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Background: 'Periodontitis' refers to periodontal destruction of connective tissue attachment and bone, in response to microorganisms forming subgingival biofilms on the root surface, while 'apical periodontitis' refers to periapical inflammatory processes occurring in response to microorganisms within the root canal system. The treatment of both diseases is based on the elimination of the bacterial challenge, though its predictability depends on the ability of disrupting these biofilms, what may need adjunctive antibacterial strategies, such as the next-generation antibacterial strategies (NGAS). From all the newly developed NGAS, the use of polymeric nanotechnology may pose a potential effective approach. Although some of these strategies have only been tested in vitro and in preclinical in vivo models, their use holds a great potential, and therefore, it is relevant to understand their mechanism of action and evaluate their scientific evidence of efficacy., Objectives: To explore NGAS based on polymeric nanotechnology used for the potential treatment of periodontitis and apical periodontitis., Method: A systemic search of scientific publications of adjunctive antimicrobial strategies using nanopolymers to treat periodontal and periapical diseases was conducted using The National Library of Medicine (MEDLINE by PubMed), The Cochrane Oral Health Group Trials Register, EMBASE and Web of Science., Results: Different polymeric nanoparticles, nanofibres and nanostructured hydrogels combined with antimicrobial substances have been identified in the periodontal literature, being the most commonly used nanopolymers of polycaprolactone, poly(lactic-co-glycolic acid) and chitosan. As antimicrobials, the most frequently used have been antibiotics, though other antimicrobial substances, such as metallic ions, peptides and naturally derived products, have also been added to the nanopolymers., Conclusion: Polymeric nanomaterials containing antimicrobial compounds may be considered as a potential NGAS. Its relative efficacy, however, is not well understood since most of the existing evidence is derived from in vitro or preclinical in vivo studies., (© 2024 The Authors. International Endodontic Journal published by John Wiley & Sons Ltd on behalf of British Endodontic Society.)

Wound healing is a complex process that orchestrates the coordinated action of various cells, cytokines and growth factors. Nanotechnology offers exciting new possibilities for enhancing the healing process by providing novel materials and approaches to deliver bioactive molecules to the wound site. This article elucidates recent advancements in utilizing nanoparticles, nanofibres and nanosheets for wound healing. It comprehensively discusses the advantages and limitations of each of these materials, as well as their potential applications in various types of wounds. Each of these materials, despite sharing common properties, can exhibit distinct practical characteristics that render them particularly valuable for healing various types of wounds. In this review, our primary focus is to provide a comprehensive overview of the current state-of-the-art in applying nanoparticles, nanofibres, nanosheets and their combinations to wound healing, serving as a valuable resource to guide researchers in their appropriate utilization of these nanomaterials in wound-healing research. Further studies are necessary to gain insight into the application of this type of nanomaterials in clinical settings., (© 2024 The Author(s). International Wound Journal published by Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

It is estimated that nearly a half of the world's population over 30 years old suffer from some kind of periodontal disease (PD). Although preventable, PD can pose a significant health burden to patients, causing from pain and discomfort to disfigurement and death. The management of PD often requires surgical procedures accompanied of systemic antibiotic and anti-inflammatory treatments. Curcumin (CUR), a potent anti-inflammatory and antimicrobial active, has shown great promise in the management of PD; however, its effects are often limited by its low bioavailability. In this work, we report the development of electrospun nanofibres (NFs) loaded with CUR nanocrystals (NCs) for the management of PD. NCs of 100 nm were obtained by media milling and loaded into dissolving polyvinyl alcohol NFs using electrospinning. The resultant NCs-in-NFs dissolved in water spontaneously, releasing NCs with a particle size of ∼120 nm. The physiochemical characterisation of the systems indicated the absence of chemical interactions between drug and polymer, and nanofibres with an amorphous nature. In vitro release profiles demonstrated that the NCs had a significantly higher dissolution rate (∼100 % at day 40) than the control group (approximately 6 % at day 40), which consisted of NFs containing a physical mixture of the drug and stabiliser. Finally, mucosal deposition studies demonstrated a 10-fold higher capacity of the novel NCs-in-NFs system to deposit CUR ex vivo using excised neonatal porcine mucosal tissue, when compared to the control group., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

