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Graphene-based functional coatings for cotton textiles were realized through an easy dip-coating procedure. Cotton fabrics were coated with a reduced graphene oxide (rGO) layer and then protected with a very thin polyurethane (PU) layer that does not affect the flexibility and the hand of the pristine cotton. The application of the rGO coating induces electrical conductivity to the fabric and the application of the PU phase increases the durability of the coatings, that show very stable surface resistivity after 10 washing cycles performed at temperatures up to 40 °C. Furthermore, the rGO and rGO/PU coated fabrics show good comfort properties, increased thermal conductivity and breathability with respect to cotton. In particular, the realized coatings allow to confine the heat transfer in correspondence of a localized heating source, which is very interesting for thermal therapy applications. Finally, the rGO/PU coated fabrics present a piezoresistive behaviour characterized by very stable electrical response to applied stretching up to 50% deformation, high sensitivity especially at low deformations with gauge factor values up to 11.7 and fast response time down to 500 ms when stretched at 100 mm/min rate at 2.5% strain. Overall, the results demonstrate that rGO/PU coated fabrics are very promising wash-durable electrically conductive e-textiles with improved comfort, enhanced thermal conductivity for possible thermal therapy applications, and piezoresistive properties for sensing applications as human motion monitoring.

The manuscript details the first literature example of fibers of poly( l -lactic acid) (PLLA) containing a mosquito repellent agent, N,N-diethyl-3-methylbenzamide (DEET). The fibers were prepared by electrospinning, are defect-free and have uniform diameter of the order of magnitude of 1 µm. Thermogravimetry and infrared spectroscopy showed that it is possible to incorporate more than 50 wt% of DEET, which is then slowly released to the environment. As such, the fibers can function as a drug delivery device. Further structural analyses disclosed that PLLA in DEET-containing fibers is semicrystalline, and contains α-crystals formed during electrospinning. Thermal, morphological and structural characterization revealed that the PLLA/DEET electrospun fibers have potential as novel material for controlled release of DEET, which, coupled with the ease of fabrication, detailed here, can provide innovative tools for fighting mosquito-caused diseases.

La Notte dei Ricercatori è una manifestazione annuale promossa sin dal 2005 dalla Commissione Europea. Con uno stanziamento di oltre 15 milioni di euro, si svolge simultaneamente in 29 Paesi europei l'ultimo weekend del mese di settembre ed è animata da 3 scopi precisi: promuovere l'eccellenza, sensibilizzare sulla ricerca, aumentare l'interesse per le carriere scientifiche. Il lavoro descrive il contributo dello IPCB alla Notte dei Ricercatori 2021

Il Festival della scienza è un evento tematico annuale che si tiene annualmente tra la fine di ottobre e l'inizio di novembre a Genova dal 2003. Ogni anno il programma presenta mostre, laboratori, percorsi didattici interattivi, esibizioni fotografiche e artistiche, conferenze, tavole rotonde, workshop, spettacoli teatrali, performance musicali e proiezioni cinematografiche vengono organizzati in tutta la città di Genova durante il festival. Il lavoro descrive il contributo dello IPCB alla "Festa della Scienza di Genova 2021"

Spray drying unit operation is generally used for separating and drying a solid that cannot be mechanically dried because cannot be exposed to high-temperature atmospheres for long periods. For this reason, spray dryers are related to heat-sensitive products like food or drugs but can be also used for natural extract encapsulation in order to increase their thermal stability. In this work, this last aspect was investigated and a model of co-current spray-drying, was developed and validated. This model is based on mass, energy and momentum balances and take into account of the distribution of the particle size. An experimental campaign was performed using a laboratory scale spray dryer (Buchi Mini Spray Dryer B-290, Switzerland) to validate the model. Maltodextrin and cyclodextrin were used as carrier to encapsulate grape skin and citrus extracts respectively. Different tests were done varying the operating condition of the spray dryer like the inlet air temperature (from 120°C to 180°C) and the mass ratio between carrier and natural extract. Simulation results and experimental data showed a good agreement in terms of mass yield and outlet temperature, while the outlet moisture content show slightly difference e needs to be further investigated.

