Bio-fabrication of silver nanoparticles by Pseudomonas aeruginosa: optimisation and antibacterial activity against selected waterborne human pathogens
This study has been designed to synthesise AgNPs from Pseudomonas aeruginosa. AgNPs formation was confirmed by colour change and UV–vis spectroscopy. Furthermore, Fourier transform infrared spectroscopy peaks demonstrated the presence of capped proteins as reducing and stabilising agent. Transmission electron microscopy micrograph revealed spherical shape AgNPs with the size ranging between 10 and 20 nm. Antibacterial activity of AgNPs was evaluated against the most prevalent waterborne pathogens enterohaemorrhagic Escherichia coli and Salmonellae typhimurium. Moreover, the antibacterial activity of AgNPs was...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Efficacy of using oxygen microbubble device for facultative anaerobe removal
In this study, the authors conducted simulations with a denture to investigate the efficacy of using this method to remove facultative anaerobes. In this research for the optimal device design, several variables were manipulated including rotation speeds of the bubble generator, different nozzle diameters, and different numbers of nozzle holes. The results revealed that the device is effective in removing facultative anaerobes; moreover, of all design variables, the number of nozzle holes was the factor having the largest effect on anaerobe removal, as it influenced the flow volume and oxygen content of the discharge: the ...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Low-temperature synthesis of hierarchical structures of copper oxide and their superior biological activity
In this work, the authors report a facile low-temperature wet-chemical route to prepare morphology-tailored hierarchical structures (HS) of copper oxide. The preparation of copper oxide collides was carried out using varying concentrations of copper acetate and a reducing agent at a constant temperature of 50°C. The prepared HS of CuO were characterised by powdered X-rays diffraction that indicates phase pure having monoclinic structures. The morphology was further confirmed by field-emission scanning electron microscope. It reveals a difference in shape and size of copper oxide HS by changing the concentration of rea...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
The use of slow releasing nanoparticle encapsulated Azadirachtin formulations for the management of Caryedon serratus O. (groundnut bruchid)
Nanobiotechnology is one of the emerging fields and its interventions in agriculture is been attracting the scientific community. Herein, the authors first to report on control of groundnut bruchid (Caryedon serratus O.) using nanoscale zinc oxide (ZnONPs) particles and nanoscale chitosan (CNPs) particles-based Azadirachtin formulations. ZnONPs and CNPs were prepared using sol–gel and ion tropic gelation techniques, respectively. Neem seed kernel extract (NSKE) 5% and Neem oil (3000 and 1000 ppm) were encapsulated using the prepared nanoscale materials and characterised using the techniques such as dynamic li...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Surface characterisation and reaction kinetics of silver nanoparticles mediated by the leaf and flower extracts of French marigold (Tagetes patula)
In this study, French marigold's leaf and flower were used for the synthesis of silver nanoparticles (SNPs) in order to explore their potentials towards bioreduction of Ag+ to Agᵒ. The as-synthesised SNPs were characterised using UV–Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction, transmission electron microscopy, and zeta-potential analysis. The results obtained showed that the particles are polydispersed with sizes in the range 15.8–42.8 nm. The bioreduction was believed to be due to the amides, aldehyde functional groups, and essential oils present i...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Comparative study on nanostructured order–disorder in the wing eyespots of the giant owl butterfly, Caligo memnon
A characteristic feature of the giant owl butterfly, i.e. Caligo memnon, is its big wing eyespot. This feature could serve as deceiving functionality for the butterfly against predators. As evidenced by scanning electron microscope (SEM) image on black part of eyespot, the scales on wing eyespot contain nanostructured ridges and cross-ribs. Applying direct measurement, statistical method, and Fourier analysis, the authors evidence that these nanostructures display order–disorder in their shape and position. The autocorrelation of SEM image provides average values of characteristic periods of the order–disorde...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Preparation of alginate oligosaccharide nanoliposomes and an analysis of their inhibitory effects on Caco-2 cells
The conditions were optimised for preparing Alginate oligosaccharide (AOS) nanoliposomes, and Caco-2 cell experiments were carried out to examine their antitumour effects. The optimal formulation of AOS nanoliposomes was as follows: a phosphatidylcholine-to-cholesterol ratio of 5.12, AOS concentration of 8.44 mg/mL, Tween 80 concentration of 1.11%, and organic phase to aqueous phase ratio of 5.25. Under the above conditions, the experimental encapsulation efficiency was 65.84%, and the AOS nanoliposomes exhibited a small particle size of 323 nm. After Caco-2 cells were treated with AOS liposomes and AOS for 2...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Biosynthesis of waste pistachio shell supported silver nanoparticles for the catalytic reduction processes