We demonstrate a facile, one-step process to form polymer scaffolds composed of magnetic iron oxide nanoparticles (MNPs) contained within electrospun nano- and micro-fibres of two biocompatible polymers, Poly(ethylene oxide) (PEO) and Poly(vinyl pyrrolidone) (PVP). This was achieved with both needle and free-surface electrospinning systems demonstrating the scalability of the composite fibre manufacture; a 228 fold increase in fibre fabrication was observed for the free-surface system. In all cases the nanoparticle-nanofibre composite scaffolds displayed morphological properties as good as or better than those previously described and fabricated using complex multi-stage techniques. Fibres produced had an average diameter (Needle-spun: 125±18nm (PEO) and 1.58±0.28μm (PVP); Free-surface electrospun: 155±31nm (PEO)) similar to that reported previously, were smooth with no bead defects. Nanoparticle-nanofibre composites were characterised using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS) (Nanoparticle average diameter ranging from 8±3nm to 27±5nm), XRD (Phase of iron oxide nanoparticles identified as magnetite) and nuclear magnetic resonance relaxation measurements (NMR) (T1/T2: 32.44 for PEO fibres containing MNPs) were used to verify the magnetic behaviour of MNPs. This study represents a significant step forward for production rates of magnetic nanoparticle-nanofibre composite scaffolds by the electrospinning technique., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The paper reviews graphitic carbon nitride–based nanostructured photocatalytic materials and nanofibres for applications in water purification. Titanium dioxide has shown unique features that continue to attract research and development (R&D) due to its unique properties such as availability, ultraviolet absorptivity, photocatalysis, adsorption of pollutants and solar cell engineering. Graphitic carbon nitride is an attractive photocatalyst due to its non-toxicity characteristics, good visible light absorption and good thermal and chemical stabilities. In water purification, nanofibres are currently noticed due to their distinctive properties of effective separation and sometimes elimination of organic pollutants in water. In this review, synthesis and utility of doped titanium dioxide and carbon nitride with metal nanoparticles and polymeric nanofibres from nanocomposites as effective materials for the degradation of organic contaminations from water are discussed. The history, current trends and future perspectives are highlighted. [ABSTRACT FROM AUTHOR]

Nanobiotechnology provides novel set of tools to manipulate and enhance crop production using nanoparticles, nanofibres, nanoemulsions, and nanocapsules. Nanomaterials provide a platform to deliver agrochemicals and various macromolecules needed for plant growth enhancement and resistance to stresses. Smart delivery of agrochemicals increases the yield by optimizing water and nutrient conditions. Another added advantage is controlled release and site-directed delivery of agrochemicals. Further enhancement in quality and quantity in agriculture can be achieved by nanoparticle-mediated gene transformation and delivery of macromolecules that induces gene expression in plants. Various types of nanomaterials have been tested so far and the results have been promising in terms of productivity and quality enhancement.

Two kinds of Fe/C nanofibers were prepared by electrospinning and calcination under the same process conditions. A simple way was used to adjust the size of the Fe nanoparticles by using different spinning solvents. The one was prepared by a mixture of water and anhydrous alcohol as solvents (named as CNF water) and the other by N,N-Dimethylformamide and anhydrous alcohol (named as CNF DMF). Due to the higher solubility to iron salts and larger surface tension of water, CNF water gained a larger size of Fe nanoparticles and average diameter. In addition, the graphite layers wrapped on Fe nanoparticles which were formed during calcination were thinner in CNF water than CNF DMF. These factors endowed CNF water better microwave absorption performance. The results of XRD, SEM, HRTEM, Raman, magnetostatic and electromagnetic properties analysis revealed the influence mechanisms of solvents on the formation, microstructure and properties of Fe/C nanofibers. [ABSTRACT FROM AUTHOR]

