement shows the presence of various functional groups, responsible for the capping and reduction of Ag metal. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide cell viability assay shows that AgNPs are less cytotoxic to J774 and L929 cells as compared with enhanced anticancer activity with low IC50 concentrations (68.24 µg/ml) against Michigan Cancer Foundation‐7 (MCF‐7) cells. The ethidium bromide/acridine orange assay shows that the AgNPs kill the cell by apoptosis. Overall, the results show that AgNPs possesses potent anticancer activities.Inspec keywords: cellular biophysics, cancer, nanobiotechnology, nanomedicine, ultraviolet spectra, X‐ray diffraction, scanning electron microscopes, light scattering, patient treatmentOther keywords: anticancer assessment, in vitro cytotoxic assessment, aqueous extract‐mediated AgNPs, Teucrium stocksianum Boiss, nanoparticles, biological applications, biosynthesis, silver NPs, X‐ray diffraction, scanning electron microscopy, dynamic light scattering, Fourier transform‐infrared spectroscopy, UV‐vis spectroscopy, surface plasmon resonance, extract concentration, zeta potential, high crystallinity, FTIR measurement, amide molecules, viability assay, enhanced anticancer activity, potent anticancer activities     

Plasma treated fabrics coated with naturally derived Ag‐NPs for biomedical application

Ethnic value of many known plants are underexploited for medicinal application besides their proven traditional qualities. One such plant known for wound healing is Tridax procumbens. This plant has wound healing property and is commercially unexploited. Silver nanoparticle (Ag‐NP) were synthesized using this plant extracts using different solvents (methanol, ethyl acetate and aqueous), which exhibit resonance at 426, 424 and 418 nm, respectively. This plant‐mediated Ag‐NPs have strong anti‐bactericidal activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyogenes, Klebsiella pneumonia, Serratia marcescens and Bacillus subtilis with methanol extract. Further instance, elemental composition was confirmed by energy dispersive X‐ray analysis and particle size ranges were observed at 80–200 nm with spherical shape nanoparticles by scanning electron microscopy and transmission electron microscopy analysis. The biocompatibility of Ag‐NPs was assessed using fibroblast cell line (L929) by MTT assay with 109.35 µg IC₅₀ value. The oxygen plasma treated and non‐treated bamboo spunlaced nonwoven fabrics were coated with the Ag‐NPs by exhaust method. Contact angle and water retention revealed significant difference in absorption ability of plasma treated fabric. Field emission scanning electron microscopy revealed the presence of Ag‐NPs in plasma coated fabrics. The fabricated cloth was studied for anti‐microbial and microbial penetration ability.Inspec keywords: solvents (industrial), organic compounds, woven composites, field emission scanning electron microscopy, plasma materials processing, contact angle, transmission electron microscopy, X‐ray diffraction, fabrics, biomedical materials, wounds, silver, nanoparticles, particle size, nanofabrication, thermal analysis, antibacterial activity, microorganisms, X‐ray chemical analysisOther keywords: biomedical application, ethnic value, medicinal application, wound healing property, silver nanoparticle synthesis, methanol, ethyl acetate, Escherichia coli, Pseudomonas aeruginosa, Streptococcus pyogenes, Klebsiella pneumonia, nonwoven fabrics, field emission scanning electron microscopy, plasma coated fabrics, fabricated cloth, solvents, antibactericidal activity, Staphylococcus aureus, particle size, transmission electron microscopy, oxygen plasma treatment, bamboo material, Tridax procumbens extracts, Serratia marcescens, Bacillus subtilis, elemental composition, energy dispersive X‐ray analysis, scanning electron microscopy, material biocompatibility, fibroblast cell line, exhaust method, contact angle, water retention, absorption ability, antimicrobial property, microbial penetration ability, size 424.0 nm, size 418.0 nm, size 80.0 nm to 200.0 nm, size 426.0 nm, Ag     

Efficacy of mycosynthesised AgNPs from Earliella scabrosa as an in vitro antibacterial and wound healing agent

