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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The outbreak of COVID‐19 disease, the cause of severe acute respiratory syndrome, is considered a worldwide public health concern. Although studies indicated that the virus could spread through respiratory particles or droplets in close contact, current research have revealed that the virus stays viable in aerosols for several hours. Numerous investigations have highlighted the protective role of air purifiers in the management of COVID‐19 transmission, however, there are still some doubts regarding the efficiency and safety of these technologies. According to those observations, using a proper ventilation system can extensively decrease the spread of COVID‐19. However, most of those strategies are currently in the experimental stages. This review aimed at summarising the safety and effectiveness of the recent approaches in this field including using nanofibres that prevent the spread of airborne viruses like SARS‐CoV‐2. Here, the efficacy of controlling COVID‐19 by means of combining multiple strategies is comprehensively discussed. [ABSTRACT FROM AUTHOR]

Aim: Guided tissue regeneration has been considered a promising strategy to replace conventional endodontic therapy of teeth with incomplete root formation. Therefore, the objective of this study was to develop a tubular scaffold (TB‐SC) with poly (caprolactone)‐aligned nanofibres associated with a fibronectin (FN)‐loaded collagen hydrogel and assess the pulp regeneration potential mediated by human apical papilla cells (hAPCs) using an in vitro model of teeth with incomplete root formation. Methodology: Aligned nanofibre strips based on 10% poly(caprolactone) (PCL) were synthesized with the electrospinning technique to produce the TB‐SCs. These were submitted to different treatments, according to the following groups: TB‐SC (negative control): TB‐SC without treatment; TB‐SC + FN (positive control): TB‐SC coated with 10 μg/ml of FN; TB‐SC + H: TB‐SC associated with collagen hydrogel; TB‐SC + HFN: TB‐SC associated with FN‐loaded collagen hydrogel. Then, the biomaterials were inserted into cylindrical devices to mimic the regenerative therapy of teeth with incomplete root formation. The hAPCs were seeded on the upper surface of the TB‐SCs associated or not with any treatment, and cell migration/proliferation and the gene expression of markers related to pulp regeneration (ITGA5, ITGAV, COL1A1 and COL1A3) were evaluated. The data were submitted to anova/Tukey's tests (α = 5%). Results: Higher values of cell migration/proliferation and gene expression of all markers tested were observed in groups TB‐SC + FN, TB‐SC + H, and TB‐SC + HFN compared with the TB‐SC group (p <.05). The hAPCs in the TB‐SC + HFN group showed the highest values of cell proliferation and gene expression of COL1A1 and COL3A1 (p <.05), as well as superior cell migration results to groups TB‐SC and TB‐SC + H (p <.05). Conclusion: Aligned nanofibre scaffolds associated with the FN‐loaded collagen hydrogel enhanced the migration and proliferation of hAPCs and gene expression of pulp regeneration markers. Therefore, the use of these biomaterials may be considered an interesting strategy for regenerative pulp therapy of teeth with incomplete root formation. [ABSTRACT FROM AUTHOR]

There have been strong demands for nanofibrous scaffolds fabricated by electrospinning for various fields due to their various advantages. Electrospun poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) fibre mats were prepared. The effects of processing variables as well as the inclusion of poly(ethylene glycol) (PEG) on the morphologies of generated fibres were investigated using Fourier‐transform infrared spectroscopy and scanning electron microscopy. The average fibrous diameter was monitored in the range 400–3000 nm relying on the total content of PEG. The fluorescence cell imaging of electrospun mats was also explored. The results of cell viability demonstrated that skin fibroblast BJ‐1 cells showed different adhesions and growth rates for the three kinds of PHBV fibres. Electrospun PHBV mats with low amount of PEG offer a high‐quality medium for cell growth. Therefore, those mats exhibited high potential for soft tissue engineering, in particular wound healing. [ABSTRACT FROM AUTHOR]

Aims: We aim to evaluate if the myelin pathology observed in epilepsy‐associated focal cortical dysplasia type 2B (FCD2B) and—histologically indistinguishable—cortical tubers of tuberous sclerosis complex (TSC) is primarily related to the underlying malformation or constitutes a secondary phenomenon due to the toxic microenvironment created by epileptic seizures. We also aim to investigate the possible beneficial effect of the mTOR pathway regulator everolimus on white matter pathology. Methods: Primary mixed glial cell cultures derived from epilepsy surgery specimens of one TSC and seven FCD2B patients were grown on polycaprolactone fibre matrices and analysed using immunofluorescence and electron microscopy. Unaffected white matter from three age‐matched epilepsy patients with mild malformations of cortical development (mMCD) and one with FCD3D served as controls. Additionally, TSC2 knock‐out was performed using an oligodendroglial cell line. Myelination capacities of nanofibre grown cells in an inflammatory environment after mTOR‐inhibitor treatment with everolimus were further investigated. Results: Reduced oligodendroglial turnover, directly related to a lower myelin content was found in the patients' primary cells. In our culture model of myelination dynamics, primary cells grown under 'inflammatory condition' showed decreased myelination, that was repaired by treatment with everolimus. Conclusions: Results obtained in patient‐derived primary oligodendroglial and TSC2 knock‐out cells suggest that maturation of oligodendroglia and production of a proper myelin sheath seem to be impaired as a result of mTOR pathway disturbance. Hence, oligodendroglial pathology may reflect a more direct effect of the abnormal genetic programme rather than to be an inactive bystander of chronic epilepsy. [ABSTRACT FROM AUTHOR]

Bioactive nanofibres play a useful role in increasing the efficiency of tissue engineering scaffolds. MicroRNAs (miRs) alone, and in combination with tissue engineering scaffolds, can be effective in treating bone fractures and osteoporosis by regulating many post‐transcriptional cellular pathways. Herein, miR‐181a/b‐1 was incorporated in the electrospun poly (lactic‐co‐glycolic acid) (PLGA) nanofibres (PLGA‐miR). After characterization scaffolds, the osteoinductive capacity of the nanofibres was investigated when adipose‐derived mesenchymal stem cells (AT‐MSCs) were cultured on the PLGA and PLGA‐miR nanofibres. miR incorporating in the nanofibres has not any significant effect on the size and morphology of the nanofibres, but its biocompatibility was increased significantly compared to the empty nanofibres. Alkaline phosphatase (ALP) activity and calcium measures were evaluated as two important osteogenic markers, and the results revealed that the highest measures were observed in the AT‐MSCs cultured on PLGA‐miR nanofibres. Detected ALP activity and calcium measures in miR‐transduced AT‐MSCs cultured on TCPS were also significantly higher than AT‐MSCs cultured on PLGA and TCPS groups. The highest expression levels of bone‐related genes were observed in the AT‐MSCs cultured on PLGA‐miR nanofibres. This improvement in the osteogenic differentiation potential of the AT‐MSCs was also confirmed by evaluating osteopontin protein in the cells cultured on PLGA‐miR. It can be concluded that miR‐181a/b‐1 has a significant impact on the AT‐MSC osteogenic differentiation, and this impact synergistically increased when incorporated in the PLGA nanofibres. [ABSTRACT FROM AUTHOR]

