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Abstract In this work, catalytic Cr metal overlayered TiO 2 /ITO nanocomposite films were synthesized by novel two step deposition using spray pyrolysis and electron beam evaporation and optimized for use as H 2 sensors. The Cr stimulated TiO 2 /ITO sensor showed well-defined crystalline (101) TiO 2 anatase phase with crystallite size in the range 12–14 nm. The band gap energy could be tuned from 2.44 eV to 2.06 eV, when the thickness of Cr stimulating layer increased. The anatase phase of the nanocomposites was further confirmed by Raman spectroscopy. The nanospheres shaped grains with porous morphology of the film prepared for 10 min Cr deposition time is beneficial to enhance the gas sensing activity at room temperature. The nanocomposite sensor with different Cr overlayer thickness modified the TiO 2 microstructure due to spillover effect and revealed improvement in sensitivity. The Cr:TiO 2 /ITO sensor prepared with the Cr deposition time of 10 min recorded a fast response and recovery time of 30 s and 20 s, respectively, even at room temperature. Highlights • Room temperature hydrogen sensing performance of hybrid Cr:TiO 2 /ITO nanocomposite was studied. • Different Cr deposition time played a major role on the properties of the sensor. • SEM revealed a nanospherical morphology for the hybrid Cr/TiO 2 /ITO. • High sensor response and fast recovery was recorded even at low H 2 concentration. [ABSTRACT FROM AUTHOR]

Highlights • Ru nanoparticles can be predicated in amorphous thin films by electron irradiation. • Induced electric field can reduce the Gibbs free energy barrier of metal particles. • Ion drifting driven by electric forces affect kinetic process of nucleation. • The induced electric field originates from charging effect in (S)TEM. [ABSTRACT FROM AUTHOR]

This study experimentally and analytically examined the influence of carbon nanofiber (CNF) z-threads on the through-thickness (i.e., z-direction) thermal conductivity of unidirectional carbon fiber reinforced plastics (CFRPs). It was hypothesized that a network of CNF z-threads within CFRPs would provide a thermally conductive microstructure throughout the sample thickness that would increase the through-thickness thermal conductivity. The experiments showed that the through-thickness thermal conductivity of the CNF z-threaded CFRPs (9.85 W/m-K) was approximately 7.53 times greater than that of the control CFRPs (1.31 W/m-K) and 2.73 times greater than that of the unaligned CNF-modified CFRPs (3.61 W/m-K). Accordingly, the CNF z-threads were found to play a substantial role in increasing the through-thickness thermal conductivity of CFRPs. To better understand the role of the CNF z-threads in through-thickness thermal transport, simple logical models of the CFRPs were constructed and then compared with the experimental results. Through these analyses, it was determined that CNF z-threads substantially enhance the through-thickness thermal conductivity by creating carbon fiber-CNF linkages throughout the CFRP laminate; these linkages allow the heat flow to largely bypass the resistive resin that envelops the carbon fibers. In addition, thermal infrared tests illustrated that the increased through-thickness thermal conductivity of the CNF z-threaded CFRP enabled the location and visualization of defects within the laminate, which was not possible with the control CFRP. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New structure of composite fibre-on-fibre morphology TiO 2 catalytic layer was formed. • Superb photocatalytic activity of composite was monitored with lower amounts of catalyst. • High potential for photocatalytic application in different environmental systems is declared. Abstract Titanium dioxide in different forms such as films, fibres or particles are being extensively studied due to its excellent photocatalytic activity for decomposition of variety organic pollutants. 1-D structured fibrous TiO 2 is getting more attention as an attractive candidate for practical applications due to its morphological advantages. This paper describes the production and characterization of supported TiO 2 nanofibrous layers, produced by electrospinning process on different supports. A photocatalytic active anatase phase within fibres was obtained, with relatively high specific surface are of 83.9 m2/g. A novel organic–inorganic hybrid catalyst with rough and branchy structure is reported. The photocatalytic performance of the processed samples was measured by following the degradation of organic pollutants in aqueous and air media. The notable photocatalytic activity shows that the composite samples can be competitive catalyst media based on structural properties and the degradation efficiency of several organic pollutants. [ABSTRACT FROM AUTHOR]

Abstract A woven nanotextile implant was developed and optimized for long-term continuous drug delivery for potential oncological applications. Electrospun polydioxanone (PDS) nanoyarns, which are twisted bundles of PDS nanofibres, were loaded with paclitaxel (PTX) and woven into nanotextiles of different packing densities. A mechanistic modeling of in vitro drug release proved that a combination of diffusion and matrix degradation controlled the slow PTX-release from a nanoyarn, emphasizing the role of nanostructure in modulating release kinetics. Woven nanotextiles, through variations in its packing density and thereby architecture, demonstrated tuneable PTX-release. In vivo PTX-release, pharmacokinetics and biodistribution were evaluated in healthy BALB/c mice by suturing the nanotextile to peritoneal wall. The slow and metronomic PTX-release for 60 days from the loosely woven implant was extremely effective in enhancing its residence in peritoneum, in contrast to intraperitoneal injections. Such an implantable matrix offers a novel platform for therapy of solid tumors over prolonged durations. Graphical Abstract Nanotextiles woven from electrospun nanofibrous yarns as suturable intraperitoneal drug depots offer an excellent platform for loading chemodrugs like Paclitaxel to provide tuneable and metronomic drug release in a slow sustained manner over prolonged time intervals, in the peritoneum. Unlabelled Image [ABSTRACT FROM AUTHOR]

Lignin/poly(vinyl alcohol) (PVA) nanocomposite fibers with different lignin concentrations were developed via electrospinning to investigate further possible applications of lignin, an under-utilized renewable biomass material. The antimicrobial and ultraviolet (UV) absorption properties of lignin/PVA nanocomposite fibers were evaluated to determine whether the inherent functionalities of lignin remain in the final material. An environmentally benign crosslinking method was sought to increase the stability of lignin/PVA nanocomposite fibers in aqueous media. The crosslinking and insolubilization of the lignin/PVA nanocomposite fibers was achieved by combining several crosslinking techniques: water vapor treatment at 80℃ for 180 min, photo-irradiation for 30 min under visible light at a distance of 17 cm, and heat treatment at 200℃ for 60 min. Both lignin/PVA nanocomposite fiber webs—containing 50 and 85 wt% of lignin at a 3.0 g/m2 web area density, respectively—showed a 99.9% reduction rate against Staphylococcus aureus, but no reduction against Escherichia coli. The same systems exhibited ultraviolet protection factors (UPF) of >50, indicating excellent UV protection. These findings demonstrate the potential of lignin-based composite fibers, and may widen the range of applications for this biomass material. [ABSTRACT FROM AUTHOR]