Electrospinning is strongly attractive for the fabrication of fibrous platforms for a wide range of applications like electronic devices, electroactive wearables and wound healing scaffolds. Recently, this versatile, reliable and low-cost technique has been investigated with a wide selection of active materials to fabricate nonwoven meshes to be used as smart filters to control the adsorption/delivery of small molecules. In this work, electrospinning is proposed for the fabrication of polyvinylidene fluoride (PVDF)-based fibers able to control the adsorption of negatively charged molecules such as Methylene Blue (MB). It is demonstrated that PVDF fibers with pronounced surface roughness - from 126 nm to 1983 nm - are able to adsorb a higher amount of MB than smooth fibers made of PCL, used as a control. Moreover, the integration of a p-type conjugated polymer such as Poly (3-hexylthiophene) (P3HT), concurs influencing the adsorption mechanism of MB, mediated by the microscopic interactions among dipolar beta phases in PVDF. In addition, an increase of MB absorption was measured in the presence of an externally applied voltage (10 kV), ascribable to the P3HT oxidation change that influences microscopic dipole interactions. Hence, we suggest the use of P3HT/Polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) fibers to design new filtering systems able to tune the absorption of negatively charged molecules for environmental and biomedical applications. (C) 2020 Elsevier B.V. All rights reserved.

Within the framework of neurodegenerative disorder therapies, the fabrication of 3D eumelanin architectures represents a novel strategy to realize tissue-engineering scaffolds for neuronal cell growth and control by providing both mechanical support and biological signals. Here, an appropriate procedure combining electrospinning, spin coating and solid-state polymerization process is established to realize the scaffolds. For biological analysis, a human derived cell line SH-SY5Y from neuroblastoma is used. Cell maturation on eumelanin microfibers, random and aligned, is evaluated by using confocal analysis and specific markers of differentiating neurons (beta III tubulin and GAP-43 expression). Cell morphology is tested by SEM analysis and immunofluorescence techniques. As results, eumelanin coated microfibers prove capable to support biological response in terms of cell survival, adhesion and spreading and to promote cell differentiation toward a more mature neuronal phenotype as confirmed by GAP-43 expression over the culture.

Herein, engineered electrospun core/shell nanofibers containing different percents of Artemisinin (ART) were developed as new systems for drug administration in malaria and prostate cancer fields. In order to preserve drug bioavailability, a hyperbranched poly(butylene adipate) (HB), acting as crystal suppressant of ART, was employed as core material. Poly(vinylpirrolidone) (PVP) was selected as shell material being easy processable, self-standing and effective in facilitating ART release in aqueous medium. The investigation was carried out considering both the technological and biological aspects, by first assessing the release capability of nanofibers, and successively by evaluating the pharmacological activity of encapsulated ART against cancer cell proliferation and malarial parasites ( P. falciparum ) growth through in vitro tests. Inferred results confirmed the formation of nanofibers with an effective drug-loaded capability. Moreover, the different hydrophobic character of the HB and PVP enabled the triggering of the drug release and the control on its solubility in the aqueous medium.

Serat nano kitosan telah berhasil dibuat dengan penambahan polietilen oksida (PEO) sebagai polimer sekunder pada kondisi larutan dan parameter proses pemintalan elektrik yang optimum. Pada penelitian ini, larutan polimer kitosan/PEO pada berbagai konsentrasi (3,2, 3,6, dan 4 wt%) dan rasio (3:2 dan 1:1) dipintal secara elektrik ( electrospinning ) untuk memperoleh serat dengan morfologi paling baik. Selain kondisi larutan, parameter proses pintal elektrik yang penting seperti tegangan, laju alir umpan, dan jarak antara jarum dengan kolektor juga disesuaikan untuk mendapatkan proses dengan kondisi jet polimer yang stabil. Serat nano yang terbaik yakni tanpa butiran polimer ( polymer microspheres ) dan minim jumlah manik-manik ( beads) berhasil diperoleh pada konsentrasi kitosan/PEO 4 wt% dan rasio 3:2. Parameter proses yang digunakan untuk mendapatkan serat ini yaitu tegangan 30 kV, laju alir umpan 0,3 ml/jam, dan jarak antara jarum dan kolektor 30 cm. Karakterisasi morfologi serat dari setiap eksperimen dilakukan dengan menggunakan mikroskop Phenom. Selanjutnya, serat nano terbaik yang diperoleh dikarakterisasi dengan menggunakan SEM dan diameter rata-rata serat diukur dengan aplikasi ImageJ. Hasil menunjukkan bahwa serat nano yang dihasilkan pada kondisi optimum memiliki diameter rata-rata 68 nm dan distribusi ukuran diameter serat tersebar cukup lebar mulai dari 30-150 nm.

