76 research outputs found

    Nano galaxy

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    Unconventional nanomanufacturing on a substrate

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    Nanostructured materials may be defined as those materials whose structural elements (clusters, crystallites or molecules) have dimensions in the 1- to 100-nm range. The explosion in both academic and industrial interest in these materials over the past decade arises from the remarkable variations in fundamental electrical, optical and magnetic properties that occur as one progresses from an ‘infinitely extended’ solid to a particle of material consisting of a countable number of atoms. Nanoscience and nanotechnology cover many different areas, but one key set of methods for both concerns nanofabrication. There is a growing interest specifically in manufacturing methods allowing more efficient processes, minimising energy usage/cost and simplifying up-scaling requirements. In the framework of this thesis some novel processes of nanomanufacturing are established that are based on self-organization, with and without templates to from a large scale of 1D-horizontal nanostructures like wires and rings directly onto a substrate in a simple and cost-effective manner. The examination of these processes deals with the identification and control of the relevant growth and ordering parameters. This examination is done during the formation of ordered structures as well as after the growth process, so that the formed structures do not get distorted. The new paradigm for producing lateral nanostructures directly on a substrate is realized using unconventional approaches: A)Fracture Approach, shows a novel templated self-organization approach where thin film fracture is employed as a mould for guiding the self-organization of sputtered material to form nanowires. B)Drop Approach, concerns an unconventional template-less self-organization approach using a drop on hot plate. The building block is utilized by direct chemistry on the surface (localized chemistry) and the patterning is stimulated by external force like capillary and/or hydrodynamic instability

