Small‐sized probe for local measuring electrical properties of the tissues inside of human body: design,modelling and simulation

In this study, a new idea is suggested for designing an appropriate bio‐impedance probe in the form of a biopsy forceps to measure the electrical properties of the tissues inside the body. First, by analytically solving the Laplace equation for wedge‐shaped tissue in the mouth of the probe, the relationship between electric potential (results from excitation current) in a different point on the tissue and the electrical properties of the tissue is obtained. Then, to evaluate the designed bio‐impedance probe using the finite element method and the experimental data obtained for different tissues by Gabriel et al., modelling and simulation at different frequencies from 50 Hz to 5 MHz were done. Finally, to evaluate the performance of the designed probe in comparison to other methods, measurements were carried out using three methods for the same tissue. Nyquist curves were drawn and electrical properties extracted for all the three methods. It was found that the designed probe results are close to the actual values with an error of <2%. The main features of the designed probe are small size and non‐invasive measurement.Inspec keywords: Laplace equations, biological tissues, finite element analysis, electric impedance measurement, bioelectric potentials, biomedical measurementOther keywords: noninvasive measurement, local measuring electrical properties, human body, wedge‐shaped tissue, electric potential, finite element method, bio‐impedance probe, small‐sized probe, biopsy forceps, excitation current, Nyquist curves, frequency 50.0 Hz to 5.0 MHz     

Design and development of a portable resistive sensor based on α‐MnO2/GQD nanocomposites for trace quantification of Pb(II) in water

The occurrence of heavy metal ions in food chain is appearing to be a major problem for mankind. The traces of heavy metals, especially Pb(II) ions present in water bodies remains undetected, untreated, and it remains in the food cycle causing serious health hazards for human and livestock. The consumption of Pb(II) ions may lead to serious medical complications including multiple organ failure which can be fatal. The conventional methods of heavy metal detection are costly, time‐consuming and require laboratory space. There is an immediate need to develop a cost‐effective and portable sensing system which can easily be used by the common man without any technical knowhow. A portable resistive device with miniaturized electronics is developed with microfluidic well and α‐MnO₂/GQD nanocomposites as a sensing material for the sensitive detection of Pb(II). α‐MnO₂/GQD nanocomposites which can be easily integrated with the miniaturized electronics for real‐time on‐field applications. The proposed sensor exhibited a tremendous potential to be integrated with conventional water purification appliances (household and commercial) to give an indication of safety index for the drinking water. The developed portable sensor required low sample volume (200 µL) and was assessed within the Pb(II) concentration range of 0.001 nM to 1 uM. The Limit of Detection (LoD) and sensitivity was calculated to be 0.81 nM and 1.05 kΩ/nM/mm², and was validated with the commercial impedance analyser. The shelf‐life of the portable sensor was found to be ∼45 days.     

Development of magnetosomes‐based biosensor for the detection of Listeria monocytogenes from food sample

Listeriosis through contaminated food is one of the leading causes of premature deaths in pregnant women and new born babies. Here, the authors have developed a magnetosomes‐based biosensor for the rapid, sensitive, specific and cost‐effective detection of Listeria monocytogenes from food sample. Magnetosomes were extracted from Magnetospirillum sp. RJS1 and then directly bound to anti‐Listeriolysin antibody (0.25–1 µg/ml), confirmed in spectroscopy. Listeriolysin (LLO) protein (0.01–7 µg/ml) was optimised in enzyme‐linked immunosorbent assay. Magnetosomes was conjugated with LLO antibody (0.25 µg/ml) in optimum concentration to detect LLO protein (0.01 µg/ml). Magnetosomes–LLO antibody complex was 25% cost effective. The magnetosomes–LLO antibody complex was directly stabilised on screen printed electrode using external magnet. The significant increase in resistance (R _CT value) on the electrode surface with increase in concentration of LLO protein was confirmed in impedance spectroscopy. The L. monocytogenes contaminated milk and water sample were processed and extracted LLO protein was detected in the biosensor. The specificity of the biosensor was confirmed in cross‐reactivity assay with other food pathogens. The detection limit of 10¹ Cfu/ml in both water and milk sample manifests the sensitive nature of the biosensor. The capture efficiency and field emission scanning electron microscopy confirmed positive interaction of Listeria cells with magnetosomes–antibody complex.Inspec keywords: proteins, food safety, enzymes, contamination, biosensors, dairy products, microorganisms, cost reduction, separation, electrodes, magnets, electric resistance, field emission scanning electron microscopyOther keywords: anti‐Listeriolysin antibody, LLO protein, monocytogenes contaminated milk, food pathogens, magnetosomes‐based biosensor, Listeria monocytogenes, contaminated food, sensitive cost‐effective detection, listeriosis, extraction process, Magnetospirillum sp. RJS1, enzyme‐linked immunosorbent assay, LLO antibody complex, screen printed electrode, magnet, electric resistance, RCT value, electrode surface, impedance spectroscopy, field emission scanning electron microscopy     

