Biosynthesis and characterisation of nano‐silica as potential system for carrying streptomycin at nano‐scale drug delivery

A growing trend within nanomedicine has been the fabrication of self‐delivering supramolecular nanomedicines containing a high and fixed drug content ensuring eco‐friendly conditions. This study reports on green synthesis of silica nanoparticles (Si‐NPs) using Azadirachta indica leaves extract as an effective chelating agent. X‐ray diffraction analysis and Fourier transform‐infra‐red spectroscopic examination were studied. Scanning electron microscopy analysis revealed that the average size of particles formed via plant extract as reducing agent without any surfactant is in the range of 100–170 nm while addition of cetyltrimethyl ammonium bromide were more uniform with 200 nm in size. Streptomycin as model drug was successfully loaded to green synthesised Si‐NPs, sustain release of the drug from this conjugate unit were examined. Prolong release pattern of the adsorbed drug ensure that Si‐NPs have great potential in nano‐drug delivery keeping the environment preferably biocompatible, future cytotoxic studies in this connection is helpful in achieving safe mode for nano‐drug delivery.Inspec keywords: silicon compounds, nanofabrication, nanomedicine, drug delivery systems, nanoparticles, X‐ray diffraction, Fourier transform infrared spectra, scanning electron microscopyOther keywords: nanosilica, streptomycin, nanoscale drug delivery, nanomedicine, silica nanoparticles, Azadirachta indica leaves extract, X‐ray diffraction analysis, Fourier transform‐infrared spectroscopy, scanning electron microscopy, cetyltrimethyl ammonium bromide, SiO₂      

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     

Removal of toxic contaminants from water by sustainable green synthesised non‐toxic silver nanoparticles

The study describes the synthesis of silver nanoparticles using 21 different plant extracts having medicinal properties. Molecular ultraviolet‐visible spectroscopy shows that the λ _max of nanoparticles synthesised by different plant extracts varied and ranged between 400 and 468 nm. The ultraviolet results revealed that although synthesis of nanoparticles occurred by all plant extracts successfully, their size varies, this was further confirmed by differential light scattering. The synthesised nanoparticles were investigated for their antimicrobial properties. The most promising silver nanoparticles Ocimum sanctum and Artemisia annua assisted were further characterised using transmission electron microscopy and energy dispersive X‐ray spectroscopy (EDX). EDX data confirms that synthesised nanoparticles are highly pure. Further these two plant assisted nanoparticles were studied for chemocatalytic and adsorptive properties. The silver nanoparticles from Ocimum sanctum can catalyse the reduction of 4‐nitrophenol (63%) within 20 min in the presence of NaBH₄, whereas Artemisia annua assisted silver nanoparticles did not show significant chemocatalytic activity. Both the promising nanoparticles can efficiently adsorb textile dyes from aqueous solutions. These synthesised nanoparticles were also exploited to remove microbial and other contaminants from Yamuna River water. The nanoparticles show excellent antimicrobial properties and can be reused repeatedly.Inspec keywords: antibacterial activity, nanofabrication, silver, dyes, light scattering, visible spectra, microorganisms, X‐ray diffraction, transmission electron microscopy, X‐ray chemical analysis, catalysis, nanoparticles, ultraviolet spectra, adsorption, reduction (chemical)Other keywords: sustainable green synthesised nontoxic silver nanoparticles, silver nitrate, molecular ultraviolet–visible spectroscopy, plant assisted nanoparticles, plant extracts, Ocimum sanctum, Artemisia annua, E. coli, C. albicans, plasmon absorbance, differential light scattering, energy dispersive X‐ray spectroscopy, 4‐nitrophenol, chemocatalytic activity, Yamuna River water, antimicrobial properties, time 20.0 min, time 5.0 min to 240.0 hour, size 1.0 nm to 5.0 nm, size 5.0 nm to 20.0 nm, wavelength 400.0 nm to 468.0 nm, NaBH₄ , Ag     

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     

Green synthesis of copper oxide nanoparticles and mosquito larvicidal activity against dengue,zika and chikungunya causing vector Aedes aegypti