Umbilical cord‐derived mesenchymal stem cells (UCDMSC) are attractive candidates for cell‐based regenerative medicine. However, they are susceptible to replicative senescence during repetitive passaging for in‐vitro expansion and induced senescence in an oxidative, inflammatory microenvironment in vivo. Aim of this study is to investigate if honey‐incorporated matrices can be employed to reduce senescence of UCDMSC. Matrices were prepared by electrospinning solutions of honey with poly‐vinyl alcohol (PVA). PVA:honey matrices exhibited free radical scavenging activity. Culture of UCDMSC on PVA:honey matrices showed improvement in cell proliferation compared to pure PVA nanofibres. Expression of vimentin indicated that mesenchymal phenotype is preserved after culturing on these matrices. Further, UCDMSC were serially subcultured and cells of two passages (P2 and P6) were evaluated for reactive oxygen species (ROS) load and senescence parameters. P6 cells showed a higher ROS load and β‐galactosidase (β‐gal) positive senescent cells compared to P2. However, culturing on PVA:honey substrates significantly reduced both ROS and β‐gal markers compared to cells on PVA substrates. Honey contains several antioxidant and anti‐inflammatory components, which can reduce the ROS‐related senescence. Thus, it is concluded that honey containing nanofibres can be effective substrates for stem cell‐based wound healing and regenerative medicine. [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]

In this study, probiotic yeast Saccharomycopsis fibuligera (S. fibuligera) VIT‐MN04 was encapsulated with wheat bran fibre (WBF) and exopolysaccharide (EPS) along with 5% polyvinylpyrrolidone (PVP) using electrospinning technique for easy gastrointestinal transit (GIT). The electrospinning materials viz. WBF (10%), EPS (15%), PVP (5%) and electrospinning parameters viz. applied voltage (10 kV) and tip to collector distance (15 cm) were optimised using response surface methodology to produce fine nanofibres to achieve maximum encapsulation efficiency (100%) and GIT tolerance (97%). The probiotic yeast was successfully encapsulated in nanofibre and investigated for potential properties. The survival of encapsulated S. fibuligera VIT‐MN04 was increased compared to the free cells during in vitro digestion. In addition, encapsulated yeast cells retained their viability during storage at 4°C for 56 days. The nanofibres were characterised using scanning electron microscopy, atomic force microscopy, X‐ray diffraction, thermogravimetric analysis, zeta potential analysis and Fourier transform infrared spectroscopy followed by gas chromatography–mass spectrometry and nuclear magnetic resonance analysis. This work provides an efficient approach for encapsulation of probiotic yeast with the nanofibres which can also broaden the application of the prebiotic like WBF providing an idea for the efficient preparation of functional synbiotic supplements in the food industry. [ABSTRACT FROM AUTHOR]

Chitosan nanofibre–apatite nuclei composites obtained by mixing apatite nuclei which possess high apatite‐forming ability with chitosan nanofibre have been expected to be novel bone restorative materials with suitable properties such as light weight, low coefficient of thermal expansion, high mechanical strength, biocompatibility and bioactivity. In this study, the authors prepared three types of apatite nuclei by changing the reaction time aimed to optimise their crystallinity and fabricated their composites with chitosan nanofibre. In order to evaluate the bioactivity in vitro, the authors tested apatite‐forming ability in simulated body fluid. As a result, the materials showed enough apatite‐forming ability in a short time by mixing chitosan nanofibre and apatite nuclei with extremely low crystallinity and their high reactivity in simulated body fluid. [ABSTRACT FROM AUTHOR]

In the present study, the novel keratin-based 5-fluorouracil (5-FU) releasing nanofibrous system was electrospun. The pH sensitivity releasing performances of the nanofibres were optimised by a full-factorial matrix design of experiment (DoE) with two significant factors at two levels in different pH environments. This full-factorial DoE methods was applied to identify the main effects of these composite bio-functional nanofibres and investigate the interaction effects of multiple factors. The SEM images indicated that a more homogeneous microstructure of the composite nanofibres was observed at the low level of electrospun voltage, which was set at 15 kV. The FTIR test detected the characteristic peaks of keratin at 1630 and 1550 cm−1. The releasing performances were examined by ultraviolet and visible spectrophotometry. The results indicated that the ratio between keratin and poly-L-lactide is a major factor to control the sustained-releasing performance. A significant pH sensitivity of the composite nanofibres was achieved after adjusting the operational factors by DoE optimisation. The drug-loaded nanofibres with high content of keratin (50 wt%) released 48.5% of 5-FU in pH 7.4 solution while released 83.7% of 5-FU in pH 6.0 solution. The results indicated that these composite electrospun nanofibres can be used as a candidate of pH-triggered biomaterials. [ABSTRACT FROM AUTHOR]

There is a great need for the progress of composite biomaterials, which are effective for tissue engineering applications. In this work, the development of composite electrospun nanofibres based on polycaprolactone (PCL) and collagen hydrolysate (CH) loaded with ferulic acid (FA) for the treatment of chronic wounds. Response Surface Methodology (RSM) has been applied to nanofibres factor manufacturing assisted by electrospinning. For wound healing applications, the authors have created the efficacy of CH, and PCL membranes can act as a stable, protective cover for wound, enabling continuous FA release. The findings of the RSM showed a reasonably good fit with a polynomial equation of the second order which was statistically acceptable at P < 0.05. The optimised parameters include the quantity of hydrolysate collagen, the voltage applied and the distance from tip‐to‐collector. Based on the Box–Behnken design, the RSM was used to create a mathematical model and optimise nanofibres with minimum diameter production conditions. Using FTIR, TGA and SEM, optimised nanofibres were defined. In vitro, cytocompatibility trials showed that there was an important cytocompatibility of the optimised nanofibres, which was proved by cell proliferation and cell morphology. In this research, the mixed nanofibres of PCL and CH with ferulic could be a potential biomaterial for wound healing. [ABSTRACT FROM AUTHOR]