In the modern pace of the world, food safety is a major concern. In this work, a simple chemiresistive type gas sensor was fabricated to detect Escherichia Coli (E. coli) bacteria. Polyaniline (PANI) films were deposited on the indium tin oxide substrate by an electrochemical deposition method. TiO2 nanoparticles were synthesised by facile hydrothermal method. PANI films were modified using hydrothermally prepared TiO2 nanoparticles by a spin coating method. X‐ray diffraction (XRD), field emission scanning electron microscope (FESEM), Fourier transform infrared (FTIR) and ultraviolet– visible spectrophotometer techniques were used to characterise the PANI/TiO2 nanocomposites. The peaks obtained in the XRD pattern confirmed the anatase phase of TiO2 nanoparticles. FESEM analysis showed the nanofibrous structure of the nanocomposite. The FTIR characteristic peaks confirmed the formation of the nanocomposite. The electrical resistance of the sensors was evaluated as a function of the bacterial concentration. The PT2 (TiO2 coated 5 times on PANI) in comparison with PT1 (TiO2 coated 3 times on PANI) exhibited good sensitivity to the gas molecules at room temperature. The p‐n junction at PANI/TiO2 interface improved the physical adsorption of gas molecules. Since no specific antibodies or receptors are used, the sensor has the potential for adaptation to real‐life applications. Thus low cost, real‐time, portable, reusable and sensitive bacteria sensors were fabricated and tested. [ABSTRACT FROM AUTHOR]

Armies of powerful armed forces are already applying achievements of nanoscience and supporting researches in the field of nanotechnology. This paper surveys the recent research in the area of nanomaterials application in defence technologies, conducted in the Military Technical Institute in Belgrade, Serbia. This research covers the most important results obtained so far in the following areas: chemical biological, radiological and nuclear protection (CBRN protection), nanomodified polymer coatings and camouflage paints, composite structures for military aircraft, ballistic protection composites, and energetic materials. Researches gave promising results in all the named fields and encourage nanomaterials application in future.

Carbon aerogels have attracted considerable attention in basic research and for their potential applications in many fields. Here, the fabrication of a magnetic cellulose nanofibre (CNF)/poly(vinyl alcohol) (PVA)/multiwalled carbon nanotubes (MWCNT) carbon aerogel (m‐CPMCA) is reported using a simple freeze‐drying followed by a carbonisation process, and direct immobilisation of Fe3 O4 nanoparticle on the surface of aerogels. The obtained target aerogel has the characteristics of low density (0.098 g/cm3), high porosity (>90%) and 3D interpenetrating porous structures. Furthermore, m‐CPMCA has a surprising compressive strength (about 0.35 MPa) which is obviously higher than many other cellulose‐based carbon aerogels. After Carbonization, m‐CPMCA exhibits superhydrophobicity, selective absorption for organic solvents and fire‐resistance. The m‐CPMCA also exhibited a magnetic response and can absorb oil on the water surface and can be actuated by a small magnet. More importantly, the m‐CPMCA could be recycled many times by combustion, which showed economic significance. To sum up, the authors believe that m‐CPMCA will become a very potential adsorbent for dealing with the increasingly serious problem of organic pollution. [ABSTRACT FROM AUTHOR]

The article presents an overview of electrospinning process development from the first investigations in the field of behaviour of liquids in an electrostatic field to the electrospinning methods and investigations in the 21st century. The article presents the history of electrospinning process development, the main problems that are solved, and also indicates the gaps in the field of standardisation of nanofibrous web structure measurement and estimation. There are a lot of works in which authors analyse influences of various parameters on the electrospinning process or on the structure of electrospun web, whereas the majority of them do not analyse the quality of structure using mathematical criteria. Such a situation leads to different conclusions and makes it impossible to compare various works by different authors. Despite numerous studies in electrospinning, investigations in the electrospun nanofibrous web estimation are not sufficient. Until now, a unique standard method for measuring and estimating the fibre diameter and web porosity has not been developed. The necessity of such a method and standards is obvious, and the lack of such a standard could have a negative influence on the electrospun product introduction into the market. [ABSTRACT FROM AUTHOR]

The authors report a facile approach to high‐purity carbon nanofibres (CNFs), by performing chemical vapour deposition on aluminium foils loaded with metal (nickel or cobalt) nitrates, and then peeling the as‐grown CNFs off. The growth of CNFs was catalysed by metal nanoparticles and followed bottom‐growth mechanism, and the high‐purity CNFs were achieved due to detachment of CNFs from their underlying metal nanoparticles during the peeling process. This approach may pave a new way for the controlled and scalable synthesis of high‐purity carbon materials. [ABSTRACT FROM AUTHOR]