In the present study, high purity copper oxide nanoparticles (NPs) were synthesised using Tridax procumbens leaf extract. Green syntheses of nano‐mosquitocides rely on plant compounds as reducing and stabilising agents. Copper oxide NPs were characterised using X‐ray diffraction (XRD) analysis, Fourier transform infrared (FT‐IR), Field‐emission scanning electron microscopy with energy dispersive spectroscopy, Ultraviolet–visible spectrophotometry and fluorescence spectroscopy. XRD studies of the NPs indicate crystalline nature which was perfectly matching with a monoclinic structure of bulk CuO with an average crystallite size of 16 nm. Formation of copper oxide NPs was confirmed by FT‐IR studies and photoluminescence spectra with emission peaks at 331, 411 and 433 nm were assigned to a near‐band‐edge emission band of CuO in the UV, violet and blue region. Gas chromatography–mass spectrometry studies inferred the phytochemical constituents of the leaf extract. Larvicidal activity of synthesised NPs using T. procumbens leaf extract was tested against Aedes aegypti species (dengue, chikungunya, zika and yellow fever transmit vector).Inspec keywords: photoluminescence, spectrophotometry, thermal analysis, chromatography, nanoparticles, antibacterial activity, field emission electron microscopy, microorganisms, wide band gap semiconductors, scanning electron microscopy, X‐ray diffraction, copper compounds, ultraviolet spectra, nanofabrication, X‐ray chemical analysis, crystallites, visible spectra, field emission scanning electron microscopy, nanobiotechnology, semiconductor materials, semiconductor growth, fluorescence, mass spectraOther keywords: energy dispersive spectroscopy, ultraviolet–visual spectrophotometry, fluorescence spectroscopy, chikungunya, green synthesis, mosquito larvicidal activity, zika, X‐ray diffraction analysis, field‐emission scanning electron microscopy, XRD, gas chromatography–mass spectrometry, copper oxide nanoparticles, dengue, tridax procumben leaf extract, nanomosquitocides, FTIR, monoclinic structure, crystallite size, photoluminescence spectra, near‐band‐edge emission band, phytochemical constituents, Aedes aegypti species, yellow fever transmit vector, CuO     

Photo‐inactivation of bacteria in hospital effluent via thiolated iron‐doped nanoceria

Hospital wastewater is a major contributor of disease‐causing microbes and the emergence of antibiotic resistant bacteria. In this study, thiolated iron‐doped nanoceria was synthesised and tested for killing of microbes from hospital effluent. These particles were designed to inhibit the efflux pumps of the bacteria found in hospital effluent with further ability to activate in visible light via iron doping thus generating tunable amount of reactive oxygen species (ROS). The quantum yield of the ROS generated by the nanoceria was 0.67 while the ROS types produced were singlet oxygen (36%), hydroxyl radical (31%) and hydroxyl ions (32%), respectively. The particles were initially synthesised through green route using Foeniculum vulgare seeds extract and were annealed at 200°C and further coated with thiolated chitosan to enhance the solubility and efflux pump inhibition. X‐ray diffraction confirmed the polycrystalline nature of nanoparticles and uniform spherical shape with 30 nm size, confirmed by scanning electron microscope. The nanoparticles exhibited 100% bactericidal activity at 100 µg/mL against all the isolated bacteria. The enhanced bactericidal effect of iron‐doped nanoceria could be attributed to efflux inhibition via thiolated chitosan as well as the production of ROS upon illumination in visible light, causing oxidative stress against microbes found in hospital effluent.Inspec keywords: health and safety, chemical engineering, solubility, renewable materials, annealing, hospitals, antibacterial activity, cerium compounds, nanoparticles, photochemistry, wastewater treatment, iron, nanofabrication, microorganisms, X‐ray diffraction, effluents, scanning electron microscopy, particle size, diseasesOther keywords: antibiotic resistant bacteria, thiolated iron‐doped nanoceria, hospital effluent, visible light, reactive oxygen species, hydroxyl ions, thiolated chitosan, solubility, efflux pump inhibition, disease‐causing microbes, wastewater treatment, singlet oxygen, hydroxyl radical, Foeniculum vulgare seeds extract, annealing process, X‐ray diffraction, scanning electron microscopy, particle size, bactericidal activity, oxidative stress, photoinactivation, size 30.0 nm, temperature 200.0 degC, CeO₂ :Fe     