To study the release behavior and the existing position of Domiphen® in its its complexed poly-L-lactic acid (PLLA) micro-fibers, two series of fibrous films were prepared by electrospinning solution and W/O emulsion, which was added to Domiphen® directly and emulsified by Domiphen®, respectively, by complexing methods. The mass ratio of Domiphen® to PLLA was 0.25%, 0.5%, 0.75%, and 1% for both methods. According to the scanning electron microscopic observation, W/O emulsion and fibers of narrow-distributed diameters were obtained by W/O emulsion electrospinning. Fluorescence microscopic observation suggested that Domiphen® was incorporated within fibers by W/O emulsion electrospinning. X-ray diffraction and differential thermal analysis characterization suggested that Domiphen® complexed well with PLLA according to noncrystalline Domiphen® existing within and on PLLA fibers prepared by both methods. Domiphen® release curves were prepared and fitted after the amount of Domiphen® released from the PLLA fibers was determined by high-performance liquid chromatography. It was discovered that, with regard to the fibrous films prepared by homogeneous solution electrospinning, Domiphen® released from fibers in accordence with the Freundlich's equation suggesting that Domiphen® almost existed within the outermost border of the fiber cross section and its release behavior could be considered as the counter adsorption process, while with regard to the fibers prepared by W/O emulsion electrospinning, the release curves were S shape under the effect of proteinase K degradation and could be fitted to the corrosion-mechanism Peppas' equation of n value >0.5, which suggested that Domiphen® existed both on the surfaces in small proportion and the inner border of the core-sheath fibers in big proportion. [ABSTRACT FROM AUTHOR]

Abstract Formation of single fibres of polymer nanocomposite PVDF-HFP containing MWCNT by Pyro-EHD electrospinning is reported for the first time. Pyro-EHD gives the chance to drawing fibres directly from a viscous polymeric solution containing MWCNT, with respect to classical electrospinning in which highly viscous materials have strong limitation due to the clogging effect. This method allows achieving an electrical conductivity of the fibres considerably higher with respect to the bulk state. The improvement of the electrical conductivity is of one order of magnitude and the electrical percolation threshold is reduced from 2.5 to 0.3 wt%. We also show that the MWCNT are highly oriented in the longitudinal direction of the fibres, producing the improvement in the electrical properties of the composite. Graphical abstract Image Highlights • Pyro-electrospinning is used to produce nanocomposite microfibres. • Fibres electrical percolation threshold is lowered respect to films. • Carbon nanotubes are highly oriented in the longitudinal direction of the fibres. [ABSTRACT FROM AUTHOR]

Abstract The polymerization of aniline (AN) was assisted with an oligomer that possessed two amino end groups (2AO) in the presence of a single enantiomeric acid, (1 S)-(+)-10-camphorsulfonic acid ((S) CSA). The reaction produced helical polyaniline (PANI) nanofibers with the opposite helical sense due to the concentration changes of (S) CSA in the polymerization system. The similar dependence of the circular dichroism (CD) signal on the (S) CSA concentration was also observed in the oxidization of the oligomer 2AO by ammonium persulfate (APS) in the presence of (S) CSA. In addition, under a certain (S) CSA concentration, the 2AO- assisted polymerization at low and high temperatures also produced the PANI fibers with the opposite helical sense. It is likely that these result from the different interaction modes of (S) CSA with the 2AO at different (S) CSA concentration. As a consequence, the oxidized 2AO (oligomer seeds) with different chirality in the early stage of the polymerization control the helicity of the resulting PANI nanofibers. Graphical abstract Polymerization of aniline assisted by an aniline oligomer having two amino end groups (2AO) in the presence of a single enantiomeric acid ((S) CSA) produced the helical PANI nanofibers with the opposite helical sense due to the concentration changes of (S) CSA in the polymerization system. Image 1 Highlights • The handedness of PANI nanofibers was triggered by the concentration of (S) CSA. • The effects of the oligomer's chirality on the resulting PANI were investigated. • The handedness of PANI nanofibers was triggered by polymerization temperature. • The interaction mode of (S) CSA with the oligomer controls the chirality of PANI. [ABSTRACT FROM AUTHOR]

Abstract A self-standing filter with a porosity of 80% is prepared from naturally abundant cellulose biopolymer in its native state by water-based cationization and freeze-drying processes. The positive surface charge of the filter in a wide pH range favors its interaction with various nanoparticles (NPs), while its tortuous sheet structure builds a contact between cellulose nanofibers (CNF) and the NPs, and hinders them to pass through the filter. Unlike membranes used for the retention of NPs and viruses, the separation in the CNF filter is not only limited to its surface but occurs also in its interior even when the NPs are orders of magnitude smaller than the filter pores. Additional functionalities added to the filter enlarge the spectrum of NPs it can separate. NPs supported onto the filter can thereafter be utilized for the reduction of harmful chemicals into their benign form. The present filter concept may not only address shortcomings of the current membrane systems, but could offer a disruptive technology for the sustainable and universal water purification. [ABSTRACT FROM AUTHOR]

Abstract It is universal to repair abdominal wall defects with prosthetic materials in abdominal surgery worldwide, which are associated with high complications and organ damage. At present, the composite nanofibers composed of natural and synthetic polymers as the new type of nano structure scaffold have attracted considerable attention in the field of tissue engineering. In this study we examined the feasibility of using electrospun silk fibroin (SF)/poly (3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) hybrid scaffolds for repairing of abdominal wall defects. Both in vivo and in vitro characterization were evaluated to access efficacy of the nanofiber for tissue regeneration. Our results showed that the electrospun SF/PHBV nanofiber scaffolds could stimulate the expression of TGF-β1 and Collagen I in fibroblasts in vitro and then promote granulation and connective tissue depositions, but not result in a strong foreign body reaction in vivo. Moreover, we conjectured the potential molecular biological mechanism of SF/PHBV hybrid scaffolds in the process of tissue regeneration. Thus, the SF/PHBV hybrid nanofiber scaffolds have high efficiency and biocompatibility to repair abdominal wall defects. Highlights • Abdominal wall defects affect millions of people around the world in recent years and the number is still rising. • Repairing abdominal wall defects with prosthetic materials is associated with high complications and organ damage. • The electrospun silk fibroin (SF)/poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) hybrid scaffolds were studied. • Both in vivo and in vitro characterization were evaluated to access efficacy of the nanofiber for tissue regeneration. • SF/PHBV hybrid nanofiber scaffolds had high efficiency and biocompatibility to repair abdominal wall defects. [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]