Water is polluted by the effluents discharged from various industries and some of the pollutants are acids, dyes, heavy metals and nanoparticles. The polluted water bodies lead to the lack of safe drinking water. Hence an efficient method is required to remove the pollutants from the wastewater. Membrane technology is an emerging technology used for water treatment. Among the various membrane fabrication techniques, electrospinning gained popularity because of its large surface area to volume ratio and high porosity. Many polymeric nanofibre membranes have been prepared by using electrospinning technique. Electrospun nanofibre membranes have been extensively studied for the removal of hazardous pollutants from the wastewater. This review paper tells how the electrospinning works to produce nanofibres from polymeric solution, in what ways these polymeric electrospun nanofibre membranes are modified and by which mechanism the electrospun polymeric nanofibre membranes removes or degrades the pollutants from the water. [ABSTRACT FROM AUTHOR]

The isolated Gluconacetobacter sp. with accession number: KY996741 was assayed for evaluation of phytase activity. It could solubilise sodium phytate in the absence of soluble phosphate with the cells; however, the enzyme was not seen in cell free extract, to the best of their knowledge the intracellular phytase activities of Gluconacetobacter sp. was not reported previously. Also, the potential of in situ immobilisation of cells produced enzyme (/phytase producing bacteria) in bacterial cellulose was investigated and was studied by SEM and AFM. The results showed that the immobilised probiotic cells had the best activity of 1229 U/ml. The optimum temperature of the immobilised enzyme activity was at 45°C (5969 U/ml) and the immobilised phytase maintained 64% of its activities after two repeated cycles. The enzyme needs mild conditions for its activity and has a short life time and low stability and lost activities from 1229 to 500 U/ml during 30 days. However, it was showed that the addition of 1 ppm nano‐ferric oxide particles could promote the phytase activities of immobilised cell from 500 U/ml to >1500 U/ml. This immobilised phytase producing cells on bacterial cellulose can be useful as food and/feed supplement for phytin removal. [ABSTRACT FROM AUTHOR]

In this report, a novel wound dressing material has been woven by electrospinning technique and tested for its various properties. For the nanofibre mat, a mixture of polyurethane (PU) and soy protein isolate (SPI) was electrospun in conjugation with zinc oxide nanoparticles (ZnO Nps) and ciprofloxacin hydrochloride (CipHCl) to produce fibrous mats viz. PU/SPI/ZnO and PU/SPI/CipHCl. An optimum ratio (1 : 1) of PU/SPI was used as suitable polymeric ratio in order to produce homogenous nanofibres without beads having an average diameter in the range of 300–350 nm. The electrospun nanofibre‐based mats were characterised using X‐ray diffraction, Fourier transform infrared spectroscopy, ultraviolet‐visible spectroscopy, thermogravimetric analysis and scanning electron microscope. The mechanical properties of the nanofibrous mats were tested using universal testing machine. The wettability analysis was done using the contact angle measurement based on the sessile drop test. This study revealed that the electrospun PU/SPI‐based nanofibres are non‐sensitizing, non‐allergic and non‐toxic and that it can be used as a peculiar wound healing material. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPEs) have great potential to address the safety issues of lithium (Li)-ion batteries when compared with conventional liquid electrolytes, which makes them a promising alternative for next-generation high-energy batteries. In this work, poly(ethylene oxide)-lithium perchlorate (PEO–LiClO(4)) polymer electrolytes for Li-ion batteries were prepared using electrospinning. The crystallinity, ionic conductivity as well as mechanical properties were investigated. Ionic conductivities and mechanical properties of PEO–LiClO(4) based SPE have been obviously increased by incorporating modified TiO(2) nanofibres (TNFs) than TiO(2) nanoparticles (TNPs), due to that both TNFs and TNPs can decrease the crystalline phase concentration of PEO and increase segmental flexibility of PEO. The SPE with 3 wt% TNFs exhibits the highest conductivity of 5.308 × 10^−5 S cm^−1 at 20°C and higher tensile strength of 13.8 MPa. These results highlight the potential of utilising the electrospinning method to improve the ionic conductivity of SPEs.