Nanobioscience is the research area that focuses on small materials from submicrometric to nanometric scale able to interact with tissues at the molecular level with high degree of functional specificity and control. A large group of nanomaterials including nanotubes, nanofibers, liposomes, nanoparticles, polymeric micelles, and nanogels are currently investigating for this scope. Such materials can be manipulated to influence specific activities of biological systems at a molecular or even supramolecular level and responding to the cell environment also minimizing undesired side effects. Hence, promising strategies based on the use of nanotubes and/or nanofibers are emerging to trigger specific cell events in vitro and in vivo for the treatment of damaged or cancerous tissues. Nanotubes and nanofibers can be produced from various materials, such as carbon, synthetic polymers, biological macromolecules (i.e., DNA, proteins, and lipids), silicon, and glasses, case by case, through the implementation “ad hoc” of different process technologies. As a function of their peculiar composition and chemistry, they may be biodegradable or biostable with different response in the host tissue, thus playing a different role in the interface of cells with scaffolds or extracellular tissue analogues. In this chapter, we provide an overview of current studies based on the use of nanotubes and/or nanofibers in tissue repair and regeneration, by emphasizing the influence of processes and their parameters onto the ultimate properties of nanoscale systems for an effective validation in vitro and in vivo.

In this manuscript we present preliminary data on nanofibers containing N,N-diethyl-3-methylbenzamide (DEET), the active ingredient used in many commercial insect repellents. To our knowledge, this is the first time that such materials have been prepared by electrospinning, the only available literature data are related deal with miscibility and thermal properties of DEET/PLLA blends. In our study DEET was incorporated into PLLA-chloroform solutions that were successfully electrospun into mats. Spun mats were characterized by thermogravimetry to determine the exact amount of DEET encapsulated into the fibrous PLLA matrix, and by scanning electron microscopy to evaluate DEET effect on fibers morphology.

The footwear market is addressing eco-sustainable solutions to the continuous demand for materials that at the same time show lighter weight with higher comfort. Toward this aim, a biodegradable matrix, poly(vinyl alcohol) (PVA), was used to obtain foams through an eco-sustainable methodology based on high speed mixing, without the use of chemical blowing agents. Moreover, considering that good thermoregulating performance in terms of heat transfer and perspiration is required for good quality shoes, microencapsulated phase change materials (PCMs) were incorporated into PVA foams. Foam morphologies investigated by SEM reveal that PCMs are finely dispersed through the PVA matrix. Mechanical properties of foams were analyzed in terms of compression behavior and shape memory recovery, triggering the dimensional changes by both temperature and relative humidity. The thermoregulating properties confirm that the presence of microcapsules affects the heat transfer phenomenon, since part of the heat provided by the source is involved in the wax phase transition.

The fabrication of water soluble nanofibres based on proteins from vegetable source currently represents an emerging strategy to massively release active principles via rapid degradation in targeted sites. In this work, propolis loaded nanofibres made of zein, were fabricated via electrospinning. The gradual increase of propolis content promotes a reduction of fibre diameters from 425 +/- 212 to 116 +/- 83 due to non-covalent interactions between carboxyl groups of phenolic compounds and protein amide groups as confirmed by FTIR spectra. Accordingly, in vitro degradation studies via UV spectra also proved that selected compounds such as diferuloylputrescine (DFP) can be more slowly released-after 48 h-in the presence of propolis. This enable to design nanofibrous devices really promising to face inflammatory diseases due to the presence of lesions in the oral cavity.