Biogenic gold nanoparticles for reduction of 4‐nitrophenol to 4‐aminophenol: an eco‐friendly bioremediation

The present study investigated the synthesis of gold nanoparticles (AuNPs) using mangrove plant extract from Avicennia marina as bioreductant for eco‐friendly bioremediation of 4‐nitrophenol (4‐NP). The AuNPs synthesised were confirmed by UV spectrum, transmission electron microscopy (TEM), X‐ray diffraction, Fourier transmission infrared spectroscopy (FTIR), dynamic light scattering (DLS), and zeta potential. The AuNPs were found to be spherical in shape with size ranging from 4 to 13 nm, as evident by TEM and DLS. Further, the AuNPs were encapsulated with sodium alginate in the form of gold nano beads and used as heterogeneous catalyst and degrading agent to reduce 4‐NP. This reduction in 4‐NP into 4‐aminophenol was confirmed by UV and FTIR. The aqueous solution of 4‐NP peaked its absorbance at 320 nm, and shifted to 400 nm, with an intense yellow colour, appeared due to formation of 4‐nitrophenolate ion. After the addition of AuNps, the 4‐NP solution became colourless and peaked at 400 nm and reduced to 290 nm corresponding to the formation of 4‐aminophenol. Hence, the present work suggested the AuNPs as the potent, eco‐friendly bionanocomposite catalyst for bioremediation of 4‐NP.Inspec keywords: gold, nanoparticles, nanobiotechnology, nanofabrication, ultraviolet spectra, transmission electron microscopy, X‐ray diffraction, Fourier transform spectra, infrared spectra, electrokinetic effects, catalysts, nanocomposites, biochemistryOther keywords: biogenic gold nanoparticles, 4‐nitrophenol, 4‐aminophenol, eco‐friendly bioremediation, mangrove plant extract, Avicennia marina, bioreductant, UV spectrum, transmission electron microscopy, TEM, X‐ray diffraction, Fourier transmission infrared spectroscopy, FTIR, dynamic light scattering, DLS, zeta potential, degrading agent, 4‐nitrophenolate, bionanocomposite catalyst, size 4 nm to 13 nm, wavelength 400 nm, wavelength 290 nm, Au     

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     

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     

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     

Synergistic evaluation of AgO2 nanoparticles with ceftriaxone against CTXM and blaSHV genes positive ESBL producing clinical strains of Uro‐pathogenic E. coli

The silver oxide nanoparticles (AgO₂ ‐NPs) were synthesised using silver foil as a new precursor in wet chemical method. X‐ray diffraction analysis shows crystallographic structures of AgO₂ ‐NPs with crystallite size of 35.54 nm well‐matched with standard cubic structure. Scanning electron microscopy analysis clearly shows the random distribution of spherical‐shaped nanoparticles. Energy dispersive X‐ray analysis confirmed the purity of the samples as it shows no impurity element. Fourier transforms infra‐red analysis confirmed the formation of AgO₂ ‐NPs with the presence of Ag‐O‐Ag stretching bond. All the techniques also confirmed the loading of ceftriaxone drug on the surface of AgO₂ ‐NPs. This study also described the effect of AgO₂ ‐NPs having synergistic activity with β lactam antibiotic i.e. ceftriaxone against ESBL generating Escherichia coli (E. coli). Among isolated strains of E. coli, 60.0% were found to be ESBL producer. The synergistic activities of AgO₂ ‐NPs with ceftriaxone suggest that these combinations are effective against MDR‐ESBL E. coli strains as evident by increase in zone sizes. The present study observed rise in MDR‐ESBL E. coli with polymorphism of blaCTXM and blaSHV causing UTI infections in Pakistani population. The antibiotic and AgO₂ ‐NPs synergistic effect can be used as an efficient approach to combat uro‐pathogenic infections.Inspec keywords: antibacterial activity, nanofabrication, nanomedicine, drugs, nanoparticles, microorganisms, crystallites, scanning electron microscopy, silver compounds, X‐ray diffraction, X‐ray chemical analysis, Fourier transform infrared spectra, organic compounds, geneticsOther keywords: synergistic evaluation, clinical strains, silver oxide nanoparticles, silver foil, wet chemical method, X‐ray diffraction analysis, crystallographic structures, standard cubic structure, spherical‐shaped nanoparticles, energy dispersive X‐ray analysis, ceftriaxone drug, synergistic activity, ESBL producer, scanning electron microscopy, Fourier transform infrared analysis, Escherichia coli, blaSHV gene positive ESBL, crystallite size, random distribution, β lactam antibiotics, MDR‐ESBL E. coli strains, polymorphism, blaCTXM, uro‐pathogenic infections, uro‐pathogenic E. coli, AgO₂      