We report the magnetic and transport properties of polycrystalline Nd0.58-xGdxSr0.42MnO3 (x~0.0, 0.04, 0.08, 0.12, 0.16, 0.20, 0.25, 0.30, 0.35, and 0.42). All the samples are single phase and have grain size ~1-2 μm. As the variance σ2 increases, the paramagnetic-ferromagnetic transition shows a gradual decrease and broadening, while the decrease in insulator metal transition is sharpened. However, near equality of TC and TIM at intermediate values of σ2 could be understood in terms of the competing quenched and the grain boundary disorder. The variation in peak magnetoresistance (MR) (maximum MR around TC/TIM) with σ2 shows that maximum low field MR≈35% at H=3 kOe) 68% at H=10 kOe) is centered around σ2=0.009 857 Å2 (x=0.25). This shows that huge intrinsic MR can be obtained at relatively higher temperatures and lower magnetic fields in the region of enhanced phase fluctuations. [ABSTRACT FROM AUTHOR]

We report studies on exchange bias effects in Ni-NiO nanoparticles with different particle diameters/distributions and concentration of metallic nickel, which vary from 0% to 32%. The exchange bias field, Hex, depends strongly upon both particle size and the concentration of metallic Ni, being maximum (~2.2 kOe) at 5 K for the sample with almost negligible concentration of metallic Ni, whereas the corresponding value for the sample with highest concentration of metallic Ni (~32±5.0%) is about 0.07 kOe. The structural features of the samples have been investigated thoroughly by using the Reitveld refinement of x-ray diffraction data and high resolution transmission electron microscopy, where as the magnetic properties using superconducting quantum interference device magnetometer. [ABSTRACT FROM AUTHOR]

Ti nanoparticles were produced using a cluster-deposition method. Ti:TiO core-shell structures were fabricated by partially oxidizing the surface of the Ti nanoparticles produced by a cluster-deposition system via multistep annealing at 250°C in oxygen. X-ray diffraction and transmission-electron microscopy studies reveal an increase in the thickness of the TiO shell with increasing annealing time. The magnetic moment and the coercivity of the core-shell nanoparticles increase with the TiO shell thickness, which is consistent with homogenous bulk defects in TiO. The core-shell nanoparticles display an abnormal hysteresis loop, which probably reflects a combination of antiferromagnetic exchange and magnetocrystalline anisotropy. [ABSTRACT FROM AUTHOR]

We report the magnetic and transport properties of polycrystalline Nd0.58-xGdxSr0.42MnO3 (x~0.0, 0.04, 0.08, 0.12, 0.16, 0.20, 0.25, 0.30, 0.35, and 0.42). All the samples are single phase and have grain size ~1-2 μm. As the variance σ2 increases, the paramagnetic-ferromagnetic transition shows a gradual decrease and broadening, while the decrease in insulator metal transition is sharpened. However, near equality of TC and TIM at intermediate values of σ2 could be understood in terms of the competing quenched and the grain boundary disorder. The variation in peak magnetoresistance (MR) (maximum MR around TC/TIM) with σ2 shows that maximum low field MR≈35% at H=3 kOe) 68% at H=10 kOe) is centered around σ2=0.009 857 Å2 (x=0.25). This shows that huge intrinsic MR can be obtained at relatively higher temperatures and lower magnetic fields in the region of enhanced phase fluctuations. [ABSTRACT FROM AUTHOR]

Electrospinning was used to synthsize nanofibers to be used as gas sensing materials. An electrospinning device with double nozzles of opposite polarities was designed for the synthesis of SnO2/In2O3 hetero-nanofibers in our experiments. It also included two syringes with different solutions connected to the bipolarity nozzles, and a collection plate connected to the ground. In this work, the Matrix Laboratory (MATLAB) software was used to simulate the motion locus of the bipolarity double-nozzle electrospinning process. The charged solutions were simulated as multiply charged and discretized particles. Then, force analysis was carried out for the charged particles composing the electrospun fibers, and a molecular dynamics model was built. The motion locus of the opposite electrically charged particles was calculated and simulated on the basis of the Runge-Kutta algorithm. Nanofibers with opposite polarities were attracted to and intertwined with each other and then descended to the collection plate because of gravity. The motion locus of the organic composite nanofibers synthesized using the bipolarity double-nozzle electrospinning device is shown to be identical to the simulated motion locus. [ABSTRACT FROM AUTHOR]

Hollow structured Si-Ni-C composite nanofabric was fabricated by electrospinning combined with thermal treatment. The hollow structure was obtained by calcining the precursory Si-NiO-C nanofabric under Ar atmosphere without using any sacrificial material. The resultant hollow structure could accommodate the volume effect of Si during Li-ion insertion and extraction. The NiO was reduced to Ni simultaneously with the calcination, which could increase the conductivity of the nanofabric. The hollow Si-Ni-C nanofabric formed a freestanding conductive structure which can be directly used as electrode for Li-ion batteries. The obtained self-supported anode delivered a capacity of 622 mAh/g after 100 cycles. The anode also presented a stable rate performance at 2000 mA/g. [ABSTRACT FROM AUTHOR]

Electrospinning is used to produce polyvinylidene fluoride nanofibers under various ferric chloride contents. Effect of the ferric chloride concentration on fiber diameter is investigated theoretically and experimentally. A critical value of the concentration is found, below which fiber diameter decreases with its concentration, and an opposite prediction is observed when the concentration is larger than the critical value. [ABSTRACT FROM AUTHOR]

Graphical abstract Schematic representation of the nanoparticles synthesis and functionalization process, together with a confocal microscopy image showing nanoparticle penetration in a model cell line. Highlights • Nano-emulsion templating: proper for thermosensitive compounds able to be scaled-up. • Small NPs: formation of PLGA NPs from nano-emulsions smaller than most PLGA NPs. • Versatility: CPP attachment without modifying NPs enables attachment of any peptide. • Efficient uptake: only CPP-functionalized NPs show enhanced uptake in model cells. Abstract Polymeric nanoparticles emerged a few decades ago and since then, their use and research has experienced an exponential increase, especially in the biomedical field. Among the methods to prepare polymeric nanoparticles, nano-emulsion templating is advantageous in terms of versatility, robustness, safety and efficiency. The current study represents a proof of concept of the versatility and robustness of this method for the formation of dell penetrating peptide (CPP) – functionalized PLGA nanoparticles able to efficiently cross plasma membrane and release their cargo inside the cell, where most active principles must perform their therapeutic activity. First, PLGA nano-emulsions were prepared by the phase inversion composition method, in mild conditions, required for labile pharmaceutical actives and without the need of purification steps, thus being appropriate for pharmaceutical purposes. Once nanoparticles are formed, they are functionalized, a posteriori , with a model CPP; procedure advantageous to preserve CPP functionality. It is worth noting that these nanoparticles showed smaller sizes than most PLGA nanoparticles reported previously elsewhere, property advantageous in terms of in vivo use. CPP covalent post-attachment promoted efficient nanoparticle uptake allowing them to efficiently cross plasmatic cell membranes, a bottleneck step for many nanosystems. Crossing plasmatic cell membrane was overcome with our CPP-functionalized nanoparticles, as confirmed by confocal microscopy studies. Thus, nanoparticles prepared by nano-emulsion templating can be considered a promising alternative to design novel efficient nanotherapies for multiple therapeutic purposes. [ABSTRACT FROM AUTHOR]

