Biogenic synthesis,characterisation and antifungal activity of gum kondagogu‐silver nano bio composite construct: assessment of its mode of action

The biogenic synthesis of silver nanoparticles was achieved by using gum kondagogu (Cochlospermum gossypium), a natural biopolymer (Gk‐AgNPs). Synthesised nanoparticles were characterised by using UV–visible spectroscopy, inductively coupled plasma‐atomic emission spectrometer, X‐ray diffraction, transmission electron microscope techniques. The silver nano particle size determined was found to be 3.6 ± 2.2 nm. The synthesised Gk‐AgNPs showed antifungal activity and exhibited minimum inhibitory concentration and minimal fungicidal concentration values ranging from 3.5 to 6.5 µg mL⁻¹ against Aspergillus parasiticus (NRRL‐2999) and Aspergillus flavus (NRRL‐6513). Scanning electron microscopy–energy dispersive spectroscopy analysis revealed morphological changes including deformation, shrunken and ruptured mycelium of the fungi. At the biochemical level, the mode of action revealed that there was an elevated level of reactive oxygen species, lipid peroxidation, superoxide dismutase, and catalase enzyme activity. Increased oxidative stress led to increased outer membrane damage, which was confirmed by the entry of N ‐phenyl naphthylamine to the phospholipid layer of outer membrane and higher levels of K⁺ release from the fungi treated with Gk‐AgNPs. This study explores the possible application of biogenic silver nanoparticles produced from gum kondagogu as potent antifungal agents. The potent antifungal activity of Gk‐AgNPs gives scope for its relevance in biomedical application and as a seed dressing material.Inspec keywords: antibacterial activity, nanocomposites, silver, nanofabrication, nanoparticles, biomedical materials, polymers, visible spectra, ultraviolet spectra, atomic emission spectroscopy, X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, microorganisms, X‐ray chemical analysis, enzymes, lipid bilayers, biomembranes, biomechanics, nanomedicineOther keywords: antifungal activity, gum kondagogu‐silver nanobiocomposite, Cochlospermum gossypium, natural biopolymer, UV‐visible spectroscopy, inductively coupled plasma‐atomic emission spectrometer, X‐ray diffraction, transmission electron microscope, fungicidal concentration, Aspergillus parasiticus, Aspergillus flavus, scanning electron microscopy, SEM‐energy dispersive spectroscopy, fungi deformation, ruptured mycelium, reactive oxygen species, lipid peroxidation, superoxide dismutase, catalase enzyme activity, oxidative stress, membrane damage, N‐phenyl naphthylamine, phospholipid layer, potassium ion release, biogenic silver nanoparticle, antifungal agent, seed dressing material, Ag     

FSE–Ag complex NS: preparation and evaluation of antibacterial activity

Silver (Ag) complexes of drugs and their nanosystems have great potential as antibacterials. Recently, an Ag complex of furosemide (Ag–FSE) has shown to be a promising antimicrobial. However, poor solubility of Ag–FSE could hamper its introduction into clinics. Therefore, the authors developed a nanosuspension of Ag–FSE (Ag–FSE_NS) for its solubility and antibacterial activity enhancement. The aim of this study was to introduce a novel nanoantibiotic with enhanced antibacterial efficacy. Ag–FSE_NS was prepared by precipitation–ultrasonication technique. Size, polydispersity index (PI) and zeta potential (ZP) of prepared Ag–FSE_NS were measured by dynamic light scattering, whereas surface morphology was determined using scanning electron microscopy (SEM). In vitro antibacterial activity was evaluated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa using broth microdilution method. Size, PI and ZP of optimised Ag–FSE_NS1 were 191.2 ± 19.34 nm, 0.465 ± 0.059 and −55.7 ± 8.18 mV, respectively. SEM revealed that Ag–FSE_NS1 particles were rod or needle‐like with smooth surfaces. Saturation solubility of Ag–FSE in NS increased eight‐fold than pure Ag–FSE. Ag–FSE_NS1 exhibited two‐fold and eight‐fold enhancements in activity against E. coli and S. aureus, respectively. The results obtained showed that developed Ag–FSE_NS1 holds a promise as a topical antibacterial.Inspec keywords: nanomedicine, nanofabrication, light scattering, surface morphology, silver, particle size, solubility, suspensions, scanning electron microscopy, electrokinetic effects, drugs, biomedical materials, antibacterial activity, microorganisms, nanoparticles, drug delivery systems, transmission electron microscopyOther keywords: saturation solubility, topical antibacterial, size 171.86 nm to 210.54 nm, voltage ‐47.52 mV to ‐63.88 mV, Ag, broth microdilution method, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, SEM, scanning electron microscopy, surface morphology, dynamic light scattering, particle size, polydispersity index, precipitation–ultrasonication technique, nanoantibiotic, nanosuspension, furosemide, nanosystems, drugs, Ag–FSE_NS preparation, in vitro antibacterial activity, pure Ag–FSE, Ag–FSE_NS1 particles, optimised Ag–FSE_NS1, zeta potential, enhanced antibacterial efficacy, antibacterials     