Green preparation of seaweed‐based silver nano‐liquid for cotton pathogenic fungi management

Silver nanoparticles (Ag NPs) were synthesised using the crude ethyl acetate extracts of Ulva lactuca and evaluated their bioefficacy against two crop‐damaging pathogens. The sets of lattice planes in the XRD spectrum for the Ag NPs were indexed to the 111, 200, 220 and 311 orientations and support the crystalline nature of the Ag NPs. The 3414 and 2968 cm⁻¹ peaks were observed in crude algal thallus extract and they were characteristic of terpenoids. Further, a peak at 1389 cm⁻¹ was observed as fatty acids. The marine macroalgae terpenoids and palmitic acid acted as reducing agent and stabiliser, respectively. The size (3 and 50 nm) and shape (spherical) of Ag NPs were recorded. The energy‐dispersive X‐ray spectroscopy analysis exemplified the presence of silver in its elemental nature. Moreover, U. lactuca Ag NPs were effective against two cotton phytopathogens namely Fusarium oxysporum f.sp. vasinfectum (FOV) and Xanthomonas campestris pv. malvacearum (XAM). The minimum inhibitory concentration was found to be 80.0 and 43.33 μg ml⁻¹ against FOV and XAM, respectively. Results confirmed the anti‐microbial activity of green nanoparticles against select pathogens and suggest their possible usage in developing antifungal agents for controlling destructive pathogens in a cotton agroecosystem.Inspec keywords: nanoparticles, biotechnology, antibacterial activity, silver, microorganisms, X‐ray chemical analysis, crops, X‐ray diffraction, cottonOther keywords: crude ethyl acetate extracts, crop‐damaging pathogens, lattice planes, XRD spectrum, crystalline nature, crude algal thallus, fatty acids, marine macroalgae terpenoids, palmitic acid, energy‐dispersive X‐ray spectroscopy analysis, elemental nature, cotton phytopathogens, green nanoparticles, destructive pathogens, cotton agroecosystem, green preparation, seaweed‐based silver nanoliquid, cotton pathogenic fungi management, silver nanoparticles, Ag NP, Ag     

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     

Phyto‐mediated synthesis,biological and catalytic activity studies of gold nanoparticles

In the present study, a phyto‐mediated synthesis of gold nanoparticles (AuNPs) using an isoflavone, Dalspinosin (5,7‐dihydroxy‐6,3′,4′‐trimethoxy isoflavone) isolated from the alcoholic extract of roots of Dalbergia coromandeliana is reported. It is observed that Dalspinosin itself acts both as a reducing and a capping agent in the synthesis of the nanoparticles (NPs). An ultraviolet–visible (UV–Vis) spectral study showed a surface plasmon resonance band at 526 nm confirming the formation of AuNPs. The NPs formed were characterised by UV–Vis spectroscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction (XRD), high‐resolution transmission electron microscopy (HR‐TEM) with energy‐dispersive x‐ray spectroscopy (EDX) and dynamic light scattering. HR‐TEM analysis showed the synthesised AuNPs were spherical in shape with a size of 7.5 nm. The AuNPs were found to be stable for seven months when tested by in vitro methods showed good antioxidant and anti‐inflammatory activities. They also showed moderate anti‐microbial activities when tested against Gram positive (Staphylococcus aureus and Streptococcus sp), Gram negative bacterial strains (Klebsiella pneumonia and Klebsiella terrigena) and fungal strain (Candida glabrata). The biosynthesised AuNPs showed significant catalytic activity in the reduction of methylene blue with NaBH₄ to leucomethylene blue.Inspec keywords: biomedical materials, catalysis, Fourier transform infrared spectra, gold, light scattering, microorganisms, nanomedicine, nanoparticles, spectrochemical analysis, surface plasmon resonance, transmission electron microscopy, ultraviolet spectra, visible spectra, X‐ray chemical analysis, X‐ray diffractionOther keywords: phyto‐mediated synthesis, biological activity studies, catalytic activity studies, dalspinosin (5,7‐dihydroxy‐6,3′,4′‐trimethoxy isoflavone), alcoholic extract, roots, Dalbergia coromandeliana, ultraviolet‐visible spectral study, surface plasmon resonance band, UV‐Vis spectroscopy, Fourier transform‐infrared spectroscopy, X‐ray diffraction, high‐resolution transmission electron microscopy, EDX analysis, dynamic light scattering, HR‐TEM analysis, antioxidant activities, antiinflammatory activities, antimicrobial activities, Gram positive bacterial strains, Staphylococcus aureus, Streptococcus sp, Gram negative bacterial strains, wavelength 526 nm, size 7.5 nm, time 7 month, Au     