Abstract In this study, poly(3-hydroxybutyrate) (PHB) production from a newly isolated obligate alkaliphilic Bacillus marmarensis DSM 21297 was investigated to evaluate the ability of obligate alkaliphilic strain to produce a biopolymer. Additionally, electrospun nanofibers from B. marmarensis PHB (Bm-PHB) were generated using Bm-PHB/polycaprolactone (PCL) blend to evaluate the applicability of Bm-PHB. According to the experimental results, the metabolic activity of B. marmarensis decreased the pH of the medium by generating H+ ions to initiate Bm-PHB production, which was achieved at pH below 9.0. Regarding medium components, the addition of MgSO 4.7H 2 O and KH 2 PO 4 to the medium containing 1% glucose enhanced the amount of Bm-PHB synthesis, and an approximately 60% increase in PHB concentration was obtained in the presence of mineral salts. Based on FTIR analysis, the chemical structures of Bm-PHB and commercial PHB were found to be highly similar. Additionally, the T g and T m values of Bm-PHB were determined to be 17.77 °C and 165.17 °C, respectively. Moreover, Bm-PHB/PCL composite scaffold was generated by electrospinning method that produced nanofibers between 150 and 400 nm in diameter, with an average of 250 nm. To our knowledge, this is the first report to produce PHB from an obligate alkaliphilic Bacillus strain and PHB scaffold. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Development of AuNPs that effectivity and specifically target breast cancer cells overexpressing ERBB2. • Lower number of TZB/AuNPs improves the binding efficiency of targeted AuNPs. • Importance of material characterization and in vitro validation in the design and implementation of targeted AuNPs. Abstract The lack of understanding of fundamental nano-bio interactions, and difficulties in designing particles stable in complex biological environments are major limitations to their translation into biomedical clinical applications. Here we present a multi-parametric approach to fully characterize targeted nanoparticles, and emphasizes the significant effect that each detail in the synthetic process can have on downstream in vitro results. Through an iterative process, particles were designed, synthesized and tested for physico-chemical and bio-interactive properties which allowed the optimization of nanoparticle functionality. Taken together all interative steps demonstrate that we have synthesized a multifunctional gold nanoparticles that can detect ERBB2-positive breast cancer cells while showing stealth-like behavior toward ERBB2-negative cells and excellent physicochemical stability. [ABSTRACT FROM AUTHOR]

Abstract: Eco-friendly multifunctional denim products using environmentally sound technologies are still a challenge. In current study, enzymatic pretreatments of denim fabric using acid pectinases, laccases, and acid cellulases individually and in admixtures were carried out followed by post-nanocoating of bio-treated fabric samples with ZnO- and TiO2-NPs along with citric acid/sodium hypophosphite as ester-crosslinking/binding system using the pad-dry-microwave fixation technique. The impacts of enzymatic and subsequent nano-treatments on some physico-chemical, color change, anti-microbial and UV-blocking properties were assessed. Also, surface modification and nano-metal oxides immobilization were observed and confirmed using scan electron microscope and energy dispersive X-ray spectroscopy analysis. The experimental results revealed that the degree of surface modification and subsequent multifunctionalization are governed by type of enzyme or hybrid enzyme as well as kind of nano-metal oxide and its extent of fixation onto the modified/ester-crosslinked denim fabric structure. The synergistic effect and positive impacts of enzymatic treatment followed by nanofinishing especially in case of using ZnO-NPs on imparting better and durable performance and multifunctional properties without adversely affecting the coloration properties of denim fabric samples are confirmed and discussed. Mode of interactions was also suggested.Graphical abstract: [ABSTRACT FROM AUTHOR]

Low temperature negatively affects the engineering performance of cementitious materials and hinders the construction productivity. Previous studies have already demonstrated that TiO2 nanoparticles can accelerate cement hydration and enhance the strength development of cementitious materials at room temperature. However, the performance of cementitious materials containing TiO2 nanoparticles at low temperatures is still unknown. In this study, specimens were prepared through the replacement of cement with 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.%, and 5 wt.% TiO2 nanoparticles and cured under temperatures of 0°C, 5°C, 10°C, and 20°C for specific ages. Physical and mechanical properties of the specimens were evaluated through the setting time test, compressive strength test, flexural strength test, hydration degree test, mercury intrusion porosimetry (MIP), X-ray diffraction (XRD) analysis, thermal gravimetric analysis (TGA), and scanning electron microscopy (SEM) in order to examine the performance of cementitious materials with and without TiO2 nanoparticles at various curing temperatures. It was found that low temperature delayed the process of cement hydration while TiO2 nanoparticles had a positive effect on accelerating the cement hydration and reducing the setting time in terms of the results of the setting time test, hydration degree test, and strength test, and the specimen with the addition of 2 wt.% TiO2 nanoparticles showed the superior performance. Refined pore structure in the MIP tests, more mass loss of CH in TGA, intense peak appearance associated with the hydration products in XRD analysis, and denser microstructure in SEM demonstrated that the specimen with 2 wt.% TiO2 nanoparticles exhibited preferable physical and mechanical properties compared with that without TiO2 nanoparticles under various curing temperatures. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • We developed a method to perform fast scanning calorimetry on electrospun fibers. • Copper transmission electron microscopy (TEM) grids are used as a fiber carrier. • Poly(ethylene terephthalate) fibers were electrospun directly onto theTEM grids. • Fiber-loaded grids are cut up and placed onto the calorimeter’s chip sensor. • Quantitative thermal properties were measured for PET fibers at rate of 2000 K/s. Abstract Fast scanning chip-based calorimetry allows for the study of challenging polymers, for example, those which have rapid nucleation and crystallization kinetics, or which degrade within their melting range. Heating rates up to 4000 K/s allow for studies of hetero- and homogeneous nucleation at time scales inaccessible with conventional calorimeters, whose rates are typically less than about 0.5 K/s. Recent studies have successfully demonstrated methodologies for obtaining quantitative measurements of thermal properties of polymer samples using fast scanning calorimetry (FSC). However, these studies have been restricted to thin films or small flakes cut from bulk samples. Fibrous samples present extreme challenges due to their fluffy nature, which prevents good thermal contact for FSC. Here we present a new methodology to obtain quantitative fast scanning thermal data from electrospun nanofibers using the Mettler Flash DSC1. The technique is demonstrated using polyethylene terephthalate (PET) whose fundamental thermal properties are available in the literature, and provide a good test for the accuracy of FSC on micron- to nano-scale fibers. The structure of nanofibers requires special methods to load nanogram-sized samples onto a UFSC1 sensor. Fibers were directly spun onto copper TEM grids which provide a durable substrate to support bundles of nanofibers and possess excellent thermal conductivity allowing for a strong, repeatable signal and ensure good sample-to-sensor contact. As spun amorphous samples were held isothermally at temperatures ranging from T g (69 °C) to T m (280 °C) then heated at 2000 K/s to assess their melting behavior after cold crystallization. Results show that this sample preparation technique provides quantitative data, comparing favorably to that achieved with conventional calorimeters. [ABSTRACT FROM AUTHOR]