Characterisation of sol–gel method synthesised MgZnFe2 O4 nanoparticles and its cytotoxic effects on breast cancer cell line,MDA MB‐231 in vitro

In this study, nanocrystalline magnesium zinc ferrite nanoparticles were successfully prepared by a simple sol–gel method using copper nitrate and ferric nitrate as raw materials. The calcined samples were characterised by differential thermal analysis/thermogravimetric analysis, Fourier transform infrared spectroscopy and X‐ray diffraction. Transmission electron microscopy revealed that the average particle size of the calcined sample was in a range of 17–41 nm with an average of 29 nm and has spherical size. A cytotoxicity test was performed on human breast cancer cells (MDA MB‐231) and (MCF‐7) at various concentrations starting from (0 µg/ml) to (800 µg/ml). The sample possessed a mild toxic effect toward MDA MB‐231 and MCF‐7 after being examined with MTT (3‐[4, 5‐dimethylthiazol‐2‐yl]‐2, 5 diphenyltetrazolium bromide) assay for up to 72 h of incubation. Higher reduction of cells viability was observed as the concentration of sample was increased in MDA MB‐231 cell line than in MCF‐7. Therefore, further cytotoxicity tests were performed on MDA MB‐231 cell line.Inspec keywords: sol‐gel processing, nanoparticles, nanofabrication, magnesium compounds, zinc compounds, toxicology, biological organs, cancer, cellular biophysics, nanomedicine, calcination, differential thermal analysis, Fourier transform infrared spectra, X‐ray diffraction, transmission electron microscopy, particle size, organic compoundsOther keywords: sol‐gel method, cytotoxic effects, breast cancer cell line, MDA MB‐231 in vitro, nanocrystalline magnesium zinc ferrite nanoparticles, copper nitrate, ferric nitrate, raw materials, calcined samples, differential thermal analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, average particle size, cytotoxicity testing, human breast cancer cells, mild toxic effect, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyltetrazolium bromide) assay, cell viability, MCF‐7, MDA MB‐231 cell line, size 17 nm to 41 nm     

Synthesis of biotin‐targeted chitosan/poly (methyl vinyl ether‐alt ‐maleic acid) copolymeric micelles for delivery of doxorubicin

Biotinylated chitosan/poly(methyl vinyl ether‐alt ‐maleic acid) (PMVEMA) copolymer was synthesised by an amide reaction in two steps. Structural characterisation was performed using ¹ HNMR and Fourier transform infra‐red (FTIR) spectra. Critical micelle concentration (CMC) of the copolymer was determined by pyrene as a fluorescent probe. Doxorubicin (DOX) was loaded in the micelles by the direct dissolution method. The effects of different variables including type of copolymer, copolymer concentration, stirring rate and stirring time were studied on the physicochemical properties of the micelles including: particle size, zeta potential, release efficiency and loading efficiency of nanoparticles using an irregular factorial design. The in vitro cytotoxicity of DOX‐loaded biotin‐targeted micelles was studied in HepG2 cells which over express biotin receptors by 3, 5‐[dimethylthiazol‐2‐yl]‐2, 5‐diphenyl tetrazolium bromide assay. The successful synthesis of the biotinylated copolymer of chitosan/PMVEMA was confirmed by FTIR and ¹ HNMR. The optimised micelles showed the CMC of 33 μg/ml, particle size of 247 ± 2 nm, zeta potential of +9.46 mV, polydispersity index of 0.22, drug‐loading efficiency of 71% and release efficiency of 84.5 ± 1.6%. The synthesised copolymer was not cytotoxic. The cytotoxicity of DOX‐loaded in targeted micelles on HepG2 cell line was about 2.2‐fold compared with free drug.Inspec keywords: biomedical materials, cellular biophysics, dissolving, drug delivery systems, drugs, electrokinetic effects, fluorescence, Fourier transform infrared spectra, particle size, polymer blends, spectrochemical analysis, toxicologyOther keywords: ¹ HNMR spectra, biotin‐targeted chitosan‐poly (methyl vinyl ether‐alt‐maleic acid) copolymeric micelles, doxorubicin delivery, amide reaction, structural characterisation, Fourier transform infrared spectra, pyrene, fluorescent probe, direct dissolution method, physicochemical properties, particle size, zeta potential, nanoparticles, irregular factorial design, in vitro cytotoxicity, DOX‐loaded biotin‐targeted micelles, 3, 5‐[dimethylthiazol‐2‐yl]‐2, 5‐diphenyl tetrazolium bromide assay, polydispersity index, drug‐loading efficiency, HepG2 cell line, voltage 9.46 mV     

