Bio‐green synthesis ZnO‐NPs in Brassica napus pollen extract: biosynthesis,antioxidant, cytotoxicity and pro‐apoptotic properties

The bio‐green methods of synthesis nanoparticles (NPs) have advantages over chemo‐physical procedures due to cost‐effective and ecofriendly products. The goal of current investigation is biosynthesis of zinc oxide NPs (ZnO‐NPs) and evaluation of their biological assessment. Water extract of Brassica napus pollen [rapeseed (RP)] prepared and used for the synthesis of ZnO‐NPs and synthesised ZnO‐NP characterised using ultraviolet–visible, X‐ray diffraction, Fourier‐transform infrared spectroscopy, field emission scanning electron microscope and transmission electron microscope. Antioxidant properties of ZnO‐NPs, cytotoxic and pro‐apoptotic potentials of NPs were also evaluated. The results showed that ZnO‐NPs have a hexagonal shape with 26 nm size. ZnO‐NPs synthesised in RP (RP/ZnO‐NPs) exhibited the good antioxidant potential compared with the butylated hydroxyanisole as a positive control. These NPs showed the cytotoxic effects against breast cancer cells (M.D. Anderson‐Metastasis Breast cancer (MDA‐MB)) with IC₅₀ about 1, 6 and 6 μg/ml after 24, 48 and 72 h of exposure, respectively. RP/ZnO‐NPs were found effective in increasing the expression of catalase enzyme, the enzyme involved in antioxidants properties of the cells. Bio‐green synthesised RP/ZnO‐NPs showed antioxidant and cytotoxic properties. The results of the present study support the advantages of using the bio‐green procedure for the synthesis of NPs as an antioxidant and as anti‐cancer agents.Inspec keywords: II‐VI semiconductors, wide band gap semiconductors, ultraviolet spectra, toxicology, X‐ray diffraction, biochemistry, zinc compounds, nanomedicine, enzymes, biomedical materials, particle size, antibacterial activity, transmission electron microscopy, molecular biophysics, visible spectra, nanofabrication, cellular biophysics, nanoparticles, cancer, field emission scanning electron microscopy, Fourier transform infrared spectra, semiconductor growthOther keywords: bio‐green synthesis ZnO‐NPs, zinc oxide NPs, synthesised ZnO‐NP, field emission scanning electron microscope, transmission electron microscope, antioxidant properties, bio‐green synthesised RP‐ZnO‐NPs, Fourier‐transform infrared spectroscopy, X‐ray diffraction, breast cancer cells MDA‐MB, pro‐apoptotic potentials, cytotoxic effects, catalase enzyme, bio‐green procedure, time 48.0 hour, time 72.0 hour, size 26.0 nm, time 24.0 hour, ZnO     

Optimised synthesis of ZnO‐nano‐fertiliser through green chemistry: boosted growth dynamics of economically important L. esculentum

Mounting‐up economic losses to annual crops yield due to micronutrient deficiency, fertiliser inefficiency and increasing microbial invasions (e.g. Xanthomonas cempestri attack on tomatoes) are needed to be solved via nano‐biotechnology. So keeping this in view, the authors’ current study presents the new horizon in the field of nano‐fertiliser with highly nutritive and preservative effect of green fabricated zinc oxide‐nanostructures (ZnO‐NSs) during Lycopersicum esculentum (tomato) growth dynamics. ZnO‐NS prepared via green chemistry possesses highly homogenous crystalline structures well‐characterised through ultraviolet and visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscope. The ZnO‐NS average size was found as small as 18 nm having a crystallite size of 5 nm. L. esculentum were grown in different concentrations of ZnO‐NS to examine the different morphological parameters includes time of seed germination, germination percentage, the number of plant leaves, the height of the plant, average number of branches, days count for flowering and fruiting time period along with fruit quantity. Promising results clearly predict that bio‐fabricated ZnO‐NS at optimum concentration resulted as growth booster and dramatically triggered the plant yield.Inspec keywords: zinc compounds, II‐VI semiconductors, wide band gap semiconductors, nanostructured materials, nanofabrication, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, X‐ray diffraction, scanning electron microscopy, crystallites, biomedical materials, nanomedicineOther keywords: ZnO‐nanofertiliser, green chemistry, boosted growth dynamics, L. esculentum, mounting‐up economic losses, micronutrient deficiency, fertiliser inefficiency, microbial invasions, Xanthomonas cempestri, nanobiotechnology, zinc oxide‐nanostructures, Lycopersicum esculentum, high‐homogenous crystalline structures, ultraviolet spectroscopy, visible spectroscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, crystallite size, morphological parameters, seed germination, germination percentage, plant leaves, ZnO     