Synthesis and characterisation of iron oxide nanoparticles conjugated with epidermal growth factor receptor (EGFR) monoclonal antibody as MRI contrast agent for cancer detection

The aim of this study is to synthesise superparamagnetic iron oxide nanoparticles conjugated with anti‐epidermal growth factor receptor monoclonal antibody (ANTI‐EGFR‐SPION) and investigate its physicochemical characterisation and biocompatibility as a targeted magnetic resonance imaging (MRI) contrast agent for the EGFR‐specific detection in EGFR expressing tumour cells. These particles employed biocompatible polymers, poly(D,L‐lactide‐co‐glycolide) (PLGA) and polyethylene glycol aldehyde (PEG‐aldehyde), to increase the half‐life of particles in circulation and reduce their side effects. The Fe₃ O₄ ‐loaded PLGA‐PEG‐aldehyde nanoparticles were prepared by a modified water‐in‐oil‐in‐water double emulsion method. The EGFR antibody was conjugated to the surface of SPIONs using the aldehyde‐amine reaction. Synthesised conjugates (nanoprobes) were characterised using Fourier transform infrared spectrophotometry, dynamic light scattering, transmission electron microscopy images, and vibrating‐sample magnetometery, and the results showed that the conjugation was successful. The mean diameter of nanoprobes was about 25 nm. These nanoprobes exhibited excellent water‐solubility, stability, and biocompatibility. Meanwhile, MR susceptibility test proved that synthesised nanoprobes can be managed for negative contrast enhancement. The results of this study suggested the potential use of these nanoprobes for non‐invasive molecular MRI in EGFR detection in the future.Inspec keywords: solubility, nanomedicine, cancer, spectrophotometry, emulsions, biomedical MRI, nanomagnetics, nanofabrication, tumours, nanoparticles, magnetic particles, molecular biophysics, light scattering, proteins, cellular biophysics, Fourier transform spectra, superparamagnetism, polymers, transmission electron microscopy, iron compoundsOther keywords: physicochemical characterisation, superparamagnetic iron oxide nanoparticles, novel targeting cancer detection, anti‐epidermal growth factor receptor monoclonal antibody, ANTI‐EGFR‐SPION, biocompatibility, targeted magnetic resonance imaging contrast agent, EGFR‐specific detection, EGFR expressing tumour cells, biocompatible polymers, PLGA‐PEG‐aldehyde nanoparticles, modified water‐in‐oil‐in‐water double emulsion method, EGFR antibody, aldehyde‐amine reaction, synthesised conjugates were characterised using Fourier, transmission electron microscopy images, synthesised nanoprobes, EGFR detection, size 25.0 nm, Fe₃ O₄      

Antibacterial and dye degradation potential of zero‐valent silver nanoparticles synthesised using the leaf extract of Spondias dulcis