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     

Green synthesis of CuO nanoparticles loaded on the seashell surface using Rumex crispus seeds extract and its catalytic applications for reduction of dyes

In this study, CuO nanoparticles supported on the seashell (CuO NPs/seashell) was prepared using Rumex crispus seeds extract as a chelating and capping agent. The prepared nanocomposite was characterised by Fourier transform infrared spectroscopy, X‐ray diffraction, field emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and transmission electron microscopy. The particle size of CuO NPs on the seashell sheets was in the range of 8–60 nm. Catalytic ability of CuO NPs/seashell was investigated for the reduction of 4‐nitrophenol (4‐NP) and Congo red (CR). It was observed that catalyst can be easily recovered and reused several times without any significant loss of catalytic efficiency.Inspec keywords: nanocomposites, nanoparticles, catalysis, dyes, Fourier transform infrared spectra, X‐ray diffraction, field emission electron microscopy, scanning electron microscopy, X‐ray chemical analysis, transmission electron microscopy, particle size, copper compoundsOther keywords: CuO, size 8 nm to 60 nm, Congo red, 4‐nitrophenol, particle size, transmission electron microscopy, energy dispersive X‐ray spectroscopy, field emission scanning electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, nanocomposite, capping agent, chelating agent, dye reduction, catalytic application, Rumex crispus seeds extract, seashell surface, nanoparticles, green synthesis     

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     

Cytotoxic potentials of biologically fabricated platinum nanoparticles from Streptomyces sp. on MCF‐7 breast cancer cells

Biosynthesis of novel therapeutic nano‐scale materials for biomedical and pharmaceutical applications has been enormously developed, since last decade. Herein, the authors report an ecological way of synthesising the platinum nanoparticles (PtNPs) using Streptomyces sp. for the first time. The produced PtNPs exhibited the face centred cubic system. The fourier transform infrared spectrum revealed the existence of amino acids in proteins which serves as an essential reductant for the formation of PtNPs. The spherical morphology of the PtNPs with an average size of 20–50 nm was observed from topographical images of atomic force microscopy and field emission scanning electron microscopy. The X‐ray fluorescence spectrum confirms the presence of PtNPs with higher purity. The PtNPs size was further confirmed with transmission electron microscopy analysis and the particles were found to exist in the same size regime. Additionally, PtNPs showed the characteristic surface plasmon resonance peak at 262 nm. Dynamic light scattering studies report that 97.2% of particles were <100 nm, with an average particle diameter of about 45 nm. Furthermore, 3‐(4, 5‐dimethyl‐2‐thiazolyl)‐2, 5‐diphenyl‐tetrazolium assay based in vitro cytotoxicity analysis was conducted for the PtNPs, which showed the inhibitory concentration (IC₅₀) at 31.2 µg/ml against Michigan Cancer Foundation‐7 breast cancer cells.Inspec keywords: biomedical materials, materials preparation, nanoparticles, nanomedicine, nanofabrication, cellular biophysics, microorganisms, cancer, platinum, Fourier transform infrared spectra, proteins, atomic force microscopy, scanning electron microscopy, fluorescence, transmission electron microscopy, surface plasmon resonance, light scatteringOther keywords: cytotoxic potentials, biologically fabricated platinum nanoparticles, Streptomyces sp, MCF‐7 breast cancer cells, biosynthesis, therapeutic nanoscale materials, biomedical applications, pharmaceutical applications, Fourier transform infrared spectrum, amino acids, spherical morphology, topographical images, atomic force microscopy, field emission scanning electron microscopy, X‐ray fluorescence spectrum, transmission electron microscopy analysis, surface plasmon resonance, dynamic light scattering, 3‐(4, 5‐dimethyl‐2‐thiazolyl)‐2, 5‐diphenyl‐tetrazolium assay, cytotoxicity analysis, Pt     

Screening the UV‐blocking and antimicrobial properties of herbal nanoparticles prepared from Aloe vera leaves for textile applications