In recent years there is an increasing interest in the pulmonary delivery of large cohesive powder doses, i.e. drugs with a low potency such as antibiotics or drugs with a high potency that need a substantial fraction of excipient(s) such as vaccines stabilized in sugar glasses. The pulmonary delivery of high powder doses comes with unique challenges. For low potency drugs, the use of excipients should be minimized to limit the powder mass to be inhaled as much as possible. To achieve this objective the inhaler design should be adapted to the properties of the API in order to achieve a compatible combination of the drug formulation and inhaler device. The inhaler should have an appropriate powder dosing principle for which prefilled compartments seem most appropriate. The drug formulation should not only allow for accurate filling of these compartments but also enable efficient compartment emptying during inhalation. The dispersion principle must have the capacity to disperse considerable amounts of powder in a short time frame that allows the powder to reach the deep lung. Last, but not least, the inhaler should be simple and intuitive in use, be cost-effective and exhibit accurate and consistent, preferably patient independent, pulmonary delivery performance. [ABSTRACT FROM AUTHOR]

The preparation of submicron-sized particles is relevant in chemical, food and pharmaceutical applications. In pharmaceutics, spray dried submicron-sized particles (0.1–1 µm) can increase the dissolution rate as well as the solubility of poorly water-soluble drugs. Since the particle size during spray drying is mainly influenced by the droplet size, the preparation of uniform droplets smaller than 3 µm is of particular interest. In this work, a two-fluid nozzle was combined with a cyclone droplet separator. Droplets larger than the cut-off size were separated with a cyclone droplet separator and returned to the liquid feed. The aerosol at the outlet of the droplet separator was subsequently dried. The drop size of the conditioned aerosol was small, d 50 , 3 = 2  µm, and independent of the liquid-to-gas mass flow ratio and the viscosity of the liquid feed. Thus it only depended on the characteristics of the separator. Finally, the dried particles were spherical in shape and in the submicron-sized range. [ABSTRACT FROM AUTHOR]

This work aimed at designing efficient safe delivery system for intranasal (IN) brain targeting of the water soluble anti- migraine drug Almotriptan malate (ALM). Solid lipid nanoparticles (SLNs) were prepared by w/o/w double emulsion-solvent evaporation method. Selection of the optimized SLNs formula was based on evaluating particle size (PS), poly dispersity index (PDI) and entrapment efficiency (%EE). Optimized formula exhibited acceptable ranges; PS of 207.9 nm, PDI of 0.41 and %EE of 50.81%. Poloxamer 407 (Plx) at different concentrations (16%, 18%, 20% w/v), with different mucoadhesive polymers (Carbopol-974P, Na alginate, Na-CMC) were evaluated for gelling time and temperature, pH and mucoadhesion. The chosen mucoadhesive in-situ gel formula; 18% Plx 407 based-0.75%w/v Na-CMC, showed acceptable results, so that the optimized SLNs formula was further dispersed in it and evaluated for in vitro release, stability, in vivo and pharmacokinetics studies. Biomarkers’ evaluation and histopathological examination were also investigated. Results revealed rapid ALM brain delivery of the optimized formula; Brain/blood ratios at 10 min. for NF (SLNs based IN in-situ gel), ND (Free ALM IN in situ gel) and ALM i.v. (ALM IV solution) were 0.89, 0.19 and 0.31, respectively. Toxicological results confirmed the safety of NF for nasal administration. The achieved out comings are encouraging for further clinical trials of the developed system in humans in future research. [ABSTRACT FROM AUTHOR]

This study aimed to elucidate the anti-inflammatory, anti-oxidant and antifibrotic effects of gold nanoparticles (GNPs) in rats subjected to liver injury with ethanol and Methamphetamine (METH). The liver injury was induced by gavage administrations of 30% alcoholic solution (7 g/kg) once a day during 28 days, followed by METH (10 mg/kg) on the 20th and 28th days of treatment. GNPs treatment (724.96 µg/kg) during the ethanol and METH exposure was associated with reduced steatosis, hepatic cord degeneration, fibrosis and necrosis. Furthermore, there was a reduction in biochemical markers of liver damage and oxidative stress, and pro-inflammatory cytokines IL-1β and TNF-α, compared to ethanol + METH group alone. A decrease of FGF, SOD-1 and GPx-1 expression was also observed. GNPs down-regulated the activity of Kupffer cells and hepatic stellate cells affecting the profile of their pro-inflammatory cytokines, oxidative stress and fibrosis through modulation of signaling pathways AKT/PI3K and MAPK in ethanol + METH - induced liver injury in a rat model . [ABSTRACT FROM AUTHOR]