Solvothermal‐assisted green synthesis of hybrid Chi‐Fe3 O4 nanocomposites: a potential antibacterial and antibiofilm material

In this present study, a hybrid Chi‐Fe₃ O₄ was prepared, characterised and evaluated for its antibacterial and antibiofilm potential against Staphylococcus aureus and Staphylococcus marcescens bacterial pathogens. Intense peak around 260 nm in the ultraviolet–visible spectrum specify the formation of magnetite nanoparticles. Spherical‐shaped particles with less agglomeration and particle size distribution of 3.78–46.40 nm were observed using transmission electron microscopy analysis and strong interaction of chitosan with the surface of magnetite nanoparticles was studied using field emission scanning microscopy (FESEM). X‐ray diffraction analysis exhibited the polycrystalline and spinel structure configuration of the nanocomposite. Presence of Fe and O, C and Cl elements were confirmed using energy dispersive X‐ray microanalysis. Fourier transform infrared spectroscopic analysis showed the reduction and formation of Chi‐Fe₃ O₄ nanocomposite. The antibacterial activity by deformation of the bacterial cell walls on treatment with Chi‐Fe₃ O₄ nanocomposite and its interaction was visualised using FESEM and the antibiofilm activity was determined using antibiofilm assay. In conclusion, this present study shows the green synthesis of Chi‐Fe₃ O₄ nanocomposite and evaluation of its antibacterial and antibiofilm potential, proving its significance in medical and biological applicationsInspec keywords: visible spectra, particle size, magnetic particles, nanocomposites, nanoparticles, X‐ray diffraction, nanofabrication, transmission electron microscopy, X‐ray chemical analysis, nanomagnetics, microorganisms, antibacterial activity, iron compounds, ultraviolet spectra, biomedical materials, field emission scanning electron microscopy, Fourier transform infrared spectra, filled polymers, crystal growth from solution, polymer structureOther keywords: potential antibacterial material, antibiofilm potential, magnetite nanoparticles, solvothermal‐assisted green synthesis, hybrid Chi‐Fe₃ O₄ nanocomposites, staphylococcus aureus, staphylococcus marcescens, bacterial pathogens, ultraviolet–visible spectrum, spherical‐shaped particles, particle size, transmission electron microscopy, FESEM, field emission scanning electron microscopy, X‐ray diffraction, spinel structure, polycrystalline structure, energy dispersive X‐ray microanalysis, Fourier transform infrared spectroscopic analysis, deformation, bacterial cell walls, Fe₃ O₄      

Hypnea musciformis‐mediated Ag/AgCl‐NPs inhibit pathogenic bacteria,HCT‐116 and MCF‐7 cells’ growth in vitro and Ehrlich ascites carcinoma cells in vivo in mice