Nanomaterials play a vital role in textile industries due to their unique properties and applications. There is an increase in the use of nanoscale phyto products in textiles to control the bacterial infection in fabrics. Here, natural herbal nanoparticles of different sizes were prepared from shade‐dried Aloe vera plant leaves using ball milling technique without any additives. The amorphous herbal A. vera nanoparticles possess an average particle size of 40 ± 2 nm and UV‐absorption maximum at 269 nm. A. vera nanopowders–chitosan nanocomposites were prepared and coated on cotton fabrics using pad‐dry cure method. The evaluation of antibacterial activity against Escherichia coli (22.05 ± 0.06 mm) and Staphylococcus aureus (27.17 ± 0.02 mm), UV‐protection properties (UV‐protection factor = 57.2 ± 0.1), and superhydrophobic nature (155 ± 3°) of the prepared herbal nanoparticles and their composites were analysed by disc diffusion, UV–visible spectral analysis, and contact angle analysis. Understanding the functional properties of herbal nanoparticles, coated particles on fabrics highlights their potential applications in protective clothing with better antimicrobial properties, hydrophobicity, and UV‐protection properties. This study of using A. vera herbal nanoparticles in textiles significantly enhances the fabric performance to develop protective textile fabrics in defence and biomedical fields.Inspec keywords: nanoparticles, particle size, nanofabrication, nanomedicine, antibacterial activity, biomedical materials, hydrophobicity, ultraviolet spectra, visible spectra, radiation protection, textile fibres, cotton fabrics, ball milling, X‐ray diffraction, light scattering, scanning electron microscopy, X‐ray fluorescence analysis, fluorescence, amorphous state, nanocomposites, filled polymers, protective coatings, curing, microorganisms, biodiffusion, contact angle, surface morphology, protective clothingOther keywords: UV‐blocking, antimicrobial properties, disc diffusion, UV‐visible spectral analysis, contact angle analysis, morphological characteristics, protective clothing, protective textile fabrics, biomedical fields, superhydrophobic nature, UV‐protection factor, UV‐protection properties, Staphylococcus aureus, Escherichia coli, pad‐dry cure method, cotton fabrics, A. vera nanopowders‐chitosan nanocomposites, UV‐absorption maximum, average particle size, amorphous herbal A. vera nanoparticles, X‐ray fluorescence spectrometry, scanning electron microscopy, dynamic light scattering, UV‐visible spectrophotometry, X‐ray diffraction, ball milling, shade‐dried Aloe vera plant leaves, natural herbal nanoparticle size, bacterial infection, nanoscale phyto products, textile industries, nanomaterials, textile applications     

Role of catalytic protein and stabilising agents in the transformation of Ag ions to nanoparticles by Pseudomonas aeruginosa

Biological routes of synthesising metal nanoparticles (NPs) using microbes have been gaining much attention due to their low toxicity and eco‐friendly nature. Pseudomonas aeruginosa JP2 isolated from metal contaminated soil was evaluated towards extracellular synthesis of silver NPs (AgNPs). Cell‐free extract (24 h) of the bacterial isolate was reacted with AgNO₃ for 24 h in order to fabricate AgNPs. Preliminary observations were recorded in terms of colour change of the reaction mixture from yellow to greyish black. UV‐visible spectroscopy of the reaction mixture has shown a progressive increase in optical densities that correspond to peaks near 430 nm, depicting reduction of ionic silver (Ag⁺) to atomic silver (Ag⁰) thereby synthesising NPs. X‐ray diffraction spectra exhibited the 2θ values to be 38.4577° confirming the crystalline and spherical nature of NPs [9.6 − 26.7 (Ave. = 17.2 nm)]. Transmission electron microscopy finally confirmed the size of the particles varying from 5 to 60 nm. Moreover, rhamnolipids and proteins were identified as stabilising molecules for the AgNPs through Fourier transform‐infrared spectroscopy. Characterisation of bacterial crude and purified protein fractions confirmed the involvement of nitrate reductase (molecular weight 66 kDa and specific activity = 3.8 U/mg) in the Synthesis of AgNPs.Inspec keywords: microorganisms, silver, nanoparticles, enzymes, molecular biophysics, ultraviolet spectra, visible spectra, X‐ray diffraction, transmission electron microscopy, Fourier transform infrared spectra, catalysis, biochemistry, nanobiotechnologyOther keywords: catalytic protein, stabilising agents, Pseudomonas aeruginosa, metal nanoparticles, UV–visible spectroscopy, optical densities, ionic silver, atomic silver, X‐ray diffraction spectra, transmission electron microscopy, nitrate reductase, rhamnolipids, Fourier transform‐infrared spectroscopy, Ag     

Biosynthesis of SeNPs by Mycobacterium bovis and their enhancing effect on the immune response against HBs antigens: an in vivo study