Silver nanoparticles (NPs) are immobilised on pistachio shell surface by Cichorium intybus L. leaves extract as an antioxidant media. The Fourier transform infrared spectra, X-ray diffraction, field-emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, and transmission electron microscope analyses confirmed the support of silver NPs on the pistachio shell (Ag NPs/pistachio shell). Ag NPs on the pistachio shell had a diameter basically in the 10–15 nm range. Reduction reactions of 4-nitrophenol (4-NP), and organic dyes at ambient condition were used in the investigation of t...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Green biosynthesis, characterisation and antimicrobial activities of silver nanoparticles using fruit extract of Solanum viarum
Green synthesis of nanoparticles is considered an efficient method when compared with chemical and physical methods because of its bulk production, eco-friendliness and low cost norms. The present study reports, for the first time, green synthesis of silver nanoparticles (AgNPs) at room temperature using Solanum viarum fruit extract. The visual appearance of brownish colour with an absorption band at 450 nm, as detected by ultraviolet-visible spectrophotometer analysis, confirmed the formation of AgNPs. X-ray diffraction confirmed the AgNPs to be crystalline with a face-centred lattice. The transmission electron mic...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Effect of silver nanoparticles and silver nitrate on growth of rice under biotic stress
This study was organised to check the effect of silver nanoparticles and silver nitrate on rice growth against biotic stress. Silver nanoparticles were synthesised by using plant extract as reducing agent, followed by characterisation through UV Vis spectroscopy, XRD, EDS and SEM. Aspergillus application significantly reduced rice plant fresh mass (0.9%), dry mass (0.21%), root length (2.3%), shoot length (5.2%) and root number (1%) in comparison to control. Similarly, leaf area, leaf fresh mass, dry mass and leaf number were also reduced by 23.1, 0.02, 0.11 and 0.9%, respectively. AgNPs and AgNO3 treatments increased the ...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Role of AgNPs in the enhancement of seed germination and its effect on plumule and radicle length of Pennisetum glaucum
The authors have investigated beneficial effects of 1 mM of silver nanoparticles (AgNPs) on agriculturally important plant Pennisetum glaucum (Bajara). The extracellular AgNPs were synthesised using Bacillus subtilis spizizenni and characterised using ultraviolet–visible absorption spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM). Optical absorption spectrum showed characteristic peak of AgNPs at 423 nm. FT-IR analysis of AgNPs showed peak at 3435 cm−1, which indicates the presence of N–H group (primary, secondary amines and a...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Cu-induced assembly of methanobactin-modified gold nanoparticles and its peroxidase mimic activity
Methanobactin (Mb) is a small copper-chelating molecule that functions as an agent for copper acquisition, uptake and copper-containing methane monooxygenase catalysis in methane-oxidising bacteria. The UV–visible spectral and fluorescence spectral suggested that Mb/Cu coordination complex as a monomer (Mb-Cu), dimmer (Mb2-Cu) and tetramer (Mb4-Cu) could be obtained at different ratios of Mb to Cu (II). The kinetics of the oxidation of hydroquinone with hydrogen peroxide catalysed by the different Mb/Cu coordination complex were investigated. The results suggested that Mb2-Cu coordination form has highest catalytic ...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Facile synthesis of gold nanoparticles using carbon dots for electrochemical detection of neurotransmitter, dopamine in human serum and as a chemocatalyst for nitroaromatic reduction
Herein, the authors reported a carbon dots mediated synthesis of gold nanoparticles (AuNPs) at room temperature. Transmission electron microscopy revealed that the AuNPs are spherical in shape with a size of 10 nm. As-prepared AuNPs was immobilised on carbon paste electrode and subjected to electrochemical sensing of an important neurotransmitter dopamine. Differential pulse voltammetry studies revealed sensitive and selective determination of dopamine in the presence of commonly interfering ascorbic acid and uric acid. The linear detection range was 10–600 μM and the limit of detection was 0.7&#...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Microwave-mediated synthesis of zinc oxide nanoparticles: a therapeutic approach against Malassezia species
A successful protocol was developed to aid in the reduction in dandruff-causing fungi, namely Malassezia globasa and Malassezia furfur. Both the species were isolated from volunteers aged between 20 and 22 suffering from dandruff, cultured ex vivo, and tested against the presence of synthesised zinc oxide nanoparticles (ZnNP). Direct microscopy, scanning electron microscopy (SEM), and biochemical assays specific to Malassezia species were conducted to identify dandruff-causing fungal species. Microwave-mediated synthesis of ZnNP was performed and characterised by UV–vis, X-ray diffraction, and SEM. The nanoparticles...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
Synthesis and characterisation of nanostructured hardystonite coating on stainless steel for biomedical application
Here, nanostructured hardystonite bioceramic (Ca2ZnSi2O7) was synthesised from tetraethyl orthosilicate, zinc nitrate hexahydrate, and calcium nitrate tetrahydrate via sol–gel method, dried at 60–120°C, and finally calcinated at 1300°C. X-ray diffraction (XRD) analysis confirmed the formation of hardystonite bioceramic. Afterwards, electrophoretic method was utilised to coat the hardystonite ceramic on 316L stainless steel (SS). Methanol solution was used as suspension solvent. The best deposition procedure was carried out by electrophoretic device in the voltage of 50 V for 5 min. XRD...
Source: IET Nanobiotechnology - October 4, 2018 Category: Nanotechnology Source Type: research