In the present study, Ag/AgCl‐NPs were biosynthesised using Hypnea musciformis seaweed extract; NPs synthesis was confirmed by a change of colour and observation of a razor‐sharp peak at 424 nm by UV–visible spectroscopy. Synthesised nanoparticles were characterised by transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray powder diffraction and Fourier transform infrared spectroscopy. Bacterial cell growth inhibition proves that the Ag/AgCl‐NPs have strong antibacterial activity and cell morphological alteration was observed in treated bacterial cells using propidium iodide (PI). Ag/AgCl‐NPs inhibited Ehrlich ascites carcinoma (EAC) cells, colorectal cancer (HCT‐116) and breast cancer (MCF‐7) cell line in vitro with the IC₅₀ values of 40.45, 24.08 and 36.95 μg/ml, respectively. Initiation of apoptosis in HCT‐116 and MCF‐7 cells was confirmed using PI, FITC‐annexin V and Hoechst 33342 dye. No reaction oxygen species generation was observed in both treated and untreated cell lines. A significant increase of ATG‐5 gene expression indicates the possibility of autophagy cell death besides apoptosis in MCF‐7 cells. The initiation of apoptosis in EAC cells was confirmed by observing caspase‐3 protein expression. Ag/AgCl‐NPs inhibited 22.83% and 51% of the EAC cell growth in vivo in mice when administered 1.5 and 3.0 mg/kg/day (i.p.), respectively, for 5 consequent days.     

Structural and physicochemical properties of Rheum emodi mediated Mg(OH)2 nanoparticles and their antibacterial and cytotoxic potential

In the present investigation, Rheum emodi roots extract mediated magnesium hydroxide nanoparticles [Mg(OH)₂ NPs] through the bio‐inspired experimental technique were synthesised. Mg(OH)₂ NPs were characterised by using various characterisation techniques such as field emission scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet–visible spectroscopy. The formation of Mg(OH)₂ NPs was confirmed by X‐ray diffraction. The structural analysis confirmed the hexagonal crystal symmetry of Mg(OH)₂ NPs with space group P‐3m1 and space group no. 164 using the Rietveld refinement technique. TEM micrographs illustrated the nano‐size formation of Mg(OH)₂ NPs of spherical shape and size ∼14.86 nm. With the aid of FTIR data, plant metabolites such as anthraquinones have been identified as a stabilising and reducing agent for the synthesis of biogenic Mg(OH)₂ NPs. The synthesised Mg(OH)₂ NPs showed antimicrobial and cytotoxic potential against Gram‐negative and Gram‐positive bacteria such as Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) and MDA‐MB‐231 human breast cancer cell lines.Inspec keywords: antibacterial activity, microorganisms, visible spectra, cancer, X‐ray diffraction, cellular biophysics, nanomedicine, ultraviolet spectra, nanoparticles, transmission electron microscopy, nanofabrication, field emission scanning electron microscopy, Fourier transform infrared spectra, particle size, magnesium compounds, space groups, toxicologyOther keywords: physicochemical properties, structural properties, Rheum emodi root extract mediated magnesium hydroxide nanoparticles, bio‐inspired experimental technique, field emission scanning electron microscopy, transmission electron microscopy, TEM, Fourier transform infrared spectroscopy, FTIR spectroscopy, ultraviolet‐visible spectroscopy, X‐ray diffraction, hexagonal crystal symmetry, space group P‐3m1, space group no. 164, Rietveld refinement technique, nanosize formation, plant metabolites, spherical shape, antibacterial potential, cytotoxic potential, reducing agent, anthraquinones, stabilising agent, Gram‐positive bacteria, Gram‐negative bacteria, Escherichia coli, Staphylococcus aureus, MDA‐MB‐231 human breast cancer cell lines, Mg(OH)₂      

Inhibitory effect of TiO2 NPs on symbiotic arbuscular mycorrhizal fungi in plant roots

While nanoparticles (NPs) are known to exhibit antimicrobial properties, their effects on symbiotic arbuscular mycorrhizal fungi (AMF) in plant roots has to be carefully examined as NPs particularly of titanium dioxide (TiO₂) reach plant roots through varied sources such as fertilisers, plant protection products and other nanoproducts. The objective of the present study is to assess the effect of TiO₂ NPs on the symbiotic behaviour of AMF colonising rice (Oryza sativa L.) plants. Using sol–gel method, TiO₂ NPs with three different sizes were successfully synthesised employing doping. Characterisation of the prepared material was done by X‐ray powder diffraction and scanning electron microscopy. The synthesised materials were applied at 0, 25, 50 and 100 mg plant–1 to the rhizosphere of mycorrhizal rice plants maintained in pots. The study revealed that the prepared NPs had an inhibitory effect on arbuscular mycorrhizal symbiosis in plant roots. Development of AMF structures such as vesicles and arbuscules was significantly reduced in TiO₂ ‐doped NPs with a relatively more inhibition in 2% TiO₂ ‐doped NPs. Among the concentrations of TiO₂ NPs applied to different treatments, %F was significantly (P < 0.001) affected at medium to higher levels of application.Inspec keywords: nanoparticles, titanium compounds, antibacterial activity, sol‐gel processing, X‐ray diffraction, scanning electron microscopy, microorganisms, cellular biophysics, nanomedicineOther keywords: symbiotic arbuscular mycorrhizal fungi, plant roots, nanoparticles, antimicrobial properties, fertilisers, plant protection, nanoproducts, AMF colonising rice, sol‐gel method, X‐ray powder diffraction, scanning electron microscopy, mycorrhizal rice plants, rhizosphere, arbuscular mycorrhizal symbiosis, soil biota, TiO₂      