The present study reports a simple and low cost synthesis of zero‐valent silver nanoparticles (ZVSNPs) from silver nitrate using the leaf extract of Spondias dulcis. The ZVSNPs showed a unique peak at 420 nm in UV–vis spectrum. The SEM image portrayed cuboidal shaped particles. The EDX spectrum designated the elemental silver peak at 3 keV. In XRD, a sharp peak at 32.47° denoted the existence of (1 0 1) lattice plane and the average crystallite size was calculated as 48.61 nm. The lattice parameter was determined as 0.39 nm. The FTIR spectra of the leaf extract and ZVSNPs showed shifts in the specific functional group bands which ascertained the involvement of phytoconstituents in the formation and capping of nanoparticles. The average hydrodynamic size was measured as 59.66 nm by DLS method. A low PDI, 0.187 witnessed the monodispersity. A negative zeta potential value of −15.7 mV indicated the negative surface charges of the nanoparticles. The bactericidal action of ZVSNPs was demonstrated against two pathogens S.typhimurium and E.coli during which a dosage dependent zone of inhibition results was observed. Additionally, the catalytic potential of ZVSNPs was examined for the degradation of methylene blue dye in which an accelerated degradation of the dye was observed.Inspec keywords: antibacterial activity, crystallites, electrokinetic effects, scanning electron microscopy, nanoparticles, particle size, ultraviolet spectra, X‐ray chemical analysis, microorganisms, light scattering, nanofabrication, materials preparation, X‐ray diffraction, visible spectra, silver, dyes, Fourier transform infrared spectraOther keywords: wavelength 420.0 nm, Ag, voltage ‐15.7 mV, size 59.66 nm, size 0.39 nm, size 48.61 nm, electron volt energy 3.0 keV, Fourier transform infrared spectra, methylene blue dye, bactericidal action, dynamic light scattering, lattice parameter, Escherichia coli, Salmonella typhimurium, Spondias dulcis, negative zeta potential, polydispersity index, crystallite size, leaf extract, X‐ray diffraction, energy dispersive X‐ray spectrum, cuboidal‐shaped particles, scanning electron microscopy image, ultraviolet–visible spectrum, silver nitrate, zero‐valent silver nanoparticles     

Green synthesis of gold nanoparticles using Citrus maxima peel extract and their catalytic/antibacterial activities

The peel of Citrus maxima (C. maxima) is the primary byproducts during the process of fruit or juice in food industries, and it was always considered as biomass waste for further treatments. In this study, the authors reported a simple and eco‐friendly method to synthesise gold nanoparticles (AuNPs) using C. maxima peel extract as reducing and capping agents. The synthesised AuNPs were characterised by UV–visible spectrum, X‐ray diffraction (XRD), transmission electron microscope (TEM) and Fourier‐transform infrared spectroscopy (FTIR). The UV–visible spectrum of the AuNPs colloid showed a characteristic peak at 540 nm. The peaks of XRD analysis at (2θ) 38.30°, 44.28°, 64.62°, 77.57° and 81.75° were assigned to (111), (200), (220), (311) and (222) planes of the face‐centered cubic (fcc) lattice of gold. The TEM images showed that AuNPs were nearly spherical in shape with the size of 8–25 nm. The FTIR spectrum revealed that some bioactive compounds capped the surface of synthesised AuNPs. The biosynthesised AuNPs performed strong catalytic activity in degradation of 4‐nitrophenol to 4‐aminophenol and good antibacterial activity against both gram negative (Escherichia coli) and gram positive (Staphylococcus aureus) bacterium. The synthesis procedure was proved simple, cost effective and environment friendly.Inspec keywords: gold, nanoparticles, nanofabrication, X‐ray diffraction, ultraviolet spectra, visible spectra, transmission electron microscopy, Fourier transform infrared spectra, crystal structure, catalysis, antibacterial activity, nanobiotechnologyOther keywords: gold nanoparticles, Citrus maxima peel extract, UV–visible spectrum, X‐ray diffraction, transmission electron microscope, Fourier‐transform infrared spectroscopy, XRD analysis, faced centre cubic lattice, TEM images, catalytic activity, 4‐nitrophenol, 4‐aminophenol, antibacterial activity, gram negative bacterium, gram positive bacterium, Au     

Facile one‐pot hydrothermal synthesis of stable and biocompatible fluorescent carbon dots from lemon grass herb