Limonene, a natural solvent, has been used for producing polystyrene (PS) nanocomposite (NC) fibres. Nanocomposite fibres of PS are prepared by electrospinning of a homogeneous solution of titanium dioxide (TiO2) nanoparticles (NPs) and PS. X-ray diffraction (XRD) pattern of PS nanocomposite fibres confirms the presence of TiO2 nanoparticles in the samples. FTIR spectra of PS nanocomposite fibres obviously show that there is no chemical linkage or interaction between PS and TiO2 nanoparticles in the resulting composites fibres. The morphology of PS electrospun fibres and PS/TiO2 nanocomposite fibres is investigated by SEM and FE-SEM. FE-SEM images of electrospun fibres reveal some aggregation of TiO2 nanoparticles. The results also show that increasing TiO2 nanoparticles reduces PS electrospun fibres diameter. Also, the UV protection of PS electrospun fibres is enhanced due to the increase in TiO2 nanoparticles load. Tensile strength and elasticity modulus first show an increase up to 4 wt% of TiO2 and then a decrease at higher loading. Differential scanning calorimeter (DSC) thermograms for PS electrospun fibres indicate that the introduction of TiO2 nanoparticles decreases the glass transition temperature (Tg). [ABSTRACT FROM AUTHOR]

A novel and facile approach to prepare hybrid nanoparticle embedded polymer nanofibers using pressurised gyration is presented. Silver nanoparticles and nylon polymer were used in this work. The polymer solution's physical properties, rotating speed and the working pressure had a significant influence on the fibre diameter and the morphology. Fibres in the range of 60–500 nm were spun using 10 wt.%, 15 wt.% and 20 wt.% nylon solutions and these bead-free fibres were processed under 0.2 MPa and 0.3 MPa working pressure and a rotational speed of 36,000 rpm. 1–4 wt.% of Ag was added to these nylon solutions and in the case of wt.% fibres in the range 50–150 nm were prepared using the same conditions of pressurised gyration. Successful incorporation of the Ag nanoparticles in nylon nanofibres was confirmed by using a combination of advanced microscopical techniques and Raman spectrometry was used to study the bonding characteristics of nylon and the Ag nanoparticles. Inductively coupled plasma mass spectroscopy showed a substantial concentration of Ag ions in the nylon fibre matrix which is essential for producing effective antibacterial properties. Antibacterial activity of the Ag-loaded nanofibres shows higher efficacy than nylon nanofibres for Gram-negative Escherichia coli and Pseudomonas aeruginosa microorganisms, and both Ag nanoparticles and the Ag ions were found to be the reason for enhanced cell death in the bacterial solutions. [ABSTRACT FROM AUTHOR]

SiC nanoparticles and nanofibres were synthesised by simple carbothermal reduction technology. Low cost water glass and phenolic resin were used as raw materials, and nickel nitrate was added as catalyst. The synthesised samples were characterised by X-ray diffraction, field emission scanning electron microscope, TEM, N2 adsorption-desorption isotherms and fluorescence spectrophotometer. The results indicate that nickel catalyst can change the morphology and the surface area of SiC. When molar ratio of nickel to silicon equals to 0·0141, SiC nanoparticles with an average diameter of 40 nm are synthesised, and the surface area reaches maximum value, 81 m2 g−1. However, SiC nanofibres are prepared with the increase in nickel content, but the surface area decreases. The synthesised SiC have stable and strong photoluminescence property. The synthetic technique has the advantage of being simple, efficient and economical. [ABSTRACT FROM AUTHOR]

In this study, polyamide-6 (PA-6) nanofibre membranes containing TiO2 nanoparticles were successfully prepared by electrospinning. Different types of TiO2 functionalisation methods (inline functionalisation and post-functionalisation) were tested with two types of TiO2 nanoparticles. A colloidal solution consisting of TiO2 nanoparticles with average dimensions of 6 nm was prepared and the performance of these nanoparticles was compared with commercially available Degussa P25 nanoparticles. The photocatalytic activity of the nanofibre membranes functionalised with TiO2 was demonstrated with the degradation of the dye methylene blue. The results of photodegradation with methylene blue in aqueous solution demonstrated excellent photocatalytic activity of TiO2 nanoparticles immobilised in and on the nanofibrous structure. After 2 h of UV irradiation, a degradation up to 84% methylene blue was observed. This degradation further increased and resulted in a degradation up to 99% methylene blue after 6 h of illumination. A stability test of the functional materials confirmed that the TiO2 nanoparticles were successfully incorporated in and onto the electrospun PA-6 fibres. Clean water flux was measured to find out the filter efficiency of the different membranes. The functionalised membranes have a clean water-flux varying from 1.0 x 104 to 2.1 x 104 l/m² h bar. As such, the electrospun nanofibre membranes functionalised with TiO2 nanoparticles show a great potential as a water filter medium with an immobilised photocatalyst in view of dissolved organic matter degradation. [ABSTRACT FROM AUTHOR]