Sustainable green synthesis of silver nanoparticles by using Rangoon creeper leaves extract and their spectral analysis and anti‐bacterial studies

The plant‐based biological molecules possess exceptionally controlled assembling properties to make them suitable in the synthesis of metal nanoparticles. In the present study, an efficient simple one‐pot method was employed for the synthesis of silver nanoparticles (SNPs) from the Rangoon creeper (RC) aqueous leaf extract. Biomolecules present in the leaf extract play a significant role as reducing agent as well as capping agent in the formation of RC‐SNPs. The formation of RC‐SNPs was confirmed by using several analytical techniques such as Fourier‐transform infrared spectroscopy and ultraviolet–visible spectrophotometer studies. The presence of a sharp surface plasmon resonance peak at 449 nm showed the formation of RC‐SNPs. X‐ray diffraction analysis showed the crystalline nature of the RC‐SNPs with a face‐centred cubic structure. Elemental analysis of RC‐SNPs was done by using energy‐dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy. The morphology of RC‐SNPs was examined by transmission electron microscopy (TEM) in the nano range 12 nm, and thermogravimetric‐differential thermal analysis demonstrated the mechanical strength of RC‐SNPs at various temperatures. The authors’ newly synthesised RC‐SNPs exhibited significant anti‐bacterial activity against Staphylococcus aureus and Escherichia coli. Inspec keywords: silver, nanoparticles, X‐ray photoelectron spectra, antibacterial activity, ultraviolet spectra, microorganisms, X‐ray chemical analysis, differential thermal analysis, X‐ray diffraction, transmission electron microscopy, visible spectra, nanofabrication, surface plasmon resonance, Fourier transform infrared spectra, mechanical strengthOther keywords: silver nanoparticles, ultraviolet–visible spectrophotometry, antibacterial activity, sustainable green synthesis, plant‐based biological molecules, assembling properties, reducing agent, capping agent, Fourier‐transform infrared spectroscopy, surface plasmon resonance, Rangoon creeper aqueous leaf extract, X‐ray diffraction, face‐centred cubic structure, elemental analysis, energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, transmission electron microscopy, TEM, thermogravimetric‐differential thermal analysis, mechanical strength, Staphylococcus aureus, Escherichia coli, Ag     

Biosynthesis of zinc oxide nanoparticles by petals extract of Rosa indica L., its formulation as nail paint and evaluation of antifungal activity against fungi causing onychomycosis

Aim: The authors report the biological synthesis of zinc oxide nanoparticles (ZnO‐NPs) from the petals extract of Rosa indica L. (rose). Its efficacy was evaluated against two dermatophytes: namely: Trichophyton mentagrophytes and Microsporum canis which cause onychomycosis. The activity of antibiotics against the tested dermatophytes was enhanced, when evaluated in combination with ZnO‐NPs. Methods and results: The synthesised ZnO‐NPs were preliminary detected by using ultraviolet UV visible spectroscopy, which showed specific absorbance. The ZnO‐NPs were further characterised by nanoparticle tracking analysis (NTA), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X‐ray diffraction and Zetasizer. Moreover, nanoparticles containing nail paint (nanopaint) was formulated and its antifungal activity was also assessed against T. mentagrophytes and M. canis. ZnO‐NPs and formulated nanopaint containing ZnO‐NPs, both showed significant antifungal activity. The maximum activity was noted against M. canis and lesser against T. mentagrophytes. Minimum inhibitory concentration of ZnO‐NPs was also determined against the dermatophytes causing onychomycosis infection. Conclusion: ZnO‐NPs can be utilised as a potential antifungal agent for the treatment of onychomycosis after more experimental trials.Inspec keywords: diseases, zinc compounds, nanoparticles, nanofabrication, antibacterial activity, microorganisms, nanomedicine, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopy, X‐ray diffraction, biomedical materials, patient treatmentOther keywords: zinc oxide nanoparticle biosynthesis, Rosa indica L petals extract, nail paint, antifungal activity evaluation, dermatophyte, Trichophyton mentagrophytes, Microsporum canis, antibiotics activity, ultraviolet‐visible spectroscopy, nanoparticle tracking analysis, Fourier transform infrared spectroscopy, transmission electron microscopy, X‐ray diffraction, zetasizer, antifungal agent, onychomycosis treatment     