Luminescent carbon‐based nanomaterials hold great promise due to their stable photo‐physical behaviour, biocompatibility and lower toxicity. This work involves economic and facile one‐pot green synthesis of water‐soluble nanostructures from lemon grass (LGNS) [Cymbopogon citratus (DC) Stapf] as carbon source. High‐resolution transmission electron microscopy confirmed the formation of LGNS with lattice spacing of 0.23 nm matching low‐dimensional graphitic structures. The strong absorption exhibited at 278 nm could be attributed to л‐states of sp² /sp³ hybridisation in carbon nanostructures. Fluorescence spectroscopy of LGNS exhibited strong excitation‐dependent emission properties over a broad range of wavelengths from 300 to 600 nm. Quantitatively, these LGNS were estimated to have quantum yield of 23.3%. Biomass derived LGNS could be potentially exploited for wide variety of applications like bioimaging, up‐conversion, drug delivery and optoelectronic devices. To this extent, synthesised LGNS were used to image yeast cells via multicolour/multi‐excitation fluorescence imaging.Inspec keywords: fluorescence, carbon, nanofabrication, photoluminescence, toxicology, transmission electron microscopy, cellular biophysics, biomedical optical imaging, nanomedicine, biomedical materials, microorganisms, liquid phase depositionOther keywords: one‐pot hydrothermal synthesis, biocompatible fluorescent carbon dots, lemon grass herb, luminescent carbon‐based nanomaterials, stable photophysical behaviour, toxicity, water‐soluble nanostructures, carbon source, high‐resolution transmission electron microscopy, low‐dimensional graphitic structures, hybridisation, carbon nanostructures, fluorescence spectroscopy, excitation‐dependent emission properties, biomass derived LGNS, bioimaging, drug delivery, optoelectronic devices, yeast cell image, multicolour‐multiexcitation fluorescence imaging, C     

Synthesis and comparative assessment of antiradical activity,toxicity, and biodistribution of κ‐carrageenan‐capped selenium nanoparticles of different size: in vivo and in vitro study

In the present study, water‐soluble hybrid selenium‐containing nanocomposites have been synthesised via soft oxidation of selenide‐anions, preliminarily generated from elemental bulk‐selenium in the base‐reduction system ‘N₂ H₄ –NaOH’. The nanocomposites obtained consist of Se⁰ NPs (4.6–24.5 nm) stabilised by κ‐carrageenan biocompatible polysaccharide. The structure of these composite nanomaterials has been proven using complementary physical–chemical methods: X‐ray diffraction analysis, transmission electron microscopy, optical spectroscopy, and dynamic light scattering. Optical ranges of ‘emission/excitation’ of aqueous solutions of nanocomposites with Se⁰ NPs of different sizes are established and the most important parameters of their luminescence are determined. For the obtained nanocomposites, the expressed antiradical activity against free radicals 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid has been found, the value of which depends on the size of selenium nanoparticles. It is experimentally revealed that all obtained nanocomposites are low toxic (LD₅₀ >2000 mg/kg). It is also found that small selenium nanoparticles (6.8 nm), in contrast to larger nanoparticles (24.5 nm), are accumulated in organisms to significantly increase the level of selenium in the liver, kidneys, and brain (in lesser amounts) of rats.Inspec keywords: nanobiotechnology, free radical reactions, oxidation, enzymes, selenium, solubility, nanofabrication, transmission electron microscopy, X‐ray diffraction, free radicals, reduction (chemical), biomedical materials, nanoparticles, nanomedicine, light scattering, organic‐inorganic hybrid materials, biochemistry, nanocompositesOther keywords: κ‐carrageenan biocompatible polysaccharide, composite nanomaterials, complementary physical–chemical methods, X‐ray diffraction analysis, transmission electron microscopy, optical spectroscopy, dynamic light scattering, optical ranges, expressed antiradical activity, 2,2‐diphenyl‐1‐picrylhydrazyl, 3‐ethylbenzothiazoline‐6‐sulphonic acid, comparative assessment, toxicity, κ‐carrageenan‐capped selenium nanoparticles, water‐soluble hybrid selenium‐containing nanocomposites, soft oxidation, selenide‐anions, elemental bulk‐selenium, base‐reduction system, free radicals, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid, selenium nanoparticles, nanocomposites, liver, kidneys, brain, luminescence, size 4.6 nm to 24.5 nm     

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     

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     

Larvicidal activity of green synthesized silver nanoparticles using Excoecaria agallocha L. (Euphorbiaceae) leaf extract against Aedes aegypti