The silver nanoparticles (AgNPs) with their unique chemical and physical properties are proving as a new therapeutical agent. In the present study, the AgNPs synthesised from an aqueous extract of a macrofungus, Earliella scabrosa, were characterised by field emission scanning electron microscopy (FESEM), energy dispersive X‐ray analysis (EDX), high‐resolution transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and further evaluate for its in vitro antibacterial and wound healing efficacy. The mycosynthesised AgNPs exhibited the surface plasmon resonance peak at 410 nm with good stability over a period of a month. The FESEM and EDX analyses revealed the spherical‐shaped AgNPs of an average size of 20 nm and the presence of elemental Ag, respectively. The XRD pattern showed the crystalline nature of AgNPs. The FTIR spectra confirmed the conversion of Ag⁺ ions to AgNPs due to reduction by biomolecules of macrofungus extract. The mycosynthesised AgNPs showed effective antibacterial activity against two Gram‐positive bacteria, namely Bacillus subtilis and Staphylococcus aureus, and two Gram‐negative bacteria Escherichia coli and Pseudomonas aeruginosa. The pathogens were highly sensitive to AgNPs, whereas less sensitive to AgNO₃. The mycosynthesised AgNPs showed significant wound healing potential with 68.58% of wound closure.Inspec keywords: surface plasmon resonance, wounds, X‐ray diffraction, nanoparticles, molecular biophysics, nanomedicine, antibacterial activity, biomedical materials, reduction (chemical), silver, microorganisms, X‐ray chemical analysis, nanofabrication, transmission electron microscopy, particle size, field emission scanning electron microscopy, Fourier transform infrared spectraOther keywords: high‐resolution transmission electron microscopy, healing efficacy, mycosynthesised AgNPs, spherical‐shaped AgNPs, wound healing agent, in vitro antibacterial efficacy, Earliella scabrosa, silver nanoparticles, physical properties, chemical properties, therapeutical agent, aqueous extract, macrofungus, field emission scanning electron microscopy, FESEM, energy dispersive X‐ray analysis, EDX, X‐ray diffraction, XRD, Fourier transform infrared spectroscopy, FTIR spectroscopy, surface plasmon resonance peak, crystalline nature, biomolecules, Gram‐positive bacteria, Bacillus subtilis, Staphylococcus aureus, Gram‐negative bacteria, Escherichia coli, Pseudomonas aeruginosa, pathogens, wound closure, Ag     

Green synthesis of the Ag/ZnO nanocomposite using Valeriana officinalis L. root extract: application as a reusable catalyst for the reduction of organic dyes in a very short time

A facile and green synthesis of the Ag/ZnO nanocomposite by extract of Valeriana officinalis L. root in the absence of any stabiliser or surfactant has been reported in this work. The green synthesised Ag/ZnO nanocomposite was characterised by Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X‐ray spectroscopy (EDS), elemental mapping, Fourier‐Transform infrared (FT‐IR), X‐ray diffraction analysis (XRD) and UV‐Vis spectroscopy. According to SEM and TEM images, the Ag and ZnO particles are spherical with diameters of less than 20 and 40–50 nm, respectively. The Ag NPs/ZnO nanocomposite proved to be an effective catalyst in the reduction of various dyes including methyl orange (MO), Congo red (CR) and methylene blue (MB) in the presence of NaBH₄ in aqueous media at ambient temperature. A maximum degradation (100%) of dyes was performed using Ag/ZnO nanocomposite. The extraordinary performance of the prepared Ag/ZnO nanocomposite is attributed to the synergetic effect induced by both ZnO and Ag NPs in the catalytic degradation of organic dyes. The catalyst could be reused and recovered several times with no significant loss of catalytic activity.Inspec keywords: nanocomposites, silver, zinc compounds, II‐VI semiconductors, nanofabrication, catalysts, reduction (chemical), field emission electron microscopy, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectra, ultraviolet spectra, visible spectra, X‐ray diffraction, surface morphology, nanoparticles, dyesOther keywords: green synthesis, nanocomposite, Valeriana officinalis L. root extract, reusable catalyst, reduction, organic dyes, surfactant, field emission scanning electron microscopy, transmission electron microscopy, energy dispersive X‐ray spectroscopy, elemental mapping, Fourier‐transform infrared spectroscopy, X‐ray diffraction analysis, surface morphology, nanoparticles, methyl orange, congo red, methylene blue, UV–Vis spectroscopy, size 40 nm to 50 nm, wavelength 493 nm, wavelength 465 nm, wavelength 663 nm, Ag‐ZnO     