Despite the high quantities of tablets produced daily, many tableting processes are still operated at sub-optimal settings and hence lack the necessary flexibility to mitigate for possible process deviations. However, to ensure this flexibility on tableting throughput it is important to select the most robust feed frame design and settings regarding die-filling. In this research study, four paddle designs for a two-compartment forced feeder (equipped with a metering and a feeding paddle wheel) were evaluated at a wide range of process-settings (i.e. tableting speed, paddle speed, overfill level) and feed frame features (i.e. deaeration) for their impact on the die-filling step of a poorly flowing model formulation (i.e. MCC 101) using a quality-by-design approach. No benefit on die-filling was observed when using higher speeds of the metering paddle wheel compared to the feeding paddle wheel, and no convincing arguments were obtained to use the feed frame deaeration opening. Some combinations of paddle design and process-settings significantly increased the risk for inconsistent die-filling (i.e. high tablet weight variability) which can therefore limit the efficiency of the tableting process. The approach used in this study enabled to compare the paddle designs for their die-filling performance in function of varying tableting speeds, eventually resulting in the selection of a feed frame design that is most robust and therefore will provide a uniform die-filling over a wide range of throughputs. Selection of the most robust parameters is an important prerequisite for the ability of using the rotary tablet press as an agile unit-operation. [ABSTRACT FROM AUTHOR]

Formulating active pharmaceutical ingredients (APIs) in the amorphous state can increase their apparent aqueous solubility and dissolution rate and consequently improve their bioavailability. This study demonstrates, for the first time, the ability to stabilize an API in the amorphous state using a solid dispersion of magnesium carbonate nanoparticles within the API. Specifically, high proportions of ibuprofen were able to be stabilized in the amorphous state using as little as 17% wt/wt amorphous magnesium carbonate nanoparticles, and drug release rates 83 times faster than from the crystalline state were achieved. Biocompatibility of the nanoparticles was demonstrated in vitro using human dermal fibroblasts and stability of the nanocomposite formulation was verified with a storage time of six months. The success of this novel formulation provides a promising approach for achieving improved apparent solubility and enhanced bioavailability of drugs. [ABSTRACT FROM AUTHOR]

The low bioavailability of poorly water-soluble drugs is currently one of the major focuses of pharmaceutical research. One strategy currently being investigated to overcome this limitation is to decrease the particle size of the active pharmaceutical ingredients (API). An innovative process for this is spray drying with spray conditioning, which can produce submicron particles. One challenge resulting from this process is the recovery of these dispersed particles from a gas flow. Electrostatic precipitation is a common technique for air purification purposes, but an adapted electrostatic precipitator (ESP) design is necessary to achieve high collection efficiencies. The ESP design in this work uses the precipitation method of Penney filters which separates charging and collection into two stages. The ESP dimensions depend on various assumptions and simplifications. Several experiments were conducted to assess the performance of the ESP and characterize its behaviour in long-term tests. The crucial parameters in the charging process are the residence time as well as the operating voltage. These constraints were examined to enhance the collection efficiency. Based on these tests it was possible to determine a suitable charging length as well as the dimensions of the collection stage. In conclusion, an ESP customized for collecting particles in the range of 0.1–1 µm was designed, built and tested, and collection efficiencies higher than 99% were achieved for submicron particle size distributions. For a robust process continuous cleaning of the charging stage is necessary. [ABSTRACT FROM AUTHOR]

Previous data from our research group showed that chitosan-coated poly(isobutylcyanoacrylate) nanoparticles (NPs) (denoted PIBCA/Chito20) exhibited intrinsic anti- Trichomonas vaginalis activity, while PIBCA/pluronic® F68 without chitosan (PIBCA/F68) were inactive. However, the mechanism of anti- T. vaginalis activity of chitosan-coated PIBCA NPs is still unknown. Our hypothesis is that chitosan-coated NPs are internalized by the parasite, contrarily to PIBCA/F68. In this investigation, the impact of NP surface on their internalization by the protozoan was studied using flow cytometry and parasite morphological changes after different incubation times with PIBCA/Chito20 NPs were monitored by electron microscopy. Flow-cytometry revealed that PIBCA/Chito20 NPs were uptaken by T. vaginalis as early as 10-min-incubation. Drastic cell morphological transformations were observed from scanning electron microscopy and transmission electron microscopy after incubation with PIBCA/Chito20 NPs. Numerous pits were seen on cell membrane since 10 min. Gradual increase in contact time increased NP endocytosis and induced proportional damages to T. vaginalis membrane. Then, investigation of whether PIBCA/Chito20 NPs can improve MTZ anti- T. vaginalis activity was studied using checkerboard experiment. Calculation of fractional inhibitory concentration index (FICI = 3.53) showed an additive effect between NPs and MTZ. [ABSTRACT FROM AUTHOR]

The aim of this study was the development of radioactive holmium phosphate microspheres (HoPO 4 -MS) with a high holmium content and that are stable in human serum for selective internal radiation therapy (SIRT) of liver cancer. To this end, holmium acetylacetonate microspheres (HoAcAc-MS) were prepared (34.2 ± 1.0 µm in diameter, holmium content of 46.2 ± 0.8 and density of 1.7 g/cm 3 ) via an emulsification and solvent evaporation method. The concentration of HoAcAc in the organic solvent, the temperature of emulsification and the stirring speed were varied for the preparation of the HoAcAc-MS to obtain microspheres with different diameters ranging from 11 to 35 µm. Subsequently, the AcAc ligands of the HoAcAc-MS were replaced by phosphate ions by simply incubating neutron irradiated HoAcAc-MS in a phosphate buffer solution (0.116 M, pH 4.2) to yield radioactive HoPO 4 -MS. The obtained microspheres were analyzed using different techniques such as SEM-EDS, ICP-OES and HPLC. The prepared HoPO 4 -MS (29.5 ± 1.2 µm in diameter and a density of 3.1 g/cm 3 ) present an even higher holmium content (52 wt%) than the HoAcAc-MS precursor (46 wt%). Finally, the stability of the HoPO 4 -MS was tested by incubation in human serum at 37 °C which showed no visible changes of the microspheres morphology and only 0.1% of holmium release was observed during the 2 weeks period of incubation. In conclusion, this study shows that stable radioactive HoPO 4 -MS can be prepared with suitable properties to be used for cancer therapy. [ABSTRACT FROM AUTHOR]

Dendrimers are novel polymeric nanoarchitectures characterized by hyper-branched 3D-structure having multiple functional groups on the surface that increases their functionality and make them versatile and biocompatible. Their unique properties like nanoscale uniform size, high degree of branching, polyvalency, water solubility, available internal cavities and convenient synthesis approaches make them promising agent for biological and drug delivery applications. Dendrimers have received an enormous attention from researchers among various nanomaterials. Dendrimers can be used as a carrier for diverse therapeutic agents. They can be used for reducing drug toxicities and enhancement of their efficacies. The present review provide a comprehensive outline of synthesis of dendrimers, interaction of dendrimer with guest molecules, properties, characterization and their potential applications in pharmaceutical and biomedical field. [ABSTRACT FROM AUTHOR]