Green synthesis of silver nanoparticles (AgNPs) using plant extracts has been achieved by eco‐friendly reducing and capping agents. The present study was conducted to evaluate the larvicidal efficacies of AgNPs synthesized using aqueous leaf extracts of Excoecaria agallocha against dengue vector, Aedes aegypti. The 3^rd and 4^th instar larvae of A. aegypti were exposed to various concentrations of aqueous extracts of E. agallocha, synthesized AgNPs and also crude solvent extracts (methanol and chloroform) for 24 h. The formation of AgNPs using aqueous leaf extracts was observed after 30 min with a characteristic colour change. The results recorded from UV‐Vis spectrum, XRD, FTIR, EDX, SEM and HR‐TEM were used to characterize and confirm the biosynthesis of AgNPs. The highest larvicidal efficacy of synthesized AgNPs was observed against 3^rd instar larvae at LC₅₀ 4.65 mg/L, LC₉₀ 14.17 mg/L and 4^th instar larvae with a concentration of LC₅₀ 6.10 mg/L, LC₉₀ 15.64 mg/L. A significant larvicidal activity was also observed with crude methanolic extracts against 3^rd instar larvae at a concentration LC₅₀ 41.74 mg/L, LC₉₀ 123.61 mg/L and 4^th instar larvae at a concentration of LC₅₀ 52.06 mg/L, LC₉₀ 166.40 mg/L as compared to the chloroform extract.Inspec keywords: silver, nanoparticles, nanofabrication, microorganisms, cellular biophysics, organic compounds, ultraviolet spectra, visible spectra, X‐ray diffraction, Fourier transform infrared spectra, X‐ray chemical analysis, scanning electron microscopy, transmission electron microscopyOther keywords: larvicidal activity, green synthesised silver nanoparticles, Excoecaria agallocha L. leaf extract, Aedes aegypti, plant extracts, capping agents, larvicidal efficacies, aqueous leaf extracts, excoecaria agallocha, dengue vector, Aedes aegypti, aegypti, aqueous extraction, E. agallocha, crude solvent extracts, methanol, chloroform, characteristic colour change, ultraviolet‐visible spectrum, X‐ray diffraction, Fourier‐transform infrared spectroscopy, EDX, scanning electron microscopy, high‐resolution transmission electron microscopy, AgNP biosynthesis, larvicidal efficacy, third instar larvae, instar larvae, crude methanolic extracts, chloroform extraction, time 24 h     

Design of 3‐aminophenol‐grafted polymer‐modified zinc sulphide nanoparticles as drug delivery system

Zinc sulphide (ZnS) nanoparticles were synthesized by the coprecipitation method. The ZnS nanoparticle surface was polymerized with allyl glycidyl ether (AGE), and 3‐aminophenol was then deposited as a ligand on nanosorbent. The modified nanosorbent was investigated with Fourier transform infrared spectroscopy and thermogravimetric analysis. The particle size of the modified nanosorbent was studied with scanning electron microscopy. Some characteristic factors of the adsorption process such as pH and time were investigated for famotidine using the modified nanosorbent. The equilibrium adsorption study of famotidine by 3‐aminophenol‐grafted AGE/ZnS was analysed by adsorption isotherms of the Langmuir, Freundlich, and Temkin models. The famotidine‐releasing process was investigated in simulated biological fluids (intestinal fluid at pH of 7.4 and gastric fluid at pH of 1.2) and demonstrated 65% and 73% famotidine release during periods of 30 h (pH = 7.4) and 60 min (pH = 1.2), respectively. These results reveal the optimal performance of 3‐aminophenol‐grafted AGE/ZnS for sustained drug delivery.     

Synthetically modified nano‐cellulose for the removal of chromium: a green nanotech perspective

Existing processes for the decontamination of heavy metals from water are found to be cost‐prohibitive and energy‐intensive which is totally against the sustainable concept of development. Green nanotechnology for water purification for ecosystem management, agricultural and industry is an emerging as leading global priority and occupies better position over the current state of water purification. Herein, the diafunctionalised polyaniline modified nanocellulose composite sorbent (PANI‐NCC) has been used to introduce amine and imine functionalities for the removal of trivalent and hexavalent chromium from water bodies. The fabricated nanobiomaterial has been authenticated by modern spectroscopic, microscopic techniques. The modified PANI‐NCC is rod‐like in shape, ~60 nm in size. The roughness and crystallinity index is also quantified and found to be 49.67 nm and 84.18%, respectively. The optimised experimental finding provides the efficient removal of trivalent [Cr(III)] (47.06 mg/g; 94.12%) and hexavalent [Cr(VI)] (48.92 mg/g; 97.84%) chromium from synthetic waste water. The fabricated nano biosorbent is deemed to be a potent biosorbent for technological development to remove the toxic metals in the real environmental water samples.Inspec keywords: decontamination, water pollution, purificationOther keywords: nano‐cellulose, decontamination, heavy metals, green nanotechnology, water purification, ecosystem management, agricultural, global priority, diafunctionalised polyaniline modified nanocellulose composite sorbent, PANI‐NCC, amine functionalities, imine functionalities, trivalent chromium, hexavalent chromium, water bodies, nanobiomaterial, crystallinity index, synthetic waste water, fabricated nano biosorbent, potent biosorbent, toxic metals, real environmental water samples     