Electrospinning is a versatile technology for the production of polymer micro/nanoscale fibers. It provides the direct addition of bioactive payloads into micro/nanofibers thus improving the encapsulation efficiency and reducing the burst release via proper selection of drug-polymer-solvent system or electrospinning setup. In addition, since electrospun fibers have one dimension at the microscopic scale but another dimension at the macroscopic one, it is possible to combine the advantages possessed by functional materials on the nanometer scale. A large surface to volume ratio, with the properties of conventional solid membranes, such as ease of manipulation and applicability in any size and shape, making them suitable for biomedical or healthcare applications both topically (i.e. skin) and locally (i.e. tumor). This communication deals with electrospun fibrous systems containing active compounds extracts from plants such as Artemisinin and Propolis; these systems have been properly realized to preserve the pharmacological activity of drugs and evaluated as potential delivery systems for vector-born deseases and cancer, reducing the damage to non-target organism and environment.

Eumelanins, the black insoluble pigments of human skin, eyes and substantia nigra (neuromelanin), stand today as a unique source of inspiration for the design and implementation of soft biocompatible multifunctional materials for bio-optoelectronic devices. Interest in eumelanins stems from bioavailability, biocompatibility and a peculiar set of physicochemical properties, i.e. broadband absorption in the UV-visible range, intrinsic free radical character, water-dependent hybrid ionic-electronic conductor behaviour, supporting optimistic feelings about a possible rise of eumelanin-mimics as innovative bioinspired solutions for organic bioelectronics. However, a number of conceptual and technological gaps still hinder a rapid progress of melanin-based organic electronics and bioelectronics, including in particular the limited contribution of electronic conductivity and current decay with time under biasing. Herein, we provide a concise overview of the structural and optoelectronic properties of melanins with a view to bringing to focus main issues and challenges en route to bioelectronic applications. Copyright © Materials Research Society 2015.

The effects induced by ball milling treatment on PVC features and properties were deeply investigated through a multitechnique approach. SEM analysis showed a drastic change in PVC morphology; the hierarchical structure of PVC grains was partially destroyed as well as the domain size strongly reduced. A X-ray diffraction and DSC comparative study proved a structural modification in the PVC crystalline phase. Moreover, it was found that these morphological and structural changes strongly affected the gelation behavior, the microstructure and the mechanical parameters of PVC. In particular, the gelation time increased with increasing the ball milling time; the residual primary crystallite content doubled with respect to neat PVC and the toughness improved up to 25% as a function of the resulting microstructure. © 2011 Elsevier B.V. All rights reserved.

Eumelanin integration in silica aerogel (SA) was achieved via supercritical adsorption of 5,6-dyhydroxyindole (DHI) from CO2. Notably, after the supercritical treatment, DHI evolved towards spontaneous polymerization, which resulted in uniform pigment development over the SA. The new material was characterized for its morphological and physicochemical properties, disclosing the formation of a eumelanin-like coating, as confirmed by UV&ndash, vis and electron paramagnetic resonance (EPR) spectroscopy.

This work is focused on the realization of biodegradable poly(vinyl alcohol) (PVOH) based foams through an eco-friendly methodology for applications into the footwear market. Considering that good thermo-regulating performance in terms of heat transfer and perspiration are required for good quality shoes, microencapsulated phase change materials (MPCMs) were incorporated into PVOH foams. Microstructure, thermal and mechanical properties as well as the effect of temperature and relative humidity on mechanical properties were analyzed . The thermo-regulating properties of samples were studied using a self-designed prototype equipment composed of a Peltier-effect device coupled with an infrared thermo-camera.