In this study, we investigated whether the nanofibers produced by natural‐synthetic polymers can probably promote the proliferation of co‐cultured adipose‐derived stem cells/human fibroblast cells (ADSs/HFCs) and synthesis of collagen. Nanofiber was fabricated by blending gelatin and poly (L‐lactide co‐ɛ‐caprolactone) (PLCL) polymer nanofiber (Gel/PLCL). Cell morphology and the interaction between cells and Gel/PLCL nanofiber were evaluated by FESEM and fluorescent microscopy. MTS assay and quantitative real‐time polymerase chain reaction were applied to assess the proliferation of co‐cultured ADSs/HFCs and the collagen type I and III synthesis, respectively. The concentrations of two cytokines including fibroblast growth factor‐basic and transforming growth factor‐β1 were also measured in culture medium of co‐cultured ADSs/HDCs using enzyme‐linked immunosorbent assay assay. Actually, nanofibers exhibited proper structural properties in terms of stability in cell proliferation and toxicity analysis processes. Gel/PLCL nanofiber promoted the growth and the adhesion of HFCs. Our results showed in contact co‐culture of ADSs/HFCs on the Gel/PLCL nanofiber increased cellular adhesion and proliferation synergistically compared to non‐coated plate. Also, synthesis of collagen and cytokines secretion of co‐cultured ADSs/HFCs on Gel/PLCL scaffolds is significantly higher than non‐coated plates. To conclude, the results suggest that Gel/PLCL nanofiber can imitate physiological characteristics in vivo and enhance the efficacy of co‐cultured ADSs/HFCs in wound healing process. [ABSTRACT FROM AUTHOR]

Development of cost‐effective and increasingly efficient sustainable materials for energy‐storage devices, such Li‐ion batteries, is of crucial future importance. Herein, the preparation of carbon nanofibres from biopolymer blends of lignin (byproduct from the paper and pulp industry) and polylactic acid (PLA) or a thermoplastic elastomeric polyurethane (TPU) is described. SEM analysis shows the evolving microstructural morphology after each processing step (electrospinning, stabilisation and carbonisation). Importantly, it is possible to tailor the nanofibre porosity by utilising miscibility/immiscibility rules between lignin and the polymer additive (PLA/TPU). PLA blends (immiscible) generate porous structures whereas miscible lignin/TPU blends are solid when carbonised. Electrodes produced from 50 % PLA blends have capacity values of 611 mAh g−1 after 500 charge/discharge cycles, the highest reported to date for sustainable electrodes for Li‐ion batteries. Thus, this work will promote the development of lignocellulose waste materials as high‐performance energy‐storage materials. [ABSTRACT FROM AUTHOR]

Bridging strategies are required to repair peripheral nerve injuries that result in gaps >5–8 mm. Limitations such as donor‐site morbidity and size mismatches with receptor sites for autografts, together with immunological problems associated with allografts and xenografts, have created an increased interest in the field of manufactured nerve guide conduits. In this study, zein, a plant protein‐based polymer, was electrospun to prepare nanofibrous mats. An important challenge with zein mats is the rapid change from fibre to film under aqueous conditions. Tannic acid (TA), which is a polyphenol, was selected to prepare a blend of zein/TA with different weight ratios to investigate its effect on the wetting resistance of nanofibres. The electrospun mats were characterised and evaluated by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Also, degradation and mechanical properties of the mats were studied. Results showed that TA had a significant effect on the resistance to film formation in nanofibres. Moreover, the degradation and elongation at break of mats were increased with increase in TA concentration. For the investigation of the peripheral nerve regeneration potential, Schwann cells were selected for cytotoxicity evaluation by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5 diphenyltetrazolium bromide assay and cell morphology by SEM. Schwann cells had good biocompatibility with zein/TA blends (%) of 90/10 and 80/20. [ABSTRACT FROM AUTHOR]

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]

Solution processable organic functional materials are highly desirable for device fabrication and applications. The insoluble nature of unsubstituted metal phthalocyanines (MPcs) often limits their applications that demand solution based coating techniques. In this work, nano‐architectures of metal phthalocyanines with important transition metal ions, Mn, Fe, Co, Cu and Zn that are highly dispersible in polar organic solvents have been prepared through a simple chemical route and applied as electrode materials for electrochemical hydrogen evolution reaction (HER). The formation of different MPcs is confirmed through various techniques such as Raman spectrocopy, X‐ray diffraction and X‐ray photoelectron spectroscopy. The morphology of the synthesized MPcs has a fibre‐like structure with varying dimensions of 150–650 nm in width and 5–10 μm in length. These nanostructures are supramolecular self‐assemblies of individual macrocycle rings coming together to form fibre‐like structures through π‐π interactions and are highly ordered with β crystal phase. The obtained CuPc and CoPc nanofibre dispersion coated on to a glassy carbon electrode exhibited an onset potential of −250 and −290 mV and a Tafel slope of 120 and 107 mV dec−1, respectively, for HER and good stability up to 1000 cycles. [ABSTRACT FROM AUTHOR]

Fluorescent markers are critical for tracking the position and movement of molecules both in vivo and in vitro. Conventionally, synthetic dyes are non‐covalently added to polymers for fluorescent tracking, but often diffuse away. Here we demonstrate, for the first time, a facile method for the synthesis of fluorescent poly(lactic acid) nano‐/microfibres for biomedical applications using solution spin blowing. Pyrene‐end‐capped poly(l‐lactide) (PLLA) derivatives were synthesised using the ring‐opening polymerisation of l‐lactide and they were characterised using spectroscopic and thermal analyses. Submicrometre‐sized fluorescent fibres were produced from these PLLA derivatives using solution blow spinning techniques generating polymer blends and core–shell fibres. Such system could be further exploited to incorporate electrically conductive carbon allotropes via the pyrene aromaticity, producing fluorescent and electrically active fibres for in vitro monitoring and electrical stimulation. © 2018 Society of Chemical Industry We present an operationally simple method for the synthesis of pyrene‐tagged polylactides which have been fabricated into fibres using operationally simple solution blow spinning techniques. [ABSTRACT FROM AUTHOR]