Development and immunobiological evaluation of nanoparticles containing an immunodominant epitope of herpes simplex virus

Herpes simplex virus (HSV) 1 and 2 are viruses that infect individuals worldwide and for which there is no cure or vaccine available. The protective response against herpes is mostly mediated by CD8 T lymphocytes that respond to the immunodominant SSIEFARL epitope. However, there are some obstacles concerning the use of free SSIEFARL for vaccine or immunotherapy. The aim of this study was to evaluate the feasibility of nanoencapsulation of SSIEFARL and its immunostimulatory properties. Nano/SSIEFARL was produced by interfacial polymerization in methylmetacrylate, and the physico‐chemical properties, morphology and immunobiological parameters were evaluated. To evaluate the ex vivo capacity of Nano/SSIEFARL, we used splenocytes from HSV‐1‐infected mice to enhance the frequency of SSIEFARL‐specific CD8 T lymphocytes. The results indicate that Nano/SSIEFARL has a spherical shape, an average diameter of 352 ± 22 nm, the PDI was 0.361 ± 0.009 and is negatively charged (−26.30 ± 35). The stability at 4°C was 28 days. Also, Nano/SSIEFARL is not toxic for cells at low concentrations in vitro and it is taken up by JAWS II dendritic cells. No histopathological changes were observed in kidneys, liver and lymph nodes of animals treated with Nano/SSIEFARL. Nan/SSIEFARL increased the production of IL‐1β, TNF‐α and IL‐12 by the dendritic cells. Finally, Nano/SSIEFARL expanded the frequency of SSIEFARL‐specific CD8+T lymphocytes at the same rate as free SSIEFARL. In conclusion all data together indicate that SSIEFARL is suitable for nanoencapsulation, and the system produced presents some immunoadjuvant properties that can be used to improve the immune response against herpes.     

Efavirenz oral delivery via lipid nanocapsules: formulation,optimisation, and ex‐vivo gut permeation study

Present investigation aimed to prepare, optimise, and characterise lipid nanocapsules (LNCs) for improving the solubility and bioavailability of efavirenz (EFV). EFV‐loaded LNCs were prepared by the phase‐inversion temperature method and the influence of various formulation variables was assessed using Box–Behnken design. The prepared formulations were characterised for particle size, polydispersity index (PdI), zeta potential, encapsulation efficiency (EE), and release efficiency (RE). The biocompatibility of optimised formulation on Caco‐2 cells was determined using 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide assay. Then, it was subjected to ex‐vivo permeation using rat intestine. EFV‐loaded LNCs were found to be spherical shape in the range of 20–100 nm with EE of 82–97%. The best results obtained from LNCs prepared by 17.5% labrafac and 10% solutol HS15 when the volume ratio of the diluting aqueous phase to the initial emulsion was 3.5. The mean particle size, zeta potential, PdI, EE, drug loading%, and RE during 144 h of optimised formulation were confirmed to 60.71 nm, −35.93 mV, 0.09, 92.60, 7.39 and 55.96%, respectively. Optimised LNCs increased the ex vivo intestinal permeation of EFV when compared with drug suspension. Thus, LNCs could be promising for improved oral delivery of EFV.Inspec keywords: biomedical materials, solubility, drugs, encapsulation, emulsions, nanoparticles, particle size, nanofabrication, suspensions, toxicology, nanomedicine, cellular biophysics, lipid bilayers, electrokinetic effects, drug delivery systems, molecular biophysicsOther keywords: ex‐vivo permeation, diluting aqueous phase, mean particle size, zeta potential, drug loading, optimised formulation, ex vivo intestinal permeation, improved oral delivery, efavirenz oral delivery, optimisation, ex‐vivo gut permeation study, solubility, bioavailability, phase‐inversion temperature method, formulation variables, Box–Behnken design, polydispersity index, encapsulation efficiency, Caco‐2 cells, lipid nanocapsules, 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide assay, EFV‐loaded LNC, drug suspension, size 20.0 nm to 100.0 nm, time 144.0 hour, size 60.71 nm, voltage ‐35.93 mV     