Poly(vinyl chloride) (PVC)-based nanocomposites containing calcium carbonate nanoparticles (CaCO3) were prepared. Different nanoparticle surface modifiers were selected and tested to promote matrix/filler interactions and, consequently, to obtain high- performance materials. In particular, the nanoparticles were modified with poly(acrylic acid) (PAA) and poly (butadiene-co-acrylonitrile-co-acrylic acid) (PBAA). For comparison, PVC-based materials, with the addition of commercial neat and stearic acid modified CaCO3, were also prepared. The influence of CaCO3 and surface modifiers on the gelation, thermal properties, thermal stability, and mechanical properties of PVC was studied. The gelation time of the rigid PVC/CaCO3 composites decreased as a function of the percentage and surface treatment of CaCO3. Morphological analysis proved the effectiveness of PAA and PBAA as surface modifiers; they obtained for the corresponding materials a typical nanostructured morphology. A significant improvement in the PVC thermal stability was recorded with the addition of neat and stearic acid modified CaCO3. Finally, mechanical tests showed an increase in the flexural strength and toughness of PVC as a function of the nanoparticle surface modifier. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The influence of nanosized calcium carbonate on the gelation process, thermal stability and mechanical properties of rigid poly(vinyl chloride) has been studied. The gelation time of rigid PVC/calcium carbonate nanocomposites depends on the percentage and superficial treatment of CaCO3. The results of thermogravimetric analysis underline an improvement of the thermal stability as a function of the surface modifier. Finally, the flexural modulus, the flexural strength as well as the critical stress intensity factor increase with the addition of poly(acrylic acid) (PAA) or poly(butadiene-co- acrilonitrile-co-acrylic acid) (PBAA) coated nanoparticles.

Dynamic thermogravimetric analysis under nitrogen flow was used to investigate the thermal decomposition process of high-density poly(ethylene) (HDPE)-based composites reinforced with cellulose fibers obtained from the recycling of multilayer carton scraps, as a function of the cellulose content and the compatibilization. The Friedman, Flynn–Wall–Ozawa, and Coats–Redfern methods were used to determine the apparent activation energy (E a) of the thermal degradation of the cellulose component into the composites. E a has been found dependent on the cellulose amount and on the cellulose/polymer matrix interfacial adhesion. In particular, it has been evidenced an increase of the cellulose thermal stability as a consequence of the improved interfacial adhesion between the components in NFR composites.

In this article, an alternative mechanical recycling of multilayer carton scraps (MC), consisting in the use of MC without the physical separation of its different fractions (cellulose fibers and low-density polyethylene, 80/20 wt/wt), is proposed. In particular, MC was considered as a source of cellulose fibers in the obtainment of high-density polyethylene (HDPE)-based composites. Composites containing up to 60 wt % of milled MC were prepared by reactive processing, i.e., by adding different amount (5 and 10 wt %) of a linear low-density polyethylene grafted with maleic anhydride (coupling agent, maleated linear low-density polyethylene) during HDPE/MC mixing. Then, structure/properties relationships were deeply investigated as a function of MC and coupling agent content. The coupling agent was able to induce a complete polymeric covering of cellulose fraction as well as a strong HDPE/cellulose interfacial adhesion. As a consequence, a significant improvement of mechanical properties at low and high deformation rates as well as a very interesting response of composites to water vapor permeability was obtained. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

This research reports the feasibility of use of rubber tire waste as a component material in textile reinforced concrete. Study mainly focus on arriving at a strengthening system for RC beams using textile reinforced concrete. Basalt and alkali resistant glass textiles are used as reinforcement and ground rubber tire powder incorporated cementitious mortar is used as binder. Experimental investigations are carried out to arrive at the mechanical properties of different percentages of rubber tire powder in a cementitious mortar. Three types of mixes with different rubber contents ranging from 2.5% to 7.5% of partial replacement of cement are used in the concrete mix. Mechanical characterization studies are performed to determine the compressive strength and split tensile strength. The micro structural evaluation is carried by using scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDAX) to correlate the micro structural behaviour with mechanical properties. Further, behaviour of reinforced concrete beams strengthened with ground rubber tire (GRT) powder incorporated textile reinforced concrete is studied in detail. The encouraging results obtained in present study will pave way for extending the application potential of ground rubber tire as an ingredient in textile reinforced concrete for many structural applications in an environmental friendly and cost-effective way.