Breaking away from the linear structure of previously reported peptide‐based gelators, this study reports the first example of gel formation based on the use of cyclic peptides made of alternating d‐ and l‐amino acids, known to self‐assemble in solution to form long nanotubes. Herein, a library of cyclic peptides was systemically studied for their gelation properties in various solvents, uncovering key parameters driving both organogel and hydrogel formation. The hierarchical nature of the self‐assembly process in water was characterised by a combination of electron microscopy imaging and small‐angle X‐ray scattering, revealing a porous network of entangled nanofibres composed by the aggregation of several cyclic peptide nanotubes. Rheology measurements then confirmed the formation of soft hydrogels. Getting in formation: This study reports the first example of gel formation based on the use of cyclic peptides made of alternating d‐ and l‐ amino acids, which self‐assemble in solution to form long nanotubes. Herein, a library of cyclic peptides was systemically studied for their gelation properties in various solvents, uncovering key parameters driving both organogel and hydrogel formation. [ABSTRACT FROM AUTHOR]

Summary: Repair of ligaments and tendons requires scaffolds mimicking the spatial organisation of collagen in the natural tissue. Electrospinning is a promising technique to produce nanofibres of both resorbable and biostable polymers with desired structural and morphological features. The aim of this study was to perform high‐resolution x‐ray tomography (XCT) scans of bundles of Nylon6.6, pure PLLA and PLLA‐Collagen blends, where the nanofibres were meant to have a predominant direction. Characterisation was carried out via a dedicated methodology to firmly hold the specimen during the scan and a workflow to quantify the directionality of the nanofibres in the bundle. XCT scans with 0.4 and 1.0 μm voxel size were successfully collected for all bundle compositions. Better image quality was achieved for those bundles formed by thicker nanofibres (i.e. 0.59 μm for pure PLLA), whereas partial volume effect was more pronounced for thinner nanofibres (i.e. 0.26 μm for Nylon6.6). As expected, the nanofibres had a predominant orientation along the axis of the bundles (more than 20% of the nanofibres within 3° and more than 60% within 18° from the bundle axis), with a Gaussian‐like dispersion in the other directions. The directionality assessment was validated by comparison against a similar analysis performed on SEM images: the XCT analysis overestimated the amount of nanofibres very close to the bundle axis, especially for the materials with thinnest nanofibres, but adequately identified the amount of nanofibres within 12°. Lay Description: Repair of ligaments and tendons requires dedicated materials (scaffolds) mimicking the spatial organisation of the collagen (the main material composing such natural tissue). Electrospinning is a promising technique that allows production of fibres with nanometric dimension using high voltage to stretch very tiny drops of polymeric solutions. Electrospinning allows processing both polymers that can be resorbed by the host tissue, and nonresorbable ones, to obtain the desired structural and morphological features by arranging the nanofibres in bundles. The aim of this study was to perform high‐resolution x‐ray computed tomography (XCT) scans of bundles, where the nanofibres were meant to have a predominant direction. The investigation included bundles of different compositions: a biostable polymer (Nylon) and bioresorbable ones (pure Poly‐L‐lactic acid (PLLA) and PLLA‐Collagen blends). The electrospun bundles were produced using a validated method (Sensini et al 2017: https://doi.org/10.1088/1758-5090/aa6204). To this end, we developed a dedicated methodology to scan such small specimens, and a workflow to quantify the directionality of the nanofibres in the bundle. For all the compositions, XCT scans with extremely high resolution (i.e. down to 0.4 μm) were successfully collected. As expected, better images were obtained for those bundles where the nanofibres were thicker than the scanning resolution (i.e. 0.59 μm for pure PLLA). The images of the thinnest nanofibres (i.e. 0.26 μm for Nylon) were poorer because the fibre diameter was smaller than the resolution (partial volume effect). The nanofibres had a predominant orientation along the axis of the bundles (more than 60% of the nanofibres were within 18° from the bundle axis). The nanofibres had a Gaussian‐like dispersion in the other directions. As this is the first time that XCT is used to quantify the directionality of this kind of bundles, the directionality assessment was further validated by comparison against a similar analysis performed on SEM images. Overall, this study has demonstrated the usefulness and reliability of using high‐resolution x‐ray computed tomography (XCT) scans to investigate the morphology of polymeric scaffolds made of electrospun nanofibres. [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]

Poly (ɛ‐caprolactone)–chitosan–poly (vinyl alcohol) (PCL: Cs: PVA) nanofibrous blend scaffolds were known as useful materials for skin wound healing and would help the healing process about 50% faster at the final time point. From the previous studies by the authors, PCL: Cs: PVA (in 2: 1: 1.5 mass ratio) nanofibres showed high efficacy in healing on rat models. In this study, the scaffolds were examined in burn and excision wounds healing on dogs as bigger models. The scaffolds were applied on dorsum skin wounds (n = 5) then macroscopic and microscopic investigations were carried out to measure the wounds areas and to track healing rate, respectively. Macroscopic results showed good aspect healing effect of scaffolds compared with control wounds especially after 21 days post‐operating for both cutting and burn wounds. Pathological studies showed that the healing rates of the wounds covered with PCL: Cs: PVA nanofibrous scaffolds were much rapid compared to untreated wounds in control group. The immunogenicity of the scaffolds in canine model was also investigated. The findings showed that nanofibrous blend scaffolds was not immunogenic in humoural immune responses. All these results indicated that PCL: Cs: PVA nanofibrous web could be considered as promising materials for wounds healings. [ABSTRACT FROM AUTHOR]

In this study, the authors report a simple fabrication of thermoplastic polyurethane (TPU) nanofibres‐based kit for cholesterol detection. TPU is a polymer that is highly elastic, resistant to microorganisms, abrasion and compatible with blood; thus, making it a natural selection as an immobilisation matrix for cholesterol oxidase (ChOx) enzyme. The nanofibre was fabricated by electrospinning process and was characterised using scanning electron microscopy and Fourier transform‐infrared spectroscopy. ChOx was covalently immobilised on TPU nanofibre and cholesterol level/concentration was visually found using 4‐aminoantipyrine, a dye that reacts with H2 O2 produced from the oxidation of cholesterol by ChOx and changes colour from yellow to red. The efficacy of the nanofibre to act as a detecting substrate was compared with cellulose acetate (CA) membrane, a well‐documented enzyme immobilisation matrix. The optimisation of enzyme concentration and dye quantity were performed using standard ChOx spectrophotometric assay and the same was used in CA membrane and TPU nanofibre. The ChOx immobilised nanofibre showed good linear range from 2 to 10 mM with a lower detection limit of 2 mM and was highly stable compared to that of CA membrane. The enzyme immobilised nanofibre was further validated in serum samples. [ABSTRACT FROM AUTHOR]