Essential oils are recognized as valuable active pharmaceutical ingredients attributed to a set of biological properties, which include antibacterial, antifungal, antiviral, antioxidant, anticancer, immune-modulatory, analgesic and anti-inflammatory activities. Their use in pharmaceutics is however compromised by their limited water solubility and low physicochemical stability (i.e. volatility, oxidation). In order to overcome these limitations, we aimed to develop nanostructured lipid carriers (NLC) as delivery systems for Mediterranean essential oils, in particular Rosmarinus officinalis L., Lavandula x intermedia “Sumian”, Origanum vulgare subsp. hirtum and Thymus capitatus essential oils, selected on the basis of their antioxidant and anti-inflammatory activities. NLC composed of Softisan (as solid lipid) have been produced by phase inversion temperature (PIT) and high-pressure homogenization (HPH), using two different emulsifiers systems. Particles have been further characterized for their mean particle size, polydispersity, zeta potential, morphology and chemical interactions. Best NLC formulations were obtained with Kolliphor/Labrafil as surfactants, and using Rosmarinus , Lavandula and Origanum as essential oils (PDI between 0.126 and 0.141, Zave < 200 nm). Accelerated stability studies have also been carried out to estimate the effect of the production method and surfactant composition on the long-term stability of EOs-loaded NLC. In vitro biological cell viability and anti-inflammatory activities were evaluated in Raw 264.7 cells (macrophage cell line), while in vitro antioxidant activity was checked by DPPH assay. Lavandula and Rosmarinus NLC were shown to be the most biocompatible formulations up to a concentration of 0.1% (v/v), whereas they were able to induce a dose-dependent anti-inflammatory activity in the order Lavandula  >  Rosmarinus  ≥  Origanum . [ABSTRACT FROM AUTHOR]

Phospholipid nanoparticles (PNs) encapsulating vitamin C and E derivatives, 3-O-cetyl ascorbic acid (CA) and tocopherol acetate (TA), respectively, were examined using the film rehydration and extrusion method. PN formulations (TA-Cassome) were prepared by mixing CA, soya phosphatidylcholine (Soya PC), sodium cholate, and TA at a molar ratio of 20/80/5/6. Glycerol (GL) or diglycerol (DG) were also added to improve the skin accumulation of CA and TA. Three TA-Cassome formulations were evaluated using a dynamic light scattering (DLS), NMR, TEM, skin accumulation test for CA and TA, and small-angle X-ray diffraction (SAXD) analysis. TA-Cassome formulations (150 nm) were stable for two weeks and they encapsulated 1.8 mg/mL of TA. TEM and SAXD analysis revealed that the nanoparticles formed a spherical multilayer structure. 1 H and 31 P NMR indicated that GL and DG enhanced the proton mobility of choline groups of soya PC molecules located on the membrane surface of TA-Cassome. Accumulation of CA and TA in the dermis was increased by adding GL and DG. SAXD analysis revealed that GL and DG promoted the formation of new lamellar structures on the stratum corneum, which contributed to improving the skin accumulation of CA and TA. [ABSTRACT FROM AUTHOR]

A new class of non-spherical particles was recently designed in our research group by mixing a polysaccharide grafted with fatty acids and α-cyclodextrin in water. Because their flat surfaces, and according to their size, particles are called micro- or nano-platelets. Here, we varied the composition of fatty acids grafted on chitosan (oleic acid, palmitic acid or stearic acid) and characterized platelet morphology. Transmission electron microscopy (TEM), cryogenic TEM, scanning electron microscopy, atomic force microscopy (AFM) and confocal laser scanning microscopy experiments showed that the platelets have a preferentially hexagonal shape with sharp edges, independently on alkyl chain grafted on chitosan. Furthermore, AFM topographic analysis of platelet surface showed parallel thin terraces with 12–14-nm height, suggesting a multi-layered structure alternating chitosan and fatty-acid/α-cyclodextrin inclusion complexes. We also revealed for the first time that a simple magnetic mixing of fatty acids with α-cyclodextrin in water results from solid inclusion complexes with a crystalline structural organization characterized by powder X-ray diffraction. Our results demonstrate that fatty acid/α-cyclodextrin interaction is the driving force for platelet formation. [ABSTRACT FROM AUTHOR]

Oxytocin is a promising candidate for the treatment of social-deficit disorders such as Autism Spectrum Disorder, but oxytocin cannot readily pass the blood-brain barrier. Moreover, oxytocin requires frequent dosing as it is rapidly metabolized in blood. We fabricated four polymeric nanoparticle formulations using poly(lactic-co-glycolic acid) (PLGA) or bovine serum albumin (BSA) as the base material. In order to target them to the brain, we then conjugated the materials to either transferrin or rabies virus glycoprotein (RVG) as targeting ligands. The formulations were characterized in vitro for size, zeta potential, encapsulation efficiency, and release profiles. All formulations showed slightly negative charges and sizes ranging from 100 to 278 nm in diameter, with RVG-conjugated BSA nanoparticles exhibiting the smallest sizes. No formulation was found to be immunogenic or cytotoxic. The encapsulation efficiency was ≥75% for all nanoparticle formulations. Release studies demonstrated that BSA nanoparticle formulation exhibited a faster initial burst of release compared to PLGA particles, in addition to later sustained release. This initial burst release would be favorable for clinical dosing as therapeutic effects could be quickly established, especially in combination with additional sustained release to maintain the therapeutic effects. Our size and release profile data indicate that RVG-conjugated BSA nanoparticles are the most favorable formulation for brain delivery of oxytocin. [ABSTRACT FROM AUTHOR]

Lipid polymer hybrid nanoparticles (LPHNs) combine the characteristics and beneficial properties of both polymeric nanoparticles and liposomes. The objective of this study was to design and optimize gemcitabine hydrochloride loaded LPHNs based on the central composite design approach. PLGA 50:50/PLGA 65:35 mass ratio (w/w), soya phosphatidylcholine (SPC)/polymer mass ratio (%, w/w) and amount of DSPE-PEG were chosen as the investigated independent variables. The LPHNs were prepared with modified double emulsion solvent evaporation method and characterized by testing their particle size, encapsulation efficiency, and cumulative release. The composition of optimal formulation was determined as 1,5 (w/w) PLGA 50:50/PLGA 65:35 mass ratio, 30% (w/w) SPC/polymer mass ratio and 15 mg DSPE-PEG. The results showed that the optimal formulation gemcitabine hydrochloride loaded LPHNs had encapsulation efficiency of 45,2%, particle size of 237 nm and cumulative release of 62,3% at the end of 24 h. The morphology of LPHNs was found to be spherical by transmission electron microscopy (TEM) observation. Stability studies showed that LPHNs were physically stable until 12 months at 4 °C and 9 months at 25 °C/60% RH. The results suggest that the LPHNs can be an effective drug delivery system for hydrophilic active pharmaceutical ingredient. [ABSTRACT FROM AUTHOR]