Natural‐synthetic blend nanofibres have recently attracted more interest because of the ability of achieving desirable properties. Poly(ε‐caprolactone) (PCL)‐chitosan (Cs)‐poly(vinyl alcohol) (PVA) blend nanofibrous scaffolds were electrospun in 2:1:1.33 mass ratio of PCL:Cs:PVA. The presence of PCL in the blend leads to improvement in web hydrophobicity and helped the web to retain its integrity in aqueous media. The scaffolds were used in two forms of acellular and with mesenchymal stem cells. They were applied on burn (n = 12) and excisional cutting (n = 12) wounds on dorsum skin of rats. Macroscopic investigations were carried out to measure the wounds areas. It was found that the area of wounds that were treated with cell‐seeded nanofibrous scaffolds were smaller compared to other samples. Pathological results showed much better healing performance for cell‐seeded scaffolds followed by acellular scaffolds compared with control samples. All these results indicate that PCL:Cs:PVA nanofibrous web would be a proper material for burn and cutting wound healing. [ABSTRACT FROM AUTHOR]

Abstract: The complementary capabilities of various characterisation methods for micro-structural assessment are demonstrated. The assessed structures were composed of unbleached microfibrillated cellulose (MFC) in combination with bleached and 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) pre-treated MFC materials. The biodegradable nano-composites were thus characterised in detail, including laser profilometry, scanning electron microscopy (SEM) in high and low vacuum modes, and field-emission SEM. The distribution of the unbleached MFC materials was assessed by staining the unbleached MFC with osmium tetroxide (OsO4), which reacts with Cbonds encountered in lignin. In addition, some properties of the MFC nano-composite films were tested, i.e. tensile properties, water wettability and oxygen permeability. In general, the group of characteristics of the nano-composite MFC films was better than the properties of the films made of the neat MFC qualities. This indicates that mixing complementary MFC qualities could give synergetic effects that are not exploited completely when using the MFC qualities separately. The study thus confirms the suitability of unbleached MFC materials as a component in multilayer structures, for example biodegradable packaging applications. [Copyright &y& Elsevier]

Abstract: The novel poly(lactic acid) (PLA)/TiO2 hybrid nanofibres are produced via electrospinning technique. Hydrolysed titanium precursor has been electrosprayed simultaneously on the continuous electrospun PLA nanofibres surface. The adhered amorphous titania has been transformed into TiO2 particle through hydrothermal treatment for different times. The phase structure has been worked out using XRD, FTIR, XPS and Raman spectroscopy. The predominant phase is anatase with a small extent of brookite phase after the hydrothermal treatment. The size and location of TiO2 particle have been determined using SEM micrographs. The orderness of the PLA crystallites has been checked using XRD patterns before and after hydrothermal treatment. UV absorption capability of the titania coated nanofibres has been enhanced to a significant level. The antimicrobial activity of the hybrids has been verified using two different microorganisms (gram negative Escherichia coli and gram positive Staphylococcus aureus bacteria) and 70% reduction of antimicrobial activity has been reported. [Copyright &y& Elsevier]

A brief introduction to the development of electrospinning is given, and various apparatus to fabricate nanofibres or nanoporous materials are systematically reviewed with emphasis on the vibration electrospinning and melt electrospinning for enlarging electrospinability, siro-electrospinning for mimicking the spinning procedure of a spider, magneto-electrospinning for controlling the instability arising in the electrospinning process and bubble electrospinning for mass production of nanofibres. Electrospinning for producing nanoporous materials and the nano-effect for improving the properties of nanofibres are also introduced. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a newly designed biohydrogen fuel cell by integrating a bioreactor for hydrogen production with the anode chamber in a hydrogen fuel cell. Two different composites of platinum nanoparticles decorated on functionalised multi-walled carbon nanotubes (Pt/fMWCNTs) and polyaniline (PANI) were fabricated using the electrochemical polymerisation method and used as anodes. The biohydrogen fuel cell using a thin film of PANI nanofibres deposited on Pt/fMWCNTs/carbon paper as the anode showed much higher power density than the cell using a core–shell structure PANI/Pt/fMWCNTs and Pt/fMWCNTs without PANI based anodes. The structural differences between these two composites and their effects on the interaction with hydrogen gas inside the anode chamber leading to the difference in power density of the fuel cell were also discussed. The maximum power density was 613.5mWm−2, which was obtained at a current density of about 2.55Am−2 with a cell voltage of 0.24V using 20mL single-chamber air-cathode, compact biohydrogen fuel cell. [Copyright &y& Elsevier]