In recent years, carbon aerogels have attracted much attention in basic research and as potential applications in many fields. Herein, the authors report a novel approach using bamboo powder as raw material to fabricate cellulose nanofibers (CNFs)/multi‐walled carbon nanotubes (MWCNTs) carbon aerogels by a simple dipping and carbonisation process. The developed material exhibits many exciting properties including low density (0.056 g cm−3), high porosity (95%), efficient capability for separation of oily droplets from water, and high adsorption capacity for a variety of oils and organic solvents by up to 110 times its own weight. Furthermore, the CNF/MWCNT carbon aerogels (CMCA) can be recycled many times by distillation and combustion, satisfying the requirements of practical oil‐water separation. Taken together with its economical, environmentally benign manufacturing process, sustainability of the precursor and versatility of material, the CMCA developed in this study will be a promising candidate for addressing the problems arising from the spills of oily compounds. [ABSTRACT FROM AUTHOR]

The electrospinning technique was used for the nanofiber production of Alyssum lepidium mucilage with acetic acid and polyvinyl alcohol (PVA) polymer. Some parameters such as voltage, polymer concentration, tip‐to‐collector distance, and feed rate were optimised and applied for the fabrication of the nanofiber membranes of the seeds mucilage. The scanning electron microscopy images were used to find the optimised conditions for the electrospinning process. It was found that the aqueous solution of Alyssum mucilage/PVA (80:20), voltage (18 kV), polymer concentration (50%), tip‐to‐collector distance (10 cm) and feed rate (0.125 ml/h) could be successfully used to obtain uniform nanofibers with diameters as low as 139.9 nm. X‐ray diffraction and Fourier transform infrared spectrometer analysis also proved the presence of the alyssum mucilage/PVA nanofiber. In this study, the used electrospun procedure was biodegradable, inexpensive, non‐toxic, and maintainable enough to optimise the mucilage nanofiber fabrication as a new source, thereby improving the potential application of the nanofiber biomembrane in filtration and medical systems with biocompatible and biodegradable properties. [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]

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. [ABSTRACT FROM AUTHOR]

BACKGROUND Nanotechnology has recently allowed the production of formulations for controlled release of active ingredients. In the present study, the electrospinning technique was used to produce nanoscale dispensers for attract-and-kill strategies. Non-woven nanofibres containing insecticide (cypermethrin) and ( E)-8,( Z)-8-dodecenyl acetate and ( Z)-8-dodecanol (0.87 mg L−1), the main components of Grapholita molesta (Lepidoptera: Tortricidae) (Busck) pheromone, were evaluated in laboratory experiments. Male electroantennographic (EAG) responses and mortality (tarsal-contact and attract-and-kill behavioural cages) bioassays were performed for nanofibres (with and without insecticide) exposed for different periods (21, 42, 63 and 84 days) in controlled and non-exposed conditions. RESULTS There were no significant differences in G. molesta male EAG responses based on the time of exposure within treatments. Nanofibres with pheromone only and with pheromone plus insecticide elicited equal EAG responses. Mortality in tarsal-contact bioassays was greater than 87% after exposure for 84 days. In the attract-and-kill bioassays, mortality ranged from 28.4 to 56.6%, although no difference was observed on insect mortalities over time (24, 48 and 72 h). CONCLUSION Incorporation of cypermethrin in nanofibres did not interfere with G. molesta attractiveness. Both aspects of the strategy, the attractant and killing effects, were recorded using innovative nanofibres, and long-term effects suggest a controlled release of pheromone and insecticide. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Drumstick ( Moringa oleifera) leaves have been used as a folk herbal medicine across many cultures since ancient times. This is most probably due to presence of phytochemicals possessing antioxidant properties, which could retard oxidative stress, and their degenerative effect. The current study deals with nanoencapsulation of Moringa oleifera (MO) leaf ethanolic extract within fish sourced gelatine matrix using electrospinning technique. RESULTS The total phenolic and flavonoid content, radical scavenging (IC50) and metal reducing properties were 67.0 ± 2.5 mg GAE g−1 sample 32.0 ± 0.5 mg QE g−1 extract, 0.08 ± 0.01 mg mL−1 and 510 ± 10 µmol eq Fe(II) g−1 extract, respectively. Morphological and spectroscopic analysis of the fibre mats confirmed successful nanoencapsulation of MO extract within defect free nanofibres via electrospinning process. The percentage encapsulation efficiency (EE) was between 80% and 85%. Furthermore, thermal stability of encapsulated fibres, especially at 3% and 5% of core loading content, was significantly improved. Toxicological analysis revealed that the extract in its original and encapsulated form was safe for oral consumption. CONCLUSION Overall, the present study showed the potential of ambient temperature electrospinning process as a safe nanoencapsulation method, where MO extract retained its antioxidative capacities. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The search for an optimal aortic valve implant with durability, calcification resistance, excellent haemodynamic parameters and ability to withstand mechanical loading is yet to be met. Thus, there has been struggled to fabricate bio‐prosthetics heart valve using bioengineering. The consequential product must be resilient with suitable mechanical features, biocompatible and possess the capacity to grow. Defective heart valves replacement by surgery is now common, this improves the value and survival of life for a lot of patients. The recent paediatric heart valve implant is suboptimal due to their inability of somatic growth. They usually have multiple surgeries to change outgrown valves. Short‐lived valve bio‐prostheses occurring in older patients and younger ones who more usually need the replacement of its damaged heart with prosthesis led to a new invasive surgical interventions with an improved quality of life. The authors propose that nanofibre scaffold for paediatric tissue‐engineered heart valve will meet most of these conditions, most particularly those related to somatic growth, and, as the nanofibre scaffold is eroded, new valve is produced, the valve matures in the child until adulthood. [ABSTRACT FROM AUTHOR]