Analytical study of biosynthesised silver nanoparticles against multi‐drug resistant biofilm‐forming pathogens

The emergence of the huge number of multi‐drug resistant (MDR) bacteria requires an alternative to the drugs. Silver nanoparticles (AgNPs) are a strong candidate for this due to their bactericidal properties, which can be better concluded by understanding their morphology and chemistry. The study hypothesised that AgNPs synthesised using leaves of Syzygium cumini can be used to treat locally emerging MDRs forming biofilms on indwelling medical devices. Synthesised particles were characterised by methods like UV–visible spectroscopy, X‐ray powder diffraction, scanning electron microscopy, transmission electron microscopy, and Zetasizer. Fourier transform infrared spectroscopy, and high‐performance liquid chromatography were used to predict phytochemicals present in the leaves. The shape of particles is revealed to be relatively spherical, with average size to be around 10–100 nm. Phenolic compounds are attributed to the formation of nanoparticles, stability analysis shows particles to be stable, and zeta potential determined the surface charge to be −20.1 mV. Biosynthesised particles are found to possess efficient antibacterial activity MDR bacteria developing biofilms in medical devices; hence, it is concluded that S. cumini based NPs can be used to develop a layer on implant‐related medical devices. Toxicity evaluation against A594 cancer cells portrays AgNPs to be potential tumour reduction agents in a concentration‐dependent manner.Inspec keywords: silver, visible spectra, X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, chromatography, electrokinetic effects, cancer, biomedical materials, reduction (chemical), cellular biophysics, nanofabrication, nanoparticles, antibacterial activity, particle size, drugs, toxicology, nanomedicine, ultraviolet spectra, microorganisms, tumours, Fourier transform infrared spectraOther keywords: Syzygium cumini, biofilms, indwelling medical devices, UV‐visible spectroscopy, X‐ray powder diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, high‐performance liquid chromatography, biosynthesised particles, implant‐related medical devices, biosynthesised silver nanoparticles, multidrug resistant biofilm‐forming pathogens, multidrug resistant bacteria, MDR, bactericidal properties, morphology, scanning electron microscopy, s. cumini based NP, A594 cancer cells, tumour reduction, Ag     

Biosynthesis of zinc oxide nanoparticles using anjbar (root of Persicaria bistorta) extract and their cytotoxic effects on human breast cancer cell line (MCF‐7)

Biosynthesis of nanoparticles (NPs) using biomass is now one of the best methods for synthesising NPs due to their nontoxic and biocompatibility. Plants are the best choice among all biomass to synthesise large‐scale NPs. The objectives of this study were to synthesise zinc oxide nanoparticles (ZnO‐NPs) using Anjbar (root of Persicaria bistorta) [An/ZnO‐NPs] and investigate the cytotoxic and anti‐oxidant effects. For this purpose, the An/ZnO‐NPs were synthesised by using Bistort extract and characterised using UV–Visible spectroscopy, transmission electron microscope, field emission scanning electron microscope, x‐ray diffraction and Fourier‐transform infrared spectroscopy. The cytotoxic effects of the An/ZnO‐NPs on MCF‐7 cells were followed by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assays at 24, 48, and 72 h. Nuclear morphology changed and apoptosis in cells was investigated using acridine orange/propodium iodide (AO/PI) staining and flow cytometry analysis. The pure biosynthesised ZnO‐NPs were spherical in shape and particles sizes ranged from 1 to 50 nm. Treated MCF‐7 cells with different concentrations of ZnO‐NPs inhibited cell viability in a time‐ and dose‐dependent manner with IC50 about 32 μg/ml after 48 h of incubation. In flow cytometry analysis the sub‐G1 population, which indicated apoptotic cells, increased from 12.6% at 0 μg/ml (control) to 92.8% at 60 μg/ml, 48 h after exposure. AO/PI staining showed that the treated cells displayed morphologic evidence of apoptosis, compared to untreated groups. Inspec keywords: cancer, cellular biophysics, toxicology, particle size, nanofabrication, X‐ray diffraction, nanomedicine, nanoparticles, ultraviolet spectra, scanning electron microscopy, visible spectra, transmission electron microscopy, patient treatment, field emission electron microscopy, Fourier transform infrared spectra, drug delivery systemsOther keywords: anjbar, cytotoxic effects, human breast cancer cell line, biomass, transmission electron microscope, field emission scanning electron microscope, Fourier‐transform infrared spectroscopy, flow cytometry analysis, ZnO‐NPs inhibited cell viability, antioxidant effects, MCF‐7 cells, biosynthesised ZnO‐NP, biosynthesised ZnO‐NP, acridine orange‐propodium iodide staining, An‐ZnO‐NP, Persicaria bistorta, zinc oxide nanoparticle biosynthesis, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide     

Green synthesis of silver nanoparticles using Mentha pulegium and investigation of their antibacterial,antifungal and anticancer activity

A simple and eco‐friendly method for efficient synthesis of stable colloidal silver nanoparticles (AgNPs) using Mentha pulegium extracts is described. A series of reactions was conducted using different types and concentrations of plant extract as well as metal ions to optimize the reaction conditions. AgNPs were characterized by using UV–vis spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering, zetasizer, energy‐dispersive X‐ray spectroscopy (EDAX) and Fourier transform infrared spectroscopy (FTIR). At the optimized conditions, plate shaped AgNPs with zeta potential value of ‐15.7 and plasmon absorption maximum at 450 nm were obtained using high concentration of aqueous extract. Efficient adsorption of organic compounds on the nanoparticles was confirmed by FTIR and EDAX. The biogenic AgNPs displayed promising antibacterial activity on Escherichia coli, Staphylococcus aureus, and Streptococcus pyogenes. The highest antibacterial activity of 25 µg mL‐1 was obtained for all the strains using aqueous extract synthesized AgNPs. The aqueous extract synthesised AgNPs also showed considerable antifungal activity against fluconazole resistant Candida albicans. The cytotoxicity assay revealed considerable anticancer activity of AgNPs on HeLa and MCF‐7 cancer cells. Overall results indicated high potential of M. pulegium extract to synthesis high quality AgNPs for biomedical applications.Inspec keywords: silver, nanoparticles, nanofabrication, botany, antibacterial activity, biomedical materials, nanomedicine, ultraviolet spectra, visible spectra, transmission electron microscopy, atomic force microscopy, X‐ray chemical analysis, Fourier transform infrared spectra, electrokinetic effects, microorganisms, cellular biophysics, cancerOther keywords: antibacterial activity, antifungal activity, anticancer activity, stable colloidal silver nanoparticle, Mentha pulegium, plant extract, UV‐visible spectroscopy, transmission electron microscopy, atomic force microscopy, DLS, zetasizer, energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, methanolic extract, aqueous extract, plate‐shaped silver nanoparticle, zeta potential, plasmon absorption maximum, organic compounds adsorption, biogenic silver nanoparticle, Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, fluconazole‐resistant Candida albicans, MTT assay, HeLa cancer cell, MCF‐7 cancer cell, Ag     

One‐pot green synthesis and structural characterisation of silver nanoparticles using aqueous leaves extract of Carissa carandas : antioxidant,anticancer and antibacterial activities

Facile green synthesis of silver nanoparticles (AgNPs) using an aqueous extract of Carissa carandas (C. carandas) leaves was studied. Fabrication of AgNPs was confirmed by the UV–visible spectroscopy which gives absorption maxima at 420 nm. C. carandas leaves are the rich source of the bioactive molecules, acts as a reducing and stabilising agent in AgNPs, confirmed by Fourier transforms infrared spectroscopy. The field emission scanning electron microscope revealed the spherical shape of biosynthesised AgNPs. A distinctive peak of silver at 3 keV was determined by energy dispersive X‐ray spectroscopy. X‐ray diffraction showed the facecentred cubic structure of biosynthesised AgNPs and thermal stability was confirmed by the thermogravimetric analysis. Total flavonoid and total phenolic contents were evaluated in biosynthesised AgNPs. Biosynthesised AgNPs showed free radical scavenging activities against 2, 2‐diphenyl‐1‐picrylhydrazyl test and ferric reducing antioxidant power assay. In vitro cytotoxicity against hepatic cell lines (HUH‐7) and renal cell lines (HEK‐293) were also assessed. Finally, biosynthesised AgNPs were scrutinised for their antibacterial activity against methicillin‐resistant Staphylococcus aureus, Shigella sonnei, Shigella boydii and Salmonella typhimurium. This study demonstrated the biofabrication of AgNPs by using C. carandas leaves extract and a potential in vitro biological application as antioxidant, anticancer and antibacterial agents.Inspec keywords: antibacterial activity, biomedical materials, cancer, tumours, nanomedicine, silver, nanoparticles, reduction (chemical), nanofabrication, ultraviolet spectra, visible spectra, field emission scanning electron microscopy, Fourier transform infrared spectra, X‐ray chemical analysis, X‐ray diffraction, thermal stability, thermal analysis, free radical reactions, toxicology, cellular biophysics, microorganismsOther keywords: total phenolic contents, free radical scavenging activities, 2,2‐diphenyl‐1‐picrylhydrazyl test, ferric reducing antioxidant power assay, in vitro cytotoxicity, hepatic cell lines HUH‐7, renal cell lines HEK‐293, antibacterial activity, methicillin‐resistant Staphylococcus aureus, Shigella sonnei, Shigella boydii, Salmonella typhimurium, biofabrication, in vitro biological application, Ag, total flavonoid contents, thermogravimetric analysis, thermal stability, face‐centred cubic structure, X‐ray diffraction, energy dispersive X‐ray spectroscopy, distinctive peak, spherical shape, field emission scanning electron microscope, Fourier transforms infrared spectroscopy, stabilising agent, reducing agent, bioactive molecules, absorption maxima, UV‐visible spectroscopy, plant extract colour, antibacterial activities, anticancer activities, antioxidant activities, Carissa carandas, aqueous leaves extract, silver nanoparticles, structural characterisation, one‐pot green synthesis     

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     

Antibacterial activity of carbon nanoparticles isolated from chimney soot

Carbon nanoparticles (CNPs) are isolated from chimney soot and characterised by various tools such as X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and ultraviolet–visible spectroscopy. The X‐ray diffraction studies confirm the presence of C₆₀ nanoparticles in the isolated sample. The thermal properties of the prepared CNPs are recorded using thermogravimetric analysis and differential thermal analysis. The analysis of the antibacterial activity of the synthesised CNPs against selected Gram‐positive and Gram‐negative bacterial strains is also investigated. The systematic study confirms that CNPs collected from chimney soot exhibit good antibacterial potency against Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, and Proteus mirabilis.Inspec keywords: ultraviolet spectra, scanning electron microscopy, visible spectra, differential thermal analysis, thermal analysis, antibacterial activity, nanoparticles, X‐ray diffraction, nanofabrication, transmission electron microscopy, carbonOther keywords: chimney soot, transmission electron microscopy, ultraviolet–visible spectroscopy, thermal properties, thermogravimetric analysis, differential thermal analysis, antibacterial activity, carbon nanoparticles, X‐ray diffraction study, gram‐positive bacterial strains, gram‐negative bacterial strains, antibacterial potency, scanning electron microscopy, C₆₀      

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     

Green synthesis of nanosilver‐decorated graphene oxide sheets

A green facile method has been successfully used for the synthesis of graphene oxide sheets decorated with silver nanoparticles (rGO/AgNPs), employing graphite oxide as a precursor of graphene oxide (GO), AgNO₃ as a precursor of Ag nanoparticles (AgNPs), and geranium (Pelargonium graveolens) extract as reducing agent. Synthesis was accomplished using the weight ratios 1:1 and 1:3 GO/Ag, respectively. The synthesised nanocomposites were characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, UV‐visible spectroscopy, Raman spectroscopy, energy dispersive X‐ray spectroscopy and thermogravimetric analysis. The results show a more uniform and homogeneous distribution of AgNPs on the surface of the GO sheets with the weight ratio 1:1 in comparison with the ratio 1:3. This eco‐friendly method provides a rGO/AgNPs nanocomposite with promising applications, such as surface enhanced Raman scattering, catalysis, biomedical material and antibacterial agent.Inspec keywords: silver, nanoparticles, graphene, nanocomposites, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X‐ray diffraction, ultraviolet spectra, visible spectra, X‐ray chemical analysis, surface enhanced Raman scattering, catalysis, nanofabricationOther keywords: antibacterial agent, biomedical material, catalysis, surface enhanced Raman scattering, rGO‐AgNP nanocomposite, eco‐friendly method, homogeneous distribution, thermogravimetric analysis, energy dispersive X‐ray spectroscopy, Raman spectroscopy, UV‐visible spectroscopy, X‐ray diffraction, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, nanocomposites, reducing agent, geranium, graphene oxide sheets, graphite oxide, silver nanoparticles, green facile method     

Differential antibacterial response exhibited by graphene nanosheets toward gram‐positive bacterium Staphylococcus aureus

Two different morphological forms of graphene nanosheets: improved reduced graphene oxide (IRGO) and modified reduced GO (rGO) (MRGO) have been synthesised by improved and modified methods, respectively. Physical characterisations of these graphene nanosheets were carried out using X‐ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Colloidal stability of these nanosheets toward a selected bacterium (e.g. Staphylococcus aureus) was ascertained by zeta potential. In the present study, the authors for the first time made an attempt to study and compare the potentialities of these two different forms of graphene nanosheets as efficient bactericidal agents. Field‐emission scanning electron microscopy and TEM with energy dispersive X‐ray spectroscopy (EDAX) studies of IRGO and MRGO have been carried out to explore their underlying mechanism of antibacterial responses through physical as well as chemical interactions with the selected bacterial species.Inspec keywords: scanning electron microscopy, X‐ray diffraction, graphene, Raman spectra, field emission electron microscopy, microorganisms, colloids, X‐ray chemical analysis, antibacterial activity, electrokinetic effects, nanofabrication, Fourier transform infrared spectra, nanobiotechnologyOther keywords: graphene nanosheets, differential antibacterial response, gram‐positive bacterium, reduced graphene oxide, Staphylococcus aureus, X‐ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, colloidal stability, field‐emission scanning electron microscopy, TEM, EDAX, C     

Facile phyto‐mediated synthesis of silver nanoparticles using Chinese winter jujube (Ziziphus jujuba Mill. cv. Dongzao) extract and their antibacterial/catalytic properties

The aqueous extract of Chinese winter jujube (Ziziphus jujuba Mill. cv. Dongzao) was used as reducing and capping agents for the synthesis of silver nanoparticles (AgNPs) for the first time. The resulting AgNPs were characterised by UV/Visible (UV–Vis) spectroscopy, atomic force microscope, transmission electron microscopy, selected area electron diffraction, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray and Fourier transform infrared spectroscopy (FTIR). The colloidal solution of AgNPs gave a maximum UV–Vis absorbance at 446 nm. The synthesised nanoparticles were almost in the spherical shapes with an average size of 11.5 ± 4. 8 nm. FTIR spectra were applied to identify the functional groups which were possibly responsible for the conversion of metal ions into nanoparticles. The results showed that the prepared AgNPs were coated with the biomolecules in the extract. The biosynthesised AgNPs showed a remarkable catalytic activity at room temperature, and they also showed good antibacterial properties against Escherichia coli and Staphylococcus aureus.Inspec keywords: silver, nanoparticles, nanofabrication, antibacterial activity, biomedical materials, nanobiotechnology, scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, ultraviolet spectra, visible spectra, X‐ray chemical analysis, Fourier transform infrared spectra, catalysisOther keywords: wavelength 446 nm, temperature 293 K to 298 K, Ag, Escherichia coli, Staphylococcus aureus, biomolecules, catalytic activity, metal ions, colloidal solution, FTIR spectra, UV‐vis absorbance, TEM, SEM, XRD, Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, scanning electron microscopy, X‐ray diffraction, selected area electron diffraction, transmission electron microscopy, atomic force microscopy, UV‐visible spectroscopy, catalytic properties, antibacterial properties, Chinese winter jujube extract, silver nanoparticles, facile phyto‐mediated synthesis     

Biosynthesis of γ ‐Fe2 O3 @CuO core–shell nanoclusters using aqueous extract of Sesbania grandiflora Linn fresh leaves,its characterisation,and antimicrobial activity studies against Staphylococcus aureus strains

The present study reports an eco‐friendly and rapid method for the synthesis of core–shell nanoclusters using the modified reverse micelle method. It is a green synthetic method which uses Sesbania grandiflora Linn extract which acts as a reducing and capping agent. It is observed that this method is very fast and convenient and the nanoclusters are formed with 5–10 min of the reaction time without using harsh conditions. The core–shell nanoclusters so prepared were characterised using UV–Vis spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Further, their effective antibacterial activity towards the gram‐positive bacteria Staphylococcus aureus was found to be due to their smaller particle size.Inspec keywords: iron compounds, copper compounds, nanoparticles, particle size, nanofabrication, nanomedicine, biomedical materials, core‐shell nanostructures, antibacterial activity, ultraviolet spectra, visible spectra, microorganisms, reduction (chemical), scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectraOther keywords: biosynthesis, γ‐Fe₂ O₃ ‐CuO core‐shell nanoclusters, aqueous extract, Sesbania grandiflora Linn fresh leaves, antimicrobial activity, Staphylococcus aureus strains, eco‐friendly method, modified reverse micelle method, green synthetic method, reducing agent, capping agent, UV‐visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, antibacterial activity, gram‐positive bacteria Staphylococcus aureus, particle size, time 5 min to 10 min, Fe₂ O₃ ‐CuO     

Silver nanoparticles biosynthesised using Centella asiatica leaf extract: apoptosis induction in MCF‐7 breast cancer cell line

The aim of this study was to green synthesised silver nanoparticles (AgNPs) using Centella asiatica leaf extract and investigate the cytotoxic and apoptosis‐inducing effects of these nanoparticles in MCF‐7 breast cancer cell line. The characteristics and morphology of the green synthesised AgNPs were evaluated using transmission electron microscopy, scanning electron microscopy, UV–visible spectroscopy, X‐ray diffraction, and Fourier‐transform infrared spectroscopy. The MTT assay was used to investigate the anti‐proliferative activity of biosynthesised nanoparticles in MCF‐7 cells. Apoptosis test was performed using flow cytometry and expression of caspase 3 and 9 genes. The spherical AgNPs with an average size of 19.17 nm were synthesised. The results showed that biosynthesised AgNPs exhibited cytotoxicity, anti‐cancer, apoptosis induction, and increased expression of genes encoding for caspases 3 and 9 in MCF‐7 cancer cells in a concentration‐ and time‐dependent manner. It seems that green synthesised AgNPs have potential uses for pharmaceutical industries.Inspec keywords: ultraviolet spectra, transmission electron microscopy, cellular biophysics, infrared spectra, visible spectra, nanofabrication, cancer, toxicology, nanomedicine, nanoparticles, biomedical materials, scanning electron microscopy, silver, Fourier transform spectra, X‐ray diffraction, genetics, enzymes, botany, biochemistryOther keywords: spherical AgNPs, biosynthesised AgNPs, anti‐cancer, apoptosis induction, green synthesised AgNPs, MCF‐7 breast cancer cell line, green synthesised silver nanoparticles, Ag, caspase gene expression, flow cytometry, anti‐proliferative activity, MTT assay, pharmaceutical industries, cytotoxicity, UV–visible spectroscopy, nanoparticle morphology, scanning electron microscopy, Centella asiatica leaf extract, biosynthesised nanoparticles, Fourier‐transform infrared spectroscopy, transmission electron microscopy     

Synthesis,characterisation and bactericidal effect of ZnO nanoparticles via chemical and bio‐assisted (Silybum marianum in vitro plantlets and callus extract) methods: a comparative study

Currently, the evolution of green chemistry in the synthesis of nanoparticles (NPs) with the usage of plants has captivated a great response. In this study, in vitro plantlets and callus of Silybum marianum were exploited as a stabilising agent for the synthesis of zinc oxide (ZnO) NPs using zinc acetate and sodium hydroxide as a substitute for chemical method. The contemporary investigation defines the synthesis of ZnO NPs prepared by chemical and bio‐extract‐assisted methods. Characterisation techniques such as X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and energy dispersive X‐ray were used to confirm the synthesis. Although chemical and bio‐assisted methods are suitable choices for NPs synthesis, the bio‐assisted green assembly is advantageous due to superior stability. Moreover, this report describes the antibacterial activity of the synthesised NPs against standard strains of Klebsiella pneumonia and Bacillus subtilis.Inspec keywords: zinc compounds, II‐VI semiconductors, wide band gap semiconductors, nanoparticles, nanofabrication, semiconductor growth, antibacterial activity, X‐ray diffraction, X‐ray chemical analysis, scanning electron microscopy, Fourier transform infrared spectra, nanobiotechnologyOther keywords: chemical methods, bio‐assisted methods, Silybum marianum in vitro plantlets methods, Silybum marianum in vitro callus extract methods, green chemistry, zinc oxide nanoparticles, sodium hydroxide, zinc acetate, X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, energy dispersive X‐ray analysis, bio‐assisted green assembly, antibacterial activity, Klebsiella pneumonia, Bacillus subtilis, ZnO     

Evaluation of antibacterial property of hydroxyapatite and zirconium oxide‐modificated magnetic nanoparticles against Staphylococcus aureus and Escherichia coli

In the first section of this research, superparamagnetic nanoparticles (NPs) (Fe₃ O₄) modified with hydroxyapatite (HAP) and zirconium oxide (ZrO₂) and thereby Fe₃ O₄ /HAP and Fe₃ O₄ /ZrO₂ NPs were synthesised through co‐precipitation method. Then Fe₃ O₄ /HAP and Fe₃ O₄ /ZrO₂ NPs characterised with various techniques such as X‐ray photoelectron spectroscopy, X‐ray diffraction, scanning electron microscopy, energy dispersive X‐ray analysis, Brunauer–Emmett–Teller, Fourier transform infrared, and vibrating sample magnetometer. Observed results confirmed the successful synthesis of desired NPs. In the second section, the antibacterial activity of synthesised magnetic NPs (MNPs) was investigated. This investigation performed with multiple microbial cultivations on the two bacteria; Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Obtained results proved that although both MNPs have good antibacterial properties, however, Fe₃ O₄ /HAP NP has greater antibacterial performance than the other. Based on minimum inhibitory concentration and minimum bactericidal concentration evaluations, S. aureus bacteria are more sensitive to both NPs. These nanocomposites combine the advantages of MNP and antibacterial effects, with distinctive merits including easy preparation, high inactivation capacity, and easy isolation from sample solutions by the application of an external magnetic field.Inspec keywords: nanocomposites, X‐ray chemical analysis, microorganisms, magnetic particles, scanning electron microscopy, precipitation (physical chemistry), nanomagnetics, X‐ray diffraction, X‐ray photoelectron spectra, nanoparticles, superparamagnetism, iron compounds, antibacterial activity, biomedical materials, nanomedicine, calcium compounds, nanofabrication, Fourier transform infrared spectra, magnetometers, zirconium compoundsOther keywords: antibacterial effects, antibacterial property, superparamagnetic nanoparticles, X‐ray photoelectron spectroscopy, X‐ray diffraction, X‐ray analysis, antibacterial activity, bactericidal concentration, S. aureus bacteria, Staphylococcus aureus, Escherichia coli, hydroxyapatite, coprecipitation method, scanning electron microscopy, energy dispersive X‐ray analysis, Brunauer‐Emmett‐Teller method, Fourier transform infrared spectroscopy, vibrating sample magnetometer, microbial cultivations, nanocomposites     

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     

Antioxidant,antibacterial and anticancer properties of phyto ‐ synthesised Artemisia quttensis Podlech extract mediated AgNPs

The focus of this study is on a rapid and cost‐effective approach for the synthesis of silver nanoparticles (AgNPs) using Artemisia quttensis Podlech aerial parts extract and assessment of their antioxidant, antibacterial and anticancer activities. The prepared AgNPs were determined by ultraviolet–visible spectroscopy, X‐ray diffraction, Fourier transform infra‐red spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, and dynamic light scattering and zeta‐potential analysis. The AgNPs and A. quttensis extract were evaluated for their antiradical scavenging activity by 2, 2‐diphenyl, 1‐picryl hydrazyl assay and anticancer activity against colon cancer (human colorectal adenocarcinoma cell line 29) compared with normal human embryonic kidney (HEK293) cells. Also, the prepared AgNPs were studied for its antibacterial activity. The AgNPs revealed a higher antioxidant activity compared with A. quttensis extract alone. The phyto‐synthesised AgNPs and A. quttensis extract showed a dose–response cytotoxicity effect against HT29 and HEK293 cells. As evidenced by Annexin V/propidium iodide staining, the number of apoptotic HT29 cells was significantly enhanced, following treatment with AgNPs as compared with untreated cells. Besides, the antibacterial property of the AgNPs indicated a significant effect against the selected pathogenic bacteria. These present obtained results show the potential applications of phyto‐synthesised AgNPs using A. quttensis aerial parts extract.Inspec keywords: nanoparticles, silver, nanomedicine, cancer, transmission electron microscopy, ultraviolet spectroscopy, visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, electrokinetic effects, kidney, cellular biophysics, antibacterial activity, toxicology, patient treatmentOther keywords: anticancer properties, antibacterial properties, antioxidant properties, phytosynthesised Artemisia quttensis Podlech extract mediated AgNP, ultraviolet‐visible spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy‐dispersive spectroscopy, dynamic light scattering, zeta‐potential analysis, antiradical scavenging activity, 2,2‐diphenyl, 1‐picryl hydrazyl assay, anticancer activity, HT29 colon cancer, human embryonic kidney cells, HEK293 cells, A. quttensis extract, dose‐response cytotoxicity effect, Annexin V staining, apoptotic HT29 cells, pathogenic bacteria, propidium iodide staining, Ag