Green synthesis,characterisation and biological evaluation of plant‐based silver nanoparticles using Quercus semecarpifolia Smith aqueous leaf extract

The development of reliable and green methods for the fabrication of metallic nanoparticles (NPs) has many advantages in the field of nanotechnology. In this direction, the present work describes an eco‐friendly and cost‐effective protocol for the production of silver NPs (AgNPs) using an aqueous extract of Quercus semecarpifolia leaves. Different techniques were carried out for the characterisation of the synthesised AgNPs. The ultraviolet–visible spectroscopic analysis showed the highest absorbance peak at 430 nm. The particle size and structure were confirmed by scanning electron microscopy as well as transmission electron microscopy (TEM) analysis. From TEM imaging, it was revealed that the formed particles were spherical with an average size of 20–50 nm. The crystalline nature of the NPs was determined by X‐ray powder diffraction patterns. Thermogravimetry and differential thermal analysis were also evaluated by a temperature increment from 100 to 1000°C. Bio‐inspired synthesis of AgNPs was performed for their pharmacological evaluation in relation to the activities of the crude methanolic, n ‐hexane, chloroform, ethyl acetate, and aqueous extracts. Good cytotoxic activity was exhibited by the green‐synthesised AgNPs (77%). Furthermore, the AgNPs were found to exhibit significant antioxidant activity at 300 μg/ml (82%). The AgNPs also exhibited good phytotoxic potential (75%).Inspec keywords: scanning electron microscopy, toxicology, visible spectra, particle size, nanofabrication, nanomedicine, transmission electron microscopy, silver, ultraviolet spectra, differential thermal analysis, nanoparticles, X‐ray diffraction, botany, biochemistry, cellular biophysicsOther keywords: green synthesis, biological evaluation, plant‐based silver nanoparticles, reliable methods, metallic nanoparticles, eco‐friendly cost‐effective protocol, silver NPs, ultraviolet–visible spectroscopic analysis, highest absorbance peak, particle size, structure, transmission electron microscopy analysis, TEM imaging, crystalline nature, X‐ray powder diffraction patterns, differential thermal analysis, pharmacological evaluation, aqueous extracts, good cytotoxic activity, significant antioxidant activity, AgNPs exhibited good phytotoxic potential, bio‐inspired synthesis, Quercus semecarpifolia Smith aqueous leaf extract, scanning electron microscopy, thermogravimetry, crude methanolic, n‐hexane, chloroform, ethyl acetate, phytotoxic potential, haemagglutination activity, size 20.0 nm to 50.0 nm, wavelength 430.0 nm, temperature 100 degC to 1000 degC, Ag     

Eco‐friendly synthesis of silver and gold nanoparticles with enhanced antimicrobial,antioxidant, and catalytic activities