Effects of nanosilver on sound absorption coefficients in solid wood species

Sound absorption coefficients (ACs) were determined in five solid woods (poplar, beech, walnut, mulberry, and fir) in the longitudinal and tangential directions at four different frequencies of 800, 1000, 2000, and 4000 Hz. The length of the longitudinal and tangential specimens was 50‐mm and 10‐mm, respectively. Separate sets of specimens were impregnated with either nanosilver suspension or water. The size range of nanoparticles was 30–80 nm. Results showed that sound ACs were lower in longitudinal specimens because sound waves could penetrate the open ends of vessels more easily, being trapped and damped there. Impregnation with both nanosilver suspension and water resulted in a significant decrease in the sound ACs. The decrease in the ACs was due to the collapsing and accumulation of perforation plates and cell parts, blocking the way through which waves could pass through the vessels. This caused higher damping due to a phenomenon called vibration decay. Correlation between gas permeability versus sound AC is significantly dependant on the porous structure of individual specimens.Inspec keywords: nanoparticles, silver, acoustic wave absorption, botany, wood, bioacoustics, suspensions, vibrations, nanobiotechnologyOther keywords: nanosilver effects, sound absorption coefficients, solid wood species, poplar, beech, walnut, mulberry, fir, nanosilver suspension, water, sound waves, impregnation, perforation plate collapsing, perforation plate accumulation, damping, vibration decay, gas permeability, sound AC, porous structure, size 30 nm to 80 nm, frequency 800 Hz, frequency 1000 Hz, frequency 2000 Hz, frequency 4000 Hz     

Effects of heat treatment on sound absorption coefficients in nanosilver‐impregnated and normal solid woods

Effects of impregnation with silver nano‐suspension as well as heat‐treatment on sound absorption coefficients (AC) were studied in tangential direction of five different solid woods based on their importance. AC was measured at two frequencies of 250 and 500 Hz. A 400 ppm nanosuspension was used for the impregnation; silver nanoparticles had a size range of 30–80 nm. Based on the obtained results, the species reacted significantly different in absorbing sound at the two frequencies. Impregnation with nano‐suspension substantially decreased AC at the lower frequency of 250 Hz; it did not show any particular trend when AC was measured at the frequency of 500 Hz. Heat treatment significantly increased AC at the frequency of 250 Hz. ACs of mulberry tended to be similar at the two frequencies; in the other four species though, ACs were significantly different. High significant correlations were found in the hardwoods between the ACs measured at the two frequencies.Inspec keywords: heat treatment, absorption coefficients, acoustic wave absorption, suspensions, silverOther keywords: Ag, frequency 500 Hz, frequency 250 Hz, mulberry, sound AC measurement, hardwoods, silver nanoparticles, silver nanosuspension, normal solid woods, nanosilver‐impregnated woods, sound absorption coefficients, heat treatment     

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 amides) on the surface of AgNPs. TEM studies indicate that synthesised AgNPs have average size of ∼2 nm. Energy dispersive X‐ray spectroscopy showed strong signal of Ag at 3 keV. Treatment of 1 mM AgNPs to the bajara seeds was found to be sufficient for excellent germination of seeds within 3 days. There was also significant increase in radicle and plumule length as compared with control bajara seeds according to statistical analysis by one‐way analysis of variance, followed by Tukey''s test. The percentage of AgNPs detected in root samples was 0.003% (by inductively coupled plasma atomic emission spectroscopy), which is negligible. There is still need to study the bioavailability and the type of interaction of AgNPs with plants, necessary for application in agriculture.Inspec keywords: transmission electron microscopy, ultraviolet spectra, scanning electron microscopy, nanofabrication, X‐ray diffraction, nanoparticles, visible spectra, silver, atomic emission spectroscopy, X‐ray chemical analysis, Fourier transform infrared spectra, statistical analysis, agricultureOther keywords: ultraviolet–visible absorption spectroscopy, transmission electron microscopy, Pennisetum glaucum, Bacillus subtilis spizizenni, energy dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy, optical absorption spectrum, plumule length, radicle length, silver nanoparticles, Tukey''s test, inductively coupled plasma atomic emission spectroscopy, statistical analysis, Bajara seeds, scanning electron microscopy, X‐ray diffraction, analysis of variance, electron volt energy 3.0 keV, time 3.0 d, Ag     