Conventional hepatitis B vaccine contains alum but is less effective to induce Th1 response. Selenium nanoparticles and Bacillus Calmette–Guerin were reported as immune modulators. In this study, SeNPs were extracted from Mycobacterium bovis and characterised. SeNPs were mixed with HBs‐Ag and administered to the mice to investigate he immune response pattern. With an addition of Se ions at a sub‐inhibitory concentration to the Sauton medium broth after 24 h, SeNPs were extracted from M. bovis and characterised by Fourier transform infrared spectroscopy, dynamic light scattering, atomic forcemicroscopy, energy dispersive X‐ray spectrum, transmission electron microscopy, and thermogravimetric analysis. Furthermore, female inbred BALB/c mice were injected subcutaneously on the first, 14th, 28th day with 100 and 200 µg doses of that SeNPs supplemented with HBs‐Ag vaccine. Later, the total antibody, isotypes of Immunoglobulin G1, Interlukin 4, and interferon‐γ were measured by enzye‐linked immunosorbent assay. The size of the SeNPs was <150 nm. Level of total antibody and immunoglobulin G2a increased significantly in the group that received 200 µg/ml nano selenium extracted from M. bovis. SeNPs in dose of 200 µg coated with organic materials of M. bovis could induce an influential immune response in relation to the conventional HBs‐Ag vaccine.Inspec keywords: selenium, nanoparticles, nanofabrication, microorganisms, Fourier transform spectra, infrared spectra, light scattering, atomic force microscopy, X‐ray chemical analysis, transmission electron microscopy, thermal analysis, nanomedicineOther keywords: biosynthesis, selenium nanoparticles, Mycobacterium bovis, enhnced immune response, HBs antigens, Bacillus Calmette‐Guerin, immune modulators, biogenic SeNPs, immune response pattern, Sauton medium broth, Fourier transform infrared spectroscopy, dynamic light scattering, atomic force microscopy, energy dispersive X‐ray spectrum, transmission electron microscopy, thermogravimetric analysis, female inbred BALB/c mice, antibody, IgG1 isotype, IgG2a isotype, IL₄ isotype, interferon‐γ, enzyme‐linked immunosorbent assay, bacterium, time 24 h, time 14 day, time 28 day, Se     

Phyto‐assisted synthesis of bio‐functionalised silver nanoparticles and their potential anti‐oxidant,anti‐microbial and wound healing activities

Bio‐ synthesis of silver nanoparticles (AgNPs) was made by using the aqueous leaf extract of Ardisia solanacea. Rapid formation of AgNPs was observed from silver nitrate upon treatment with the aqueous extract of A. solanacea leaf. The formation and stability of the AgNPs in the colloidal solution were monitored by UV–visible spectrophotometer. The mean particle diameter of AgNPs was calculated from the DLS with an average size ∼4 nm and ∼65 nm. ATR‐FTIR spectroscopy confirmed the presence of alcohols, aldehydes, flavonoids, phenols and nitro compounds in the leaf which act as the stabilizing agent. Antimicrobial activity of the synthesized AgNPs was performed using agar well diffusion and broth dilution method against the Gram‐positive and Gram‐negative bacteria. Further, robust anti‐oxidative potential was evaluated by DPPH assay. The highest antimicrobial activity of synthesized AgNPs was found against Pseudomonas aeruginosa (28.2 ± 0.52 mm) whereas moderate activity was found against Bacillus subtilis (16.1 ± 0.76), Candida kruseii (13.0 ± 1.0), and Trichophyton mentagrophytes (12.6 ± 1.52). Moreover, the potential wound healing activity was observed against the BJ‐5Ta normal fibroblast cell line. Current research revealed that A. solanacea was found to be a suitable source for the green synthesis of silver nanoparticles.Inspec keywords: antibacterial activity, nanoparticles, silver, nanomedicine, wounds, microorganisms, X‐ray diffraction, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopyOther keywords: phyto‐assisted synthesis, biofunctionalised silver nanoparticles, antioxidant antimicrobial wound healing activities, silver nanoparticle biosynthesis, aqueous leaf extract, Ardisia solanacea, silver nitrate, UV–visible spectroscopy, dynamic light scattering, Fourier transform infra‐red spectroscopy, X‐ray diffraction, electron microscopy, attenuated total reflection Fourier transform infra‐red spectroscopy, dilution method, Gram‐positive bacteria, Gram‐negative bacteria, radical scavenging method, Pseudomonas aeruginosa, Trichophyton mentagrophytes, Bacillus subtilis, Candida kruseii, BJ‐5Ta normal fibroblast cell line, SEM, alcohols, aldehydes, flavonoids, phenols, nitro compounds, Ag     

Bacteriogenic synthesis of selenium nanoparticles by Escherichia coli ATCC 35218 and its structural characterisation