A new series of poly(vinyl pyrrolidone) (PVP) and silver chloride nanoparticles (AgCl) composite fibres have been synthesized by electrospinning and gel-sol technology. We used sol-gel process to prepare AgCl nanoparticles in the PVP solution, and then the solutions were electrospun to obtain AgCl/PVP composite nanofibres. The final products were thoroughly characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and field-emission scanning electron microscopy (FESEM), which showed the formation of AgCl nanoparticles/PVP composite nanofibres. [ABSTRACT FROM AUTHOR]

Nanoscience and nanotechnology are considered to be the key technologies for the current century. Efforts are being made worldwide to create smart and intelligent textiles by incorporating various nanoparticles or creating nanostructured surfaces and nanofibres which lead to unprecedented level of textile performance, such as stain resistant, self-cleaning, antistatic, UV protective, etc. However, there are many challenges in the research and development of nanotechnology based products. The precise control of nanoparticle size, size distribution, dispersion at nanolevel and deposition on textile substrate needs sophisticated characterization techniques, such as particle size analyzer, electron microscopy (SEM/TEM/HRTEM), atomic force microscopy, X-ray diffraction, Raman spectroscopy, X-ray photon spectroscopy, etc. This paper discusses the basic principle and applications of these instrumental techniques in the field of nanotechnology research in textiles. [ABSTRACT FROM AUTHOR]

Abstract: Nanofibres of poly(amideimide) (PAI) were prepared by electrospinning from solutions of 11wt% PAI in dimethylformamide. Addition of small amounts of citric acid to the spinning solution improved the fibre size and fibre uniformity. Catalytic activation of the electrospun nanofibres was performed by coating the fibres with an organic solution of palladium diacetate containing citric acid onto the fibres and subsequent thermally induced conversion to nanosized palladium clusters. The catalyst was durably fixed on the fibres by this procedure. The presence of palladium (Pd) nanoparticles was confirmed by R-ray-diffractometry. These fibres were applied in the hydrogenation of methyl-cis-9-octadecenoate as a model reaction. The palladium-doped nanofibres showed an almost seven times higher hydrogenation rate than a commercial palladium catalyst supported on alumina. [Copyright &y& Elsevier]

Defence personnel face multiple threats from different quarters, like terrorist groups and rogue nations, who own not only advanced lethal weapons but also chemical and biological warfare weapons. The present day protective clothing system used by the defence sector is vulnerable to modern weapons and also have some inherent weaknesses like high cost, bulkiness and discomfort in wearing. Nanotechnology- based materials offer a promising future in this area due to their extraordinary physical, chemical, mechanical, and electrical properties at nano-level. This paper outlines the various developments related to the application of nanotechnology in producing lightweight and comfortable protective clothing for the military personnel and also some new developments like sensor, energy storage, conductivity, and decontaminant fabrics. [ABSTRACT FROM AUTHOR]

Abstract: Laser Spinning is a new technique for the production of glass fibres with diameters in the nanometre to micrometre scale. It allows large quantities of nanofibres to be made with specific, controllable chemical compositions. Furthermore, the production of amorphous micro- and nanofibres of non-ready glass former materials was demonstrated. All these novel characteristics will potentially open up a whole new range of applications for the fibres. In this technique a high power laser is employed to melt the precursor solid material, while a supersonic gas jet is injected into the melt volume. The melt forms glass fibres as a result of its viscous elongation and cooling by the drag force and convective heat transfer produced by the gas jet. The influence of several operating conditions controlling the morphology, composition, and diameter distribution of the fibres is experimentally assessed by means of electron microscopy analysis, X-ray fluorescence and time-of-flight secondary ion mass spectrometry. The experimental results are discussed based on a theoretical explanation of the process of fibre formation. This leads ultimately to the deduction of a set of rules regarding the influence of the factors studied on the production of nanofibres by Laser Spinning. [Copyright &y& Elsevier]