The present work is emphasised on the bio‐fabrication of silver and gold nanoparticles in a single step by a microwave‐assisted method using the leaf extract of Synedrella nodiflora as both reducing and stabilising agent. The synthesised nanoparticles are highly stable and show surface plasmon resonance peak at 413 and 535 nm, respectively, for silver and gold nanoparticles in UV–Vis spectrum. The functional group responsible for the reduction of metal ions were obtained from Fourier transform infrared spectroscopy. The crystalline nature of nanoparticles with face‐centred cubic geometry was confirmed by the X‐ray diffraction and selected area electron diffraction patterns. The morphology and sizes of the silver and gold nanoparticles were obtained from transmission electron microscopy images. The nanoparticles exhibit effective antimicrobial activities against various pathogenic strains. These antimicrobial properties were analysed by employing agar well diffusion method. The nanoparticles show significant antioxidant properties, and it was determined using 2, 2‐diphenyl‐1‐picrylhydrazyl assay. The nanoparticles also show potent catalytic activity in the degradation of anthropogenic pollutant dyes Congo red and eosin Y by excess NaBH₄. Thus, the current study demonstrates the potential use of S. nodiflora as a reducing and stabilising agent for the synthesis of silver and gold nanoparticles and their relevance in the field of biomedicine and catalysis.Inspec keywords: transmission electron microscopy, visible spectra, surface plasmon resonance, nanofabrication, ultraviolet spectra, field emission electron microscopy, reduction (chemical), nanocomposites, microorganisms, nanoparticles, dyes, silver, X‐ray diffraction, nanomedicine, gold, antibacterial activity, electron diffraction, infrared spectra, particle size, Fourier transform spectra, scanning electron microscopy, catalysis, crystal growth from solutionOther keywords: synthesised nanoparticles, gold nanoparticles, catalytic activities, electron diffraction patterns, antimicrobial activities, antioxidant activities, transmission electron microscopy images, X‐ray diffraction, 2,2‐diphenyl‐1‐picrylhydrazyl assay, Synedrella nodiflora, UV–Vis spectrum, silver nanoparticles, biofabrication, surface plasmon resonance, Fourier transform infrared spectroscopy, face‐centred cubic geometry, area electron diffraction patterns, pathogenic strains, agar well diffusion method, anthropogenic pollutant dyes, Congo red, eosin Y, wavelength 413.0 nm, wavelength 535.0 nm, Au, Ag     

Preparation of silver iodide nanoparticles using laser ablation in liquid for antibacterial applications

In this study, the authors reported the first synthesis process of silver iodide (AgI) nanoparticles (NPs) by pulsed laser ablation of the AgI target in deionised distilled water. The optical and structural properties of AgI NPs were investigated by using UV–vis absorption, X‐ray diffraction, scanning electron microscope (SEM), energy dispersive X‐ray, Fourier transform infrared spectroscopy, and transmission electron microscope (TEM). The optical data showed the presence of plasmon peak at 434 nm and the optical bandgap was found to be 2.6 eV at room temperature. SEM results confirm the agglomeration and aggregation of synthesised AgI NPs. TEM investigation showed that AgI NPs have a spherical shape and the average particle size was around 20 nm. The particle size distribution was the Gaussian type. The results showed that the synthesised AgI NPs have antibacterial activities against both bacterial strains and the activities were more potent against gram‐negative bacteria.Inspec keywords: antibacterial activity, nanoparticles, X‐ray chemical analysis, particle size, transmission electron microscopy, X‐ray diffraction, nanofabrication, scanning electron microscopy, visible spectra, ultraviolet spectra, silver compounds, pulsed laser deposition, Fourier transform infrared spectra, optical constants, energy gap, aggregationOther keywords: synthesis process, pulsed laser ablation, AgI target, deionised distilled water, optical properties, structural properties, UV–vis absorption, X‐ray diffraction, transmission electron microscope, optical data, optical bandgap, antibacterial activities, silver iodide nanoparticles, energy dispersive X‐ray analysis, SEM, wavelength 434.0 nm, temperature 293 K to 298 K, AgI     

Carpogenic ZnO nanoparticles: amplified nanophotocatalytic and antimicrobial action