Synthesis of biopolymeric particles loaded with phosphorus and potassium: characterisation and release tests

The authors synthesised nanoparticles (NPs) loaded with P and K from KH₂ PO₄ using gelatin type‐A and type‐B, and sodium alginate as carriers. Using type‐A and type‐B gelatin, quasi‐spherical particles were obtained, with average sizes of 682 and 856 nm, respectively; with sodium alginate, the resulting NPs exhibited spherical shapes and 600 nm particle average size. The authors found an interaction between KH₂ PO₄ and alginate via the hydrogen bonds existent among the carboxylic groups of the carbohydrate and the OH‐groups of the H₂ PO₄ ‐; interactions among gelatin types with the OH‐groups and the H₂ PO₄ ‐ion were also observed. Adding trypsin to the distilled water solutions of the NPs coated with type‐A gelatin increased the concentration of P in the solution by threefold, while increasing that of K increased by 2.6‐fold. Conversely, adding α ‐amylase to the water solutions with sodium alginate increased the P and K concentrations in the solution by nearly 1.3‐ and 1.1‐fold, respectively. Thus, sodium alginate resulted in NPs with smaller sizes and better spherical formations, though with a high polydispersity index and lower release rate of P and K. This low release rate represents an advantage since plants demand nutrients for long periods, and conventional fertilisers display low use efficiency.Inspec keywords: nanofabrication, nanoparticles, hydrogen bonds, gelatin, biomedical materials, particle size, enzymes, molecular biophysics, biochemistry, nanobiotechnology, polymer films, potassium compoundsOther keywords: sodium alginate, biopolymeric particles, release tests, type‐B gelatin, spherical shapes, carboxylic groups, OH‐groups, distilled water solutions, type‐A gelatin, quasi‐spherical particles, particle average size, hydrogen bonds, trypsin, spherical formations, high polydispersity index, plants, α‐amylase, size 682.0 nm, size 856.0 nm, size 600.0 nm, H₂ PO₄ , KH₂ PO₄      

High thermal stability and low power dissipation PCM with nanoscale oxygen‐doped SS thin film

To improve thermal stability and reduce power dissipation of phase‐change memory (PCM), the oxygen‐doped Sn₁₅ Sb₈₅ (SS) thin film is proposed by magnetron sputtering in this study. Comparing to undoped Sn15Sb85(SS), the oxygen‐doped‐SS thin film has superior thermal stability and better data retention. Meanwhile, the electrical conductivity of crystallisation oxygen‐doped‐SS thin film is also lower than that of SS, which means its less power consuming in PCM. The electrical conductivity ratio between amorphous and crystalline states for oxygen‐doped SS reaches up to two orders of magnitude. After oxygen doping, the root‐mean‐square surface roughness from amorphous (0.29 nm) to crystalline (0.46 nm) state for oxygen‐doped‐SS thin films becomes smaller. The switching time of amorphisation process for the oxygen‐doped‐SS thin film (∼2.07 ns) is shorter than Ge₂ Sb₂ Te₅ (GST) (∼3.05 ns). X‐ray diffractometer is recorded to investigate the change of crystalline structure. Thus, the authors infer that oxygen‐doped SS is a promising phase‐change thin film for PCM.Inspec keywords: sputter deposition, antimony compounds, X‐ray diffraction, phase change memories, thin films, surface roughness, doping, electrical conductivity, amorphisation, crystallisation, thermal stability, amorphous state, crystal structure, nanostructured materials, nanofabrication, oxygenOther keywords: oxygen doping, low power dissipation, high thermal stability, phase‐change memory, magnetron sputtering, nanoscale oxygen‐doped Sn15Sb85 thin film, electrical conductivity, crystallisation, crystalline state, amorphous state, root‐mean‐square surface roughness, amorphisation process, X‐ray diffractometry, crystalline structure, Sn₁₅ Sb₈₅