A biosynthetic method for the production of selenium nanoparticles under ambient temperature and pressure from sodium selenite was developed using Gram‐negative bacterial strain Escherichia coli ATCC 35218. Bacteriogenic nanoparticles were methodologically characterized employing UV‐vis, XRD, Raman spectroscopy, SEM, TEM, DLS and FTIR techniques. Generation of nanoparticles was visualized from the appearance of red colour in the selenite supplemented culture medium and broad absorption bands in the UV‐vis. Biofabricated nanoparticles were spherical, polydisperse, ranged from 100‐183 nm and the average particle size was about 155 nm. Based on selected‐area electron diffraction, XRD patterns; and Raman spectroscopy the nanospheres were found to be amorphous. IR spectrum revealed the involvement of bacterial proteins in the reduction of selenite and stabilization of nanoparticles. Used bacterial strain demonstrated efficient selenite reduction capability which was evident from 89.2% of selenium removal within 72 h at a concentration of 1 mM. Observation noted in the current study highlight the importance of bacterial reduction in selenium nanoparticle generation which can be scaled up for commercial production. Also, the bacteriogenic, amorphous nanoparticles can also be used as nutritional supplements for humans since selenium nanoparticles of 5‐200 nm are bioavailable and known to induce seleno enzymes involved in antioxidant defence.Inspec keywords: Fourier transform infrared spectra, transmission electron microscopy, scanning electron microscopy, electron diffraction, ultraviolet spectra, microorganisms, X‐ray diffraction, nanofabrication, Raman spectra, visible spectra, nanoparticles, particle size, seleniumOther keywords: bacteriogenic synthesis, selenium nanoparticles, Escherichia coli ATCC 35218, structural characterisation, biosynthetic method, gram negative bacterial strain, UV–visible spectroscopy, X‐ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, particle size, selected area electron diffraction, bacteriological reduction, seleno enzymes, size 100 nm to 183 nm, Se     

Docetaxel‐loaded solid lipid nanoparticles: a novel drug delivery system

Over the past few years, taxanes have emerged as a new class of anticancer drugs. Docetaxel (DTX) the prototype of this class has been approved for the treatment of broad range of cancers. However, to date the commercial preparation of DTX (Taxotere^®) is accompanying adverse side effects, intolerance, and poor solubility, which can be overcome by encapsulating them using solid lipid nanoparticles (SLNs). SLNs represent versatile delivery system of drugs with newer forms such as polymer–solid lipid hybrid, surface modified and long circulating nanoparticles bringing forth improved prospects for cancer chemotherapy. In this review, the authors have discussed the current uses of various SLNs formulations of DTX with key emphasis on controlled and site‐specific drug delivery along with enhanced antitumour activity elucidated via in vitro and in vivo studies. Furthermore, the review article highlights few approaches that can be used in combination with existing DTX‐loaded SLNs to supplement DTX drug delivery.Inspec keywords: nanoparticles, nanomedicine, drug delivery systems, biomedical materials, cancer, reviews, tumoursOther keywords: docetaxel‐loaded solid lipid nanoparticles, drug delivery system, taxanes, anticancer drugs, Taxotere, SLN encapsulation, polymer‐solid lipid hybrid, surface modified nanoparticles, long circulating nanoparticles, chemotherapy, review     

Comparative study of antifungal effect of green and chemically synthesised silver nanoparticles in combination with carbendazim,mancozeb, and thiram

This study reports synthesis and characterisation of silver nanoparticles and their effect on antifungal efficacy of common agricultural fungicides. Silver nanoparticles were synthesised using biological and chemical reduction methods employing Elettaria cardamomum leaf extract and sodium citrate, respectively. Nanoparticles were then characterised using UV–Visible spectroscopy, X‐ray diffraction (XRD), transmission electron microscopy, and dynamic light scattering (DLS). While XRD assigned particles size of 31.86 nm for green and 41.91 nm for chemical silver nanoparticles with the help of the Debye–Scherrer formula, DLS specified monodisperse nature of both suspensions. Nanoparticles were tested individually and in combination with fungicides (carbendazim, mancozeb, and thiram) against fungal phytopathogens. Silver nanoparticles exhibited good antifungal activity and minimum inhibitory concentration (MIC) was observed in the range of 8–64 µg/ml. Also, they positively influenced the efficacy of fungicides. The mean MIC value (mean ± SD) for combination of all three fungicides with green AgNPs was 1.37 ± 0.6 µg/ml and for chemical AgNPs was 1.73 ± 1.0 µg/ml. Hence, it could be concluded that green AgNPs performed better than chemical AgNPs. Synergy was observed between green AgNPs and fungicides against Fusarium oxysporum. In conclusion, this study reports synthesis of monodisperse silver nanoparticles which serve as efficient antifungal agents and also enhance the fungicidal action of reported agricultural fungicides in combination studies.Inspec keywords: X‐ray diffraction, reduction (chemical), visible spectra, ultraviolet spectra, microorganisms, particle size, nanomedicine, nanofabrication, nanoparticles, agrochemicals, antibacterial activity, transmission electron microscopy, silver, light scattering, scanning electron microscopyOther keywords: antifungal effect, green silver nanoparticles, chemically synthesised silver nanoparticles, carbendazim, mancozeb, thiram, antifungal efficacy, common agricultural fungicides, biological reduction methods, chemical reduction methods, transmission electron microscopy, XRD assigned particles size, chemical silver nanoparticles, green AgNPs, chemical AgNPs, monodisperse silver nanoparticles, antifungal activity, agricultural fungicides, Elettaria cardamomum leaf extract, sodium citrate, UV‐visible spectroscopy, X‐ray diffraction, dynamic light scattering, size 31.86 nm, size 41.91 nm     