The interesting characteristics of electrospun nanofibres, such as high surface-to-volume ratio, nanoporosity, and high safety, make them suitable candidates for use in a variety of applications. In the recent decade, electrospun nanofibres have been applied to different potential fields such as filtration, wound dressing, drug delivery, etc. and a significant number of review papers have been published in these fields. However, the use of electrospun nanofibres in agriculture is comparatively novel and is still in its infancy. In this paper, the specific applications of electrospun nanofibres in agriculture and food science, including plant protection using pheromone-loaded nanofibres, plant protection using encapsulation of biocontrol agents, preparation of protective clothes for farm workers, encapsulation of agrochemical materials, deoxyribonucleic acid extraction in agricultural research studies, pre-concentration and measurement of pesticides in crops and environmental samples, preparation of nanobiosensors for pesticide detection, encapsulation of food materials, fabrication of food packaging materials, and filtration of beverage products are reviewed and discussed. This paper may help researchers develop the use of electrospun nanofibres in agriculture and food science to address some serious problems such as the intensive use of pesticides. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Chitosan‐poly (vinyl alcohol) (Cs: PVA) (2:3) and poly (caprolactone)‐chitosan‐poly (vinyl alcohol) (PCL: Cs: PVA) (2:1:1.5) nanofibrous blend scaffolds were fabricated using the electrospinning technique in the authors' previous studies. The results of the previous studies confirmed the high biological properties of the scaffolds and their ability in healing of burn and excision wounds on rat model. In the present study, the biological scaffolds were applied on diabetic dorsum skin wounds and diabetic foot wound on rat models (n = 16). Macroscopic and microscopic investigations were carried out using digital images and haematoxylin and eosin (H&E) staining respectively, to measure the wound areas and to track wound healing rate. It was found that at all time points the areas of wounds treated with nanofibrous scaffolds were smaller compared with the controls. Pathological results showed much better healing efficacy for the test samples compared with the control ones. Pathological investigations proved the presence of more pronounced granulation tissues in the scaffold‐treated wounds compared with the control ones. At 20 days post excision, the scaffold‐treated groups achieved complete repair. The results indicated that Cs: PVA and PCL: Cs: PVA nanofibrous webs could be considered to be promising materials for burn, excision and diabetic wounds healing. [ABSTRACT FROM AUTHOR]

Aim To evaluate both the drug-release profile and the effects on human dental pulp stem cells' (h DPSC) proliferation and viability of novel bi-mix antibiotic-containing scaffolds intended for use as a drug delivery system for root canal disinfection prior to regenerative endodontics. Methodology Polydioxanone ( PDS)-based fibrous scaffolds containing both metronidazole ( MET) and ciprofloxacin ( CIP) at selected ratios were synthesized via electrospinning. Fibre diameter was evaluated based on scanning electron microscopy ( SEM) images. Pure PDS scaffolds and a saturated CIP/MET solution ( i.e. 50 mg of each antibiotic in 1 mL) (hereafter referred to as DAP) served as both negative (nontoxic) and positive (toxic) controls, respectively. High-performance liquid chromatography ( HPLC) was performed to investigate the amount of drug(s) released from the scaffolds. WST-1® proliferation assay was used to evaluate the effect of the scaffolds on cell proliferation. LIVE/DEAD® assay was used to qualitatively assess cell viability. Data obtained from drug release and proliferation assays were statistically analysed at the 5% significance level. Results A burst release of CIP and MET was noted within the first 24 h, followed by a sustained maintenance of the drug(s) concentration for 14 days. A concentration-dependent trend was noticed upon h DPSCs' exposure to all CIP-containing scaffolds, where increasing the CIP concentration resulted in reduced cell proliferation ( P < 0.05) and viability. In groups exposed to pure MET or pure PDS scaffolds, no changes in proliferation were observed. Conclusions Synthesized antibiotic-containing scaffolds had significantly lower effects on h DPSCs proliferation when compared to the saturated CIP/MET solution ( DAP). [ABSTRACT FROM AUTHOR]

In this work, N, O‐carboxymethyl chitosan (CMCS) samples from virgin chitosan (CS) were synthesised and CMCS/polyethylene oxide (PEO) (50/50) blend nanofibrous samples were successfully electrospun from their aqueous solution. The electrospinning conditions to achieve smooth and fine diameter nanofibrous mats were optimised via D‐optimal design approach. Afterwards, vitamin C and phenytoin sodium (PHT‐Na) were added to these samples for producing wound dressing materials. H‐nuclear magnetic resonance, scanning electron microscopy and Fourier transform infrared tests for the evaluation of functionalised CS, morphology and biodegradability studies of CMCS/PEO blend nanofibrous samples were applied. The kinetic and drug release mechanism for vitamin C and PHT‐Na drug‐loaded electrospun samples were also investigated by UV‐vis spectrophotometer and high performance liquid chromatography, respectively. The results showed an approximately similar drug release rate of the two drugs and followed Higuchi's kinetic model. The stem cells viability and their adhesion on the surface of the samples containing PHT‐Na and vitamin C were carried out using MTT assay and the best cells' biocompatibility was obtained using both drugs into the CMCS/PEO nanofibrous samples. Moreover, the in vivo animal wound model results revealed that the electrospun samples containing vitamin C and PHT‐Na (1%) had a remarkable efficiency in the wounds' closure and their healing process compared with vitamin C/PHT‐Na (50/50) ointment. Finally, the histology observations showed that the wound treated with optimised electrospun samples containing two drugs enabled regeneration of epidermis layers due to collagen fibres accumulation followed by granulating tissues formation without necrosis. [ABSTRACT FROM AUTHOR]

Highly porous Si/TiO2 composite nanofibres were prepared using a unique sulphur-templating method combined with electrospinning. The structure, morphology, surface area, phase and composition of these nanofibres were characterized using Raman spectroscopy, scanning electron microscopy, powder X-ray diffraction, surface area analyser and thermogravimetric analyser. The specific surface area of Si/TiO2 porous NFs is as large as 387 m2 g−1, whose silicon capacity can be maintained above 1580 mAh g−1 in 180 cycles. [ABSTRACT FROM AUTHOR]

The study was aimed at evaluating the effect of electrospun scaffold containing TGF‐β1 on promoting human mesenchymal stem cells (MSCs) differentiation towards a nucleus pulposus‐like phenotype under hypoxia. Two kinds of nanofibrous scaffolds containing TGF‐β1 were fabricated using uniaxial electrospinning (Group I) and coaxial electrospinning (Group II). Human MSCs were seeded on both kinds of scaffolds and cultured in a hypoxia chamber (2% O2), and then the scaffolds were characterised. Cell proliferation and differentiation were also evaluated after 3 weeks of cell culture. Results showed that both kinds of scaffolds shared similar diameter distributions and protein release. However, Group I scaffolds were more hydrophilic than that of Group II. Both kinds of scaffolds induced the MSCs to differentiate towards the nucleus pulposus‐type phenotype in vitro. In addition, the expression of nucleus pulposus‐associated genes (aggrecan, type II collagen, HIF‐1α and Sox‐9) in Group I increased more than that of Group II. These results indicate that electrospinning nanofibrous scaffolds containing TGF‐β1 supports the differentiation of MSCs towards the pulposus‐like phenotype in a hypoxia chamber, which would be a more appropriate choice for nucleus pulposus regeneration. [ABSTRACT FROM AUTHOR]