Microbicidal activity of TiO2 nanoparticles synthesised by sol–gel method

In this study, the authors investigated antimicrobial activity of TiO₂ nanoparticles (NPs) synthesised by sol–gel method. As synthesised TiO₂ NPs were characterised by X‐ray diffraction, scanning electron microscopy and ultraviolet‐visible absorption spectroscopy. The antimicrobial activity of calcined TiO₂ nanoparticle samples was examined in day light on Gram positive bacteria (Staphylococcus aureus, Streptococcus pneumonia and Bacillus subtilis), Gram negative bacteria (Proteus vulgaris, Pseudomonas aeruginosa and Escherichia coli) and fungal test pathogen Candida albicans. The synthesised TiO₂ NPs were found to be effective in visible light against Streptococcus pneumonia, Staphylococcus aureus, Proteus vulgaris, Pseudomonas aeruginosa and Candida albicans.Inspec keywords: titanium compounds, microorganisms, nanomedicine, biomedical materials, nanofabrication, sol‐gel processing, ultraviolet spectra, visible spectra, X‐ray diffraction, scanning electron microscopy, nanoparticles, antibacterial activityOther keywords: microbicidal activity, titanium dioxide nanoparticle, sol‐gel method, antimicrobial activity, X‐ray diffraction, scanning electron microscopy, ultraviolet‐visible absorption spectroscopy, Gram positive bacteria, Staphylococcus aureus, Streptococcus pneumonia, Bacillus subtilis, TiO₂ , Candida albicans, fungal test pathogen, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Gram negative bacteria     

Biosynthesis of Selenium Nanoparticles using yeast Nematospora coryli and examination of their anti‐candida and anti‐oxidant activities

Selenium (Se) is a rare and essential element for the human body and other living organisms because of its role in the structure of several proteins and having anti‐oxidant properties to reduce oxidative stress at cells. Some microorganisms can absorb Se oxyanions and convert them into zero‐valent Se (Se0) in the nanoscale dimensions, which can be used for producing Se nanoparticles (SeNPs). In the present study, SeNPs were intracellularly biosynthesised by yeast Nematospora coryli, which is an inexpensive method and does not involve using materials hazardous for human and environment. The produced NPs were refined by a two‐phase system and then characterised and identified by ultraviolet–visible, X‐ray diffraction, X‐ray fluorescence, transmission electron microscope, and Fourier transform infrared spectroscopy analyses. The structural analysis of biosynthesised SeNPs showed spherical‐shaped NPs with size ranging from 50 to 250 nm. Also, extracted NPs were applied to explore their anti‐candida and anti‐oxidant activities. The results of this investigation confirm the biological properties of Se.Inspec keywords: X‐ray diffraction, microorganisms, oxidation, transmission electron microscopy, reduction (chemical), nanomedicine, biomedical materials, visible spectra, nanoparticles, proteins, nanofabrication, selenium, ultraviolet spectra, particle size, Fourier transform infrared spectra, antibacterial activityOther keywords: proteins, oxidative stress, Se oxyanions, yeast, biosynthesised SeNPs, anti‐oxidant activities, human body, living organisms, Se nanoparticles, Nematospora coryli, anti‐candida activities, biosynthesis, ultraviolet–visible analysis, X‐ray diffraction, X‐ray fluorescence, transmission electron microscope, Fourier transform infrared spectroscopy, structural analysis, size 50.0 nm to 250.0 nm, Se