Nigella sativa oil entrapped polycaprolactone nanoparticles for leishmaniasis treatment

This study is the first to investigate the antileishmanial activities of Nigella sativa oil (NSO) entrapped poly‐ɛ ‐caprolactone (PCL) nanoparticles on Leishmania infantum promastigotes and amastigotes in vitro. NSO molecules with variable initial doses of 50, 100, 150, and 200 mg were successfully encapsulated into PCL nanoparticles identified as formulations NSO1, NSO2, NSO3, and NSO4, respectively. This process was characterised by scanning electron microscope, dynamic light scattering, Fourier transform infrared, encapsulation efficiency measurements, and release profile evaluations. The resulting synthetised nanoparticles had sizes ranging between 200 and 390 nm. PCL nanoparticles encapsulated 98% to 80% of initial doses of NSO and after incubation released approximately 85% of entrapped oil molecules after 288 h. All investigated formulations demonstrated strong antileishmanial effects on L. infantum promastigotes by inhibiting up to 90% of parasites after 192 h. The tested formulations decreased infection indexes of macrophages in a range between 2.4‐ and 4.1‐fold in contrast to control, thus indicating the strong anti‐amastigote activities of NSO encapsulated PCL nanoparticles. Furthermore, NSO‐loaded PCL nanoparticles showed immunomodulatory effects by increasing produced nitric oxide amounts within macrophages by 2–3.5‐fold in contrast to use of free oil. The obtained data showed significant antileishmanial effects of NSO encapsulated PCL nanoparticles on L. infantum promastigotes and amastigotes.Inspec keywords: antibacterial activity, drug delivery systems, nanofabrication, nitrogen compounds, nanomedicine, microorganisms, cellular biophysics, diseases, scanning electron microscopy, oils, polymers, biomedical materials, nanoparticles, encapsulation, Fourier transform infrared spectraOther keywords: encapsulation efficiency measurements, entrapped oil molecules, investigated formulations, NSO‐loaded PCL nanoparticles, Nigella sativa oil entrapped polycaprolactone nanoparticles, antileishmanial activities, poly‐ε‐caprolactone nanoparticles, scanning electron microscope, DLS, Fourier transform infrared, release profile evaluations, Leishmania infantum promastigotes, Leishmania infantum amastigotes, parasites, infection, infection indexes, macrophages, immunomodulatory effects, time 288.0 hour, time 192.0 hour, mass 50.0 mg, mass 100.0 mg, mass 150.0 mg, mass 200.0 mg, size 200.0 nm to 390.0 nm     

Antibacterial,anti‐inflammatory and antioxidant effects of acetyl‐11‐α‐keto‐β‐boswellic acid mediated silver nanoparticles in experimental murine mastitis

Mastitis is an important economic disease causing production losses in dairy industry. Antibiotics are becoming ineffective in controlling mastitis due to the emergence of resistant strains requiring the development of novel therapeutic agents. In this study, the authors present the phytochemical synthesis of silver nanoparticles (AgNPs) with acetyl‐11‐α‐keto‐β‐boswellic acid and evaluation of their activity in Staphylococcus aureus induced murine mastitis. Boswellic acid mediated AgNP (BANS) were oval, polydispersed (99.8 nm) with an minimum inhibitory concentration of 0.033 µg ml⁻¹ against S. aureus, inhibitory concentration (IC₅₀) of 30.04 µg ml⁻¹ on mouse splenocytes and safe at an in vivo acute oral dose of 3.5 mg kg⁻¹ in mice. Mastitis was induced in lactating mice by inoculating S. aureus (log₁₀ 5.60 cfu) and treated 6 h post‐inoculation with BANS (0.12 mg kg⁻¹, intramammary and intraperitoneal), and cefepime (1 mg kg⁻¹, intraperitoneal). S. aureus inoculated mice showed increased bacterial load, neutrophil infiltration in mammary glands and elevated C‐reactive protein (CRP) in serum. Oxidative stress was also observed with elevated malondialdehyde level, superoxide dismutase (SOD) and catalase (CAT) activities. BANS treatment significantly (P  < 0.05) reduced bacterial load, CRP, SOD, CAT activities and neutrophil infiltration in affected mammary glands. BANS could be a potential therapeutic agent for managing bovine mastitis.Inspec keywords: nanomedicine, nanoparticles, silver, antibacterial activity, drugs, diseases, enzymesOther keywords: antibacterial effects, antiinflammatory effects, antioxidant effects, acetyl‐11‐α‐keto‐β‐boswellic acid, mediated silver nanoparticles, experimental murine mastitis, economic disease, dairy industry, resistant strains, phytochemical synthesis, Staphylococcus aureus, minimum inhibitory concentration, inoculating S. aureus, neutrophil infiltration, mammary glands, elevated C‐reactive protein, superoxide dismutase, catalase, bovine mastitis, Ag     