ABSTRACT The present work reports the fabrication of a fragrance delivery system using nanofibres by an electrospinning method. Fragrant oils are volatile essential oils that easily undergo degradation and evaporation. Nanostructured fibres of poly(vinyl alcohol) (PVA) and poly( ε-caprolactone) (PCL) were prepared by an electrospinning process. In this study, l-carvone was used as a model fragrant oil, and it can be used as an air-freshening agent. l-carvone (5 wt%) loaded PVA solution (10 wt%) (C-PVA) and PCL solution (13 wt%) (C-PCL) were electrospun into nanofibres. The scanning electron microscopy (SEM) images showed that the incorporation of essential oil l-carvone in PVA and PCL solution caused the resulting as-spun fibre to be non-uniform, and the average diameter was found to increase from 100-190 nm to 230-400 nm for the PVA mat and from 300-500 nm to 390-800 nm for the PCL mat. The functional group, crystallinity and thermal stability of prepared electrospun nanofibres were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) measurements. The degree of crystallinity of electrospun PVA, C-PVA, PCL and C-PCL was found to be 10.46%, 7.4%, 56.16% and 53.41% respectively. The in vitro release of l-carvone from the prepared electrospun fibres was conducted at 30 ± 0.2°C for 24 h by both the encapsulation and imbibition methods. The maximum release of l-carvone (5 wt%) was observed to be 61% and 64.1% from PVA nanofibres and 36% and 48.4% from PCL nanofibres by the encapsulation and imbibition methods respectively. These results show the potential of the prepared electrospun l-carvone-loaded PVA and PCL nanofibrous membrane in the fragrance delivery system. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Electrospinning of various polymers has been used to produce nanofibrous scaffolds that mimic the extracellular matrix and support cell attachment for the potential repair and engineering of nerve tissue. In the study reported here, an electrospun copolymer of l-lactide and ε-caprolactone (67:33 mol%) resulted in a nanofibrous scaffold with average fibre diameter and pore size of 476 ± 88 and 253 ± 17 nm, respectively. Blending with low loadings of collagen (<2.5% w/w) significantly reduced the average diameter and pore size. The uniformity of fibre diameter distributions was supported with increasing collagen loadings. The nanofibrous scaffolds significantly promoted the attachment and proliferation of olfactory ensheathing cells compared to cells exhibiting asynchronous growth. Furthermore, analysis of cell health through mitochondrial activity, membrane leakage, cell cycle progression and apoptotic indices showed that the nanofibrous membranes promoted cell vigour, reducing necrosis. The study suggests that the use of more cost-effective, low loadings of collagen supports morphological changes in electrospun poly[( l-lactide)- co-( ε-caprolactone)] nanofibrous scaffolds, which also support attachment and proliferation of olfactory ensheathing cells while promoting cell health. The results here support further investigation of the electrospinning of these polymer blends as conduits for nerve repair. © 2013 Society of Chemical Industry [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]

Fibres with diameters less than 1000 nm (or 1 µm) are defined as nanofibres and they can be produced by several processing techniques, particularly by electrospinning (ES) technique. ES technique was invented by Formhals in 1934 that in this the electrical field imposes a uniaxial stretching of a viscoelastic jet derived from the polymer solution to continuously reduce the diameter and leads to formatting nanofibres. It is simple and cost‐effectiveness technique for preparation of nanofibres. Electrospinning allows for fabricating polymer fibres with diameters varying from 3 nm to greater than 5 µm and in the past decade due in large part to a higher interest in nanoscale properties and technologies. In synthesis process of nanofibres by ES technique, many factors affect on the synthetic nanofibres properties such as polymer properties, solvent properties, additives, polymer concentration, solution properties and so on. In this study, the authors reviewed basic electrospinning and introduces various polymers for preparation of nanofibres. [ABSTRACT FROM AUTHOR]

Decomposition of a cellulose fleece in nanofibrils with diameters ranging from several nm to around 30 nm could be realized by establishing a two-step process: the dispersion in sodium hydroxide solution followed by a mechanical dissociating step. This is supported by the crystal structure analysis, which indicates, with a refined crystallite size in the range of the fibril diameter, the decomposition of the cellulose in nanofibrils. The fiber length was largely preserved. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) has been exploited for coating γ-alumina nanofibres with amorphous alumina, using trimethylaluminium Al(CH3)3 (TMA) and water as precursors. The experiments were carried out at 150 or 300 °C, using 100 cycles (or an integer multiple of it) of ALD treatment. Heat-treatment was applied to the fibres to evaluate possible changes in ALD process development. Some samples were compacted and hardness was measured to preliminarily evaluate the effect of ALD and possible usage of fibres as raw material for hard ceramics. X-ray absorption spectroscopy, X-ray diffraction, scanning electron microscopy (SEM) and Vickers hardness test were used to characterize the fibres (with and without ALD coating). Alumina nanofibres can be considered as reinforcements in structural composites or as a material for inorganic membranes, suitable to applications at elevated temperatures. [ABSTRACT FROM AUTHOR]

Small-molecule fluorescent sensors ( 1- 5) for the recognition of nitroaromatic compounds, such as 2,4-dinitrotoluene and the explosive TNT, were obtained by using a three-step dehydrohalogenation cycloaddition protocol. The interaction of the receptors and nitroaromatics was studied both in solution and in the solid state by using fluorescence spectroscopy and X-ray crystallography, respectively. It is shown that the iptycene receptors 1- 5 provide a cavity suitable for binding nitroaromatic compounds in an edge-to-face mode, rather than simple ring-stacking interactions. The results obtained inspired us to develop an inexpensive, reliable and robust sensor for vapour detection of explosives. Polymer nanofibres are particularly suitable for the production of such TNT sensors as they accelerate the mass exchange between the polymer and the vapours of TNT. Quenching of the sensors took place within 1 min compared to 10 min for a glass-slide assay. Hence, the sensor performance can be improved by optimising the matrix material and morphology without resynthesising the sensor moieties. [ABSTRACT FROM AUTHOR]