The aim of this study was to elucidate the optimized fabrication factors influencing the formation and properties of shellac (SHL) nanofibers loaded with an antimicrobial monolaurin (ML). The main and interaction effects of formulation and process parameters including SHL content (35%-40% w/w), ML content (1%-3% w/w), applied voltage (9-27 kV) and flow rate (0.4-1.2 ml/h) on the characteristic of nanofibers were investigated through a total of 19 experiments based on a full factorial design with three replicated center points. As a result, the SHL content was the major parameter affecting fiber diameter. Another response result revealed that the SHL content would be also the most significant negative impact on amount of beads. An increase in the concentration of SHL leaded to a reduction in the amount of beads. From the results of characterization study, it was proved that ML might be entrapped between the chains of SHL during the electrospinning process exhibiting an excellent encapsulation. According to the response surface area, small (∼488 nm) and beadless (∼0.48) fibers were obtained with the SHL and ML contents of 37.5% and 1.1% w/w respectively, at the applied voltage of 18 kV and the flow rate of 0.8 ml/h. In addition, the results of the kill-kinetic studies showed that SHL nanofibers loaded with ML exhibited an excellent antibacterial activity against Staphylococcus aureus, while Escherichia coli was less affected due to the hydrophilic structure of the its outer membrane. ML also exerted an antifun-gal activity by reducing the number of Candida albicans colonies. Based on their structural and antimicrobial properties, SHL nanofibers containing ML could be potentially used as a medicated dressing for wound treatment. [ABSTRACT FROM AUTHOR]

In this study, we developed a polymeric nanofiber patch (PNP) for topical disease treatment using electrohydrodynamic atomization (EHDA). The nanofibers were prepared using various concentrations of polyvinyl alcohol (PVA) and tamarind seed gum and loaded with clindamycin HCl as a model drug. The precursor polymer solutions were sprayed using the EHDA technique; the EHDA processing parameters were optimized to obtain blank and drug-loaded PNPs. The skin adherence, translucence, and ventilation properties of the prepared PNPs indicated that they are appropriate for topical application. The conductivity of the polymer solution increased with increasing PVA and clindamycin concentrations, and increasing the PVA concentration enhanced the solution viscosity. Based on scanning electron microscopy analysis, the PVA concentration had a pronounced effect on the morphology of the sprayed product. Nanofibers were fabricated successfully when the solution PVA concentration was 10%, 13%, or 15% (w/v). The applied voltage significantly affected the diameters of the prepared nanofibers, and the minimum nanofiber diameter was 163.86 nm. Differential scanning calorimetry and X-ray diffraction analyses indicated that the modeldrug was dispersed in PVA in an amorphous form. The PNP prepared with a PVA:gum ratio of 9:1 absorbed water better than the PVA-only PNP and the PNP with a PVA:gum ratio of 9.5:0.5. Moreover, the PNPs loaded with clindamycin at concentrations of 1%-3% prohibited the growth of Staphylococcus aureus more effectively than clindamycin gel, a commercially available product. [ABSTRACT FROM AUTHOR]

In this study, a simple, general and straightforward method for growing metal-organic frameworks (MOFs) crystals directly on nanofibers is presented. A chelating polymer was first blent with metal cation and then electrospun. The obtained nanofibers were immersed in a linker solution. Metal cations were released and the metal-organic frameworks crystals were grown on the fibers' surface. In this work, this method was tested with polyvinyl alcohol as chelating polymer, Zn2+ as metal cation and Terephthalic acid as linker. The pair cation/linker corresponds to the MOF-5. The latter is a robust metal organic framework formed from Zn4O nodes with 1,4-benzodicarboxylic acid struts between the nodes. SEM images revealed that the MOF-5 nanocrystals have grown along the PVA/Zn2+ nanofibers that served as the crystals' growth template by providing the Zn2+ ions. This result was also confirmed by infrared spectroscopy, which indicates the presence of characteristic bands of MOF-5 in the modified nanofibers spectrum. Moreover, the X-ray diffraction showed that MOF-5 material was well crystallized on the nanofibers surface according to a cubic symmetry with a space group Fm-3m and a lattice constant a = 25.8849 Å. [ABSTRACT FROM AUTHOR]

ABSTRACT: Non‐isocyanate polyurethanes (NIPU) have rapidly emerged as a sustainable, less toxic, and environmentally friendly alternative to traditional isocyanate‐based thermoplastic polyurethane (TPU) synthesis. TPU is widely used in the medical industry due to its excellent mechanical properties and elasticity. However, little work has been done to synthesize and electrospin NIPU into fibrous mats for biomedical applications. In this work, melt polymerization of a plant oil‐based cyclic carbonate monomer with polyether soft segments and various diamines yielded isocyanate‐free, segmented poly(amide hydroxyurethane)s (PAHUs). Electrospinning of segmented PAHUs afforded ductile, free‐standing fibrous mats with Young's modulus values between 7 and 8 MPa, suitable for tissue scaffold applications. PAHU fiber mats exhibited 3–4 times greater water uptake than the electrospun TPU control, demonstrating potential utility in drug delivery. Fibroblasts adhered to electrospun PAHU fibrous mats with viability values over 90% after 72‐h, validating its biocompatibility. The results highlight the high performance and potential of electrospun isocyanate‐free polyurethanes mats for biomedical application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46464. [ABSTRACT FROM AUTHOR]

An interesting architecture of robust, highly reproducible, template-free synthesis of phase pure carbon-incorporated short ZnO nanotubes through polymer assisted sol-gel method is presented here. These nanotubes exhibit enormous surface oxygen vacancies and mid bandgap levels confirmed by X-ray photoelectron spectroscopy. These carbon-modified nanotubes exhibit encouraging results in photocatalytic studies, as there is a 16% greater degradation of contaminant dye than in the pristine ZnO nanotube. The reactive oxygen species generated from the photocatalysts were experimentally confirmed and quantified. Super hydrophilic nature renders these nanotubes suitable for antifogging application as observed from contact angle measurements. Characterisation and mechanism of a competent material with improved photoresponse, promising greater energy efficiency and anti-fog have been described in this investigation. [ABSTRACT FROM AUTHOR]