Biosynthesis of palladium nanoparticles using Poplar leaf extract and its application in Suzuki coupling reaction

A green route for the synthesis of palladium (Pd) nanoparticles (Pd NPs) employing Poplar leaf extract as a reducing and capping agent is described. The as‐prepared Pd NPs are spherical with a face centred cubic structure, a particle distribution of 2.2–6.8 nm and an average particle size of 4.2 nm. The application of this catalyst toward homogeneous Suzuki coupling reactions was investigated. The Pd NPs afforded a yield of 98.86% in the Suzuki coupling reaction of 4‐bromotoluene with phenylboronic acid using 0.01 mmol% of the catalyst at 60°C for 30 min under an air atmosphere.Inspec keywords: palladium, nanoparticles, nanofabrication, particle size, catalysts, organic compounds, nanobiotechnologyOther keywords: biosynthesis, palladium nanoparticles, Poplar leaf extract, green route, reducing agent, capping agent, face centred cubic structure, particle size, catalyst, homogeneous Suzuki coupling reactions, 4‐bromotoluene, phenylboronic acid, size 4.2 nm, temperature 60 C, Pd     

Facile synthesis of reduced graphene oxide/trimethyl chlorosilane‐coated cellulose nanofibres aerogel for oil absorption

A hydrophobic and oleophilic trimethyl chlorosilane/reduced graphene oxide‐coated cellulose nanofibres (TMCS/rGO/CNFs) aerogel with a three‐dimensional structure was fabricated through a facile dip‐coating process. The prepared aerogel exhibited several advantageous properties for absorption and expulsion of oils from water surfaces, such as a high specific surface area, low density (6.78 mg/cm³) and good porosity (99.12％). In addition, the TMCS/rGO/CNFs aerogel demonstrated good absorption capacities up to 39 times its own weight over a short time (1.5 min) for a broad range of oils. This research suggests that practical application of TMCS/rGO/CNFs aerogel in the cleanup of an oil spill is feasible.Inspec keywords: graphene, nanofibres, aerogels, absorption, hydrophobicity, dip coating, oil pollution, nanofabricationOther keywords: facile synthesis, reduced graphene oxide‐trimethyl chlorosilane‐coated cellulose nanofibre aerogel, three‐dimensional structure, facile dip‐coating process, oil expulsion, water surfaces, TMCS‐rGO‐CNF aerogel, oil absorption capacities, oil spill cleanup, CO     

Mesoporous titanium dioxide nanocatalyst: a recyclable approach for one‐pot synthesis of 5‐hydroxymethylfurfural

The present study deals with the production of 5‐hydroxymethyl furfural (HMF) from fructose by chemo‐conversion method using chemical catalyst, conventionally achieved by microwave‐assisted dehydration process. Five different chemical catalysts, namely oxalic acid, phosphotungstic acid and mesoporous titanium dioxide nanoparticles (TNPs) were compared at constant conditions of which TNPs yielded a maxima of 33.95%. The optimum temperature and catalyst loading were found to be 200°C and 20%, respectively, at a 5% optimum substrate concentration during 15 min optimum reaction time to yield 61.53% HMF. The efficiency of synthesised TNPs was investigated further through reusability studies. TNPs were properly recycled and the catalytic activity recovery was good even after a 14 batch reactions. The specific surface area of the TNP obtained is about 105.46 m² /g and its pore‐volume is about 0.42 cm³ /g according to single point adsorption. A large accessible surface area combined with a minimal pore size (15.92 nm) obtained with mesoporous TNPs is desirable for better catalyst loading, high‐yield HMF, retention and reduced diffusion constraints.Inspec keywords: mesoporous materials, recycling, production management, dissociation, nanoparticles, nanotechnologyOther keywords: mesoporous titanium dioxide nanocatalyst, recyclable approach, one‐pot synthesis, 5‐hydroxymethyl furfural production, HMF, chemo‐conversion method, chemical catalyst, microwave‐assisted dehydration process, oxalic acid, phosphotungstic acid, mesoporous titanium dioxide nanoparticles, TNP