This investigation has for the first time utilised environmental resource Prunus cerasifera seed extract phytochemicals for the green synthesis of carpogenic ZnO nanoparticles (NPs). Spherical morphology and size range of 56.57–107.70 nm at variable calcination temperatures without the use of any external reducing agent was obtained. The synthesised NPs exhibited hexagonal wurtzite geometry with an average crystal size 5.62 nm and a band gap of 3.4 eV. Carpogenic NPs were investigated for optical, compositional, morphological, and phytochemical make up via ultraviolet spectroscopy (UV–Vis), Fourier transform infrared analysis, X‐ray powder diffraction, scanning electron microscopy, and gas chromatography and mass spectrometry. Carpogenic NPs degraded methyl red up to 83% with pseudo‐first‐order degradation kinetics (R ²  = 0.88) in 18 min signifying their remediation role in environment in conformity with all principles of green chemistry. Photocatalytic assays were performed in direct solar irradiance. Nine pathogens of biomedical and agricultural significance having multi‐drug resistance were inhibited in vitro via the Kirby–Bauer disc diffusion assay. The enhanced photocatalytic and antimicrobial inhibition not only makes carpogenic ZnO NPs a future photo‐degradative candidate for environmental remediation but also a nanofertiliser, nanofungicide, and nanobactericide synthesised via bioinspired, biomimetic, green, and unprecedented route.Inspec keywords: visible spectra, Fourier transform spectra, nanocomposites, nanobiotechnology, transmission electron microscopy, X‐ray diffraction, biomimetics, zinc compounds, catalysis, antibacterial activity, microorganisms, chromatography, scanning electron microscopy, ultraviolet spectra, nanoparticles, photochemistry, infrared spectra, calcination, nanofabricationOther keywords: antimicrobial action, environmental resource, prunus cerasifera seed, phytochemicals, green synthesis, variable calcination temperatures, hexagonal wurtzite geometry, X‐ray powder diffraction, gas chromatography, mass spectrometry, pseudofirst‐order degradation kinetics, green chemistry, Aspergillus niger, Aspergillus flavus, Aspergillus terreus, antimicrobial inhibition, environmental remediation, photocatalytic inhibition, carpogenic nanoparticles, nanophotocatalytic action, size 5.62 nm, electron volt energy 3.4 eV, time 18.0 min, size 56.57 nm to 107.7 nm, ZnO     

Comparative antileishmanial efficacy of the biosynthesised ZnO NPs from genus Verbena

This study describes ZnO NPs biosynthesis using leaf extracts of Verbena officinalis and Verbena tenuisecta. The extracts serve as natural reducing, capping and stabilization facilitators. Plant extracts phytochemical analysis, revealed that V. officinalis showed higher total phenolic and flavonoid content (22.12 and 6.38 mg g ⁻¹ DW) as compared to V. tennuisecta (12.18 and 2.7 mg g ⁻¹ DW). ZnO NPs were characterised by ultraviolet–visible spectroscopy, Fourier transform infrared, X‐ray diffraction, scanning electron microscope, transmission electron microscopy (TEM) and energy dispersive X‐ray. TEM analysis of ZnO NPs reveals rod and flower shapes and were in the range of 65–75 and 14–31 nm, for V. tenuisecta and V. officinalis, respectively. Bio‐potential of ZnO NPs was examined through their leishmanicidal potential against Leishmania tropica. ZnO NPs showed potent leishmanicidal activity with 250 µg ml⁻¹ being the most potent concentration. V. officinalis mediated ZnO NPs showed more potent leishmanicidal activity compared to V. tenuisecta mediated ZnO NPs due to their smaller size and increased phenolics doped onto its surface. These results can be a step forward towards the development of novel compounds that can efficiently replace the current medication schemes for leishmaniasis treatment.Inspec keywords: ultraviolet spectra, nanomedicine, nanostructured materials, visible spectra, X‐ray diffraction, antibacterial activity, nanoparticles, zinc compounds, scanning electron microscopy, microorganisms, nanofabrication, drugs, transmission electron microscopy, X‐ray chemical analysis, health and safety, particle size, renewable materials, diseases, Fourier transform infrared spectraOther keywords: flavonoid content, natural reducing stabilisation facilitators, ZnO nanoparticles synthesis, antileishmanial efficacy, Verbena tennuisecta, Verbena officinales, phytochemical analysis, phenolic content, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, energy dispersive X‐ray analysis, particle size, leishmaniasis treatment, leaf extracts, medication scheme, stabilisation facilitator, capping facilitator, size 14.0 nm to 31.0 nm, size 65.0 nm to 75.0 nm, ZnO     

Biosynthesis of AgNPs using aqueous leaf extract of Ipomoea eriocarpa and their anti‐inflammatory effect on carrageenan‐induced paw edema in male Wistar rats