Poly-(3-hexylthiophene) (P3HT) has been applied in many fields such as organic solar cells, printed electronic circuits, due to superior semiconducting properties compared to other semiconducting polymers. The presence of π-π interaction causes regio-regular P3HT to form ordered lamellar stacks during crystallisation. Here we report a simple room temperature, solution based method to synthesise P3HT nanofibres with controllable sizes. Our method is based on differing solubility of P3HT in various solvents. In a mixed solvent environment, we could control the precipitation of P3HT to obtain nanofibres with various diameters by varying the ratios of the solvents. We found that the lengths of the nanofibres could be controlled with concentration of the solution. Other methods to obtain nanofibres of P3HT invariably involves heating and controlled cooling which makes reproducibility and morphology control difficult. Furthermore, we synthesised a nanocomposite consisting of P3HT nanofibres and quasi-type-II quantum dots and evaluated the photoelectric properties of the nanofibres as well as the nanocomposites using interdigitated gold microelectrodes (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

1. Curcumin is a naturally occurring poly-phenolic compound with a broad range of favourable biological functions, including anti-cancer, anti-oxidant and anti-inflammatory activities. The low bioavailability and in vivo stability of curcumin require the development of suitable carrier vehicles to deliver the molecule in a sustained manner at therapeutic levels. 2. In the present study, we investigated the feasibility and potential of poly(caprolactone) (PCL) nanofibres as a delivery vehicle for curcumin for wound healing applications. By optimizing the electrospinning parameters, bead-free curcumin-loaded PCL nanofibres were developed. 3. The fibres showed sustained release of curcumin for 72 h and could be made to deliver a dose much lower than the reported cytotoxic concentration while remaining bioactive. Human foreskin fibroblast cells (HFF-1) showed more than 70% viability on curcumin-loaded nanofibres. 4. The anti-oxidant activity of curcumin-loaded nanofibres was demonstrated using an oxygen radical absorbance capacity (ORAC) assay and by the ability of the fibres to maintain the viability of HFF-1 cells under conditions of oxidative stress. 5. The curcumin-loaded nanofibres also reduced inflammatory induction, as evidenced by low levels of interleukin-6 release from mouse monocyte–macrophages seeded onto the fibres following stimulation by Escherichia coli-derived lipopolysaccharide. 6. The in vivo wound healing capability of the curcumin loaded PCL nanofibres was demonstrated by an increased rate of wound closure in a streptozotocin-induced diabetic mice model. 7. These results demonstrate that the curcumin-loaded PCL nanofibre matrix is bioactive and has potential as a wound dressing with anti-oxidant and anti-inflammatory properties. [ABSTRACT FROM AUTHOR]

Inadequate cell numbers in culture is one of the hurdles currently delaying the application of human embryonic stem cells (hESCs) for transplantation therapy. Nanofibrous scaffolds have been effectively used to expand and differentiate non-colony forming multipotent mesenchymal stem cells (MSC) for the repair of tissues or organs. In the present study, we evaluated the influence of nanofibrous scaffolds for hESC proliferation, increase in colony formation, self-renewal properties, undifferentiation and retention of ‘stemness’. Polycaprolactone/collagen (PCL/collagen) and PCL/gelatin nanofibrous scaffolds were fabricated using electrospinning technology. The hESCs were seeded on the nanofibrous scaffolds in the presence or absence of mitomycin-C treated mouse embryonic fibroblasts (MEFs). The hESCs grown on both scaffolds in the presence of the MEFs produced an increase in cell growth of 47.58% ( P≤ 0.006) and 40.18% ( P≤ 0.005), respectively, over conventional controls of hESCs on MEFs alone. The hESC colonies were also larger in diameter on the scaffolds compared to controls (PCL/collagen, 156.25 ± 7 μM and PCL/gelatin, 135.42 ± 5 μM). Immunohistochemistry of the hESCs grown on the nanofibrous scaffolds with MEFs, demonstrated positive staining for the various stemness-related markers (octamer 4 [OCT-4], tumour rejection antigen-1–60, GCTM-2 and TG-30), and semi-quantitative RT-PCR for the pluripotent stemness genomic markers (NANOG, SOX-2, OCT-4) showed that they were also highly expressed. Continued successful propagation of hESC colonies from nanofibrous scaffolds back to conventional culture on MEFs was also possible. Nanofibrous scaffolds support hESC expansion in an undifferentiated state with retention of stemness characteristics thus having tremendous potential in scaling up cell numbers for transplantation therapy. [ABSTRACT FROM AUTHOR]

A systematic investigation of the hyperpolarisabilities of substituted p-poly-phenylenes is presented using different quantum mechanical approaches, including density functional theory and Møller–Plesset (MP2) methods. A medium-sized basis set Hartree–Fock (HF) hyperpolarisability calculation based on either a density functional theory (DFT) or MP2 geometry gives reliable results at moderate computational costs when comparing with experimental data. A longer phenylene chain leads to a maximum in the per-unit increase of the investigated property between 3 and 4 repeat units. Changing the underlying geometry from the minimum helix to a planar orientation leads to a significant increase in β, again dependent on the chain length. Terminal para-substituents and their influence are studied and categorised. For push–pull groups, the substituent effects are mainly additive, allowing the design of functionalised phenylenes as molecular building blocks for nanofibres with tailored nonlinear optical (NLO) properties. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride nanosheet (i.e., g‐C3N4) is identified as a suitable graphene analogue due to its high theoretical capacity, wider and vacant structure, and easy synthesis method. Currently, g‐C3N4 nanosheet has limited application in lithium‐ion batteries (LIBs) which is mainly due to the lack of effective intercalation/deintercalation reaction sites, the high binding energy of the Li to the nanosheet, and insufficient conductivity and stability. Density functional theory calculation predicts that the edges of g‐C3N4 fibre have a suitable adsorption energy and bestow a balanced adsorption force and desorption freedom to Li. In order to verify this prediction, g‐C3N4 nanofibre is synthesized with the edges and pores, as well as higher pyridinic nitrogen content, using a simple polymerization/polycondensation method. The as‐prepared g‐C3N4 fibre delivers a remarkable specific capacity of 181.7 mAh g−1, as well as extraordinary stability and power density. At a high rate of 10C, the g‐C3N4 fibre still has a specific capacity of 138.6 mAh g−1 even after 5000 cycles, being the best‐performing g‐C3N4 electrode so far in literature. This work is exemplary in combining theoretical computing and experimental techniques in designing the next generation of electroactive materials for LIBs. A g‐C3N4 fibre structure with edges and low graphitic nitrogen content is developed as an anode material for lithium‐ion batteries. The g‐C3N4 fibre structure delivered an ultrahigh specific capacity of 181.7 mAh g−1 after 200 cycles at 0.5 C and 138.6 mAh g−1 at 10C with an exceptional long life of 5000 cycles. [ABSTRACT FROM AUTHOR]