Silver nanoparticles (AgNPs) were synthesised from aqueous Ag nitrate through a simple, competent and eco‐friendly method using the leaf extract of Ipomoea eriocarpa as reducing as well as capping agent. Ultraviolet–visible absorption spectroscopy was used to confirm the formation of AgNPs which displayed the substantiation of surface plasmon bands at 425 nm. The NPs were also characterised using Fourier transformer infrared spectroscopy, X‐ray diffraction method, transmission electron microscope and zeta potential. The characterisation study confirmed the formation of AgNPs, their spherical shape and average diameter of 12.85 ± 8.65 nm. Zeta potential value of −20.5 mV suggested that the AgNPs are stable in the suspension. The aqueous extract and the AgNPs were further screened for in vivo anti‐inflammatory activity using carrageenan‐induced paw edema in male Wistar rats. The study demonstrated that the AgNPs (1 ml kg⁻¹) had a significant (p  < 0.05) anti‐edemic effect and inhibition was observed from the first hour (21.31 ± 1.34) until the sixth hour (52.67 ± 1.41), when the inhibitory effect was greatest and superior to the aqueous extract and the standard, diclofenac.Inspec keywords: silver, nanoparticles, nanofabrication, ultraviolet spectra, visible spectra, absorption coefficients, surface plasmons, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, suspensions, drugs, nanomedicineOther keywords: biosynthesis, aqueous leaf extract, ipomoea eriocarpa, antiinflammatory effect, carrageenan‐induced paw edema, male Wistar rats, silver nanoparticles, aqueous nitrate, capping agent, ultraviolet‐visible absorption spectroscopy, surface plasmon band, Fourier transformer infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, zeta potential, spherical shape, suspension, aqueous extract, in vivo antiinflammatory activity, antiedemic effect, inhibitory effect, diclofenac, wavelength 425 nm, size 12.85 nm to 8.65 nm, Ag     

Phytofabrication of silver nanoparticles using Bacopa monnieri leaf extract and its antibacterial activity as well as oxidative stress‐induced apoptosis of lung cancer

The biological method for synthesis of silver nanoparticles (AgNPs) using Bacopa monneri leaves and its anti‐proliferation against human lung adenocarcinoma cell line (A549) was studied. The AgNPs synthesis was determined by an ultraviolet–visible spectrum and was confirmed primarily by the colour change and surface plasmon resonance was observed at 450 nm and its reduction of functional groups stretched in AgNPs was identified by Fourier transform infrared and the crystalline nature of AgNPs was confirmed by X‐ray diffraction. The structural morphology of the AgNPs was found to be spherical and polygonal shape and size (> 35 nm) were determined by field emission scanning electron microscopy analysis and its purity was identified by energy dispersive analysis of X‐rays (EDAX). A further, antibacterial activity of biosynthesised AgNPs against Gram negative and Gram positive bacteria was assessed. The cytotoxic effect of synthesised AgNPs was analysed against human lung adenocarcinoma cells by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. The GI₅₀ was found to be 20 µg/ml at 24 h incubation. The apoptosis cells containing condensate and marginalised chromatin stages were analysed by propidium iodide staining and DNA damage was observed in A549 treated cells. The present study strongly emphasised that the bioactive molecule‐coated AgNPs could have potential for biomedical applications and significant anticancer effects against human lung adenocarcinoma cells.Inspec keywords: antibacterial activity, biomedical materials, lung, cancer, oxidation, nanoparticles, silver, nanofabrication, nanomedicine, cellular biophysics, ultraviolet spectra, visible spectra, surface plasmon resonance, Fourier transform infrared spectra, X‐ray diffraction, particle size, field emission electron microscopy, scanning electron microscopy, X‐ray chemical analysis, microorganisms, toxicology, DNA, molecular biophysics, molecular configurationsOther keywords: silver nanoparticles, phytofabrication, Bacopa monnieri leaf extract, antibacterial activity, oxidative stress‐induced apoptosis, biological method, antiproliferation, human lung adenocarcinoma cell line A549, AgNPs synthesis, ultraviolet‐visible spectrum, colour change, surface plasmon resonance, stretched functional groups, Fourier transform infrared spectra, crystalline nature, X‐ray diffraction, geometric spherical shape, polygonal shape, field emission scanning electron microscopy analysis, EDAX, biosynthesised AgNPs, gram negative bacteria, gram positive bacteria, cytotoxic effect, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay, incubation, apoptosis cells, condensate, marginalised chromatin stages, propidium iodide staining, DNA damage, A549 treated cells, bioactive molecule‐coated AgNPs, biomedical applications, anticancer effects, time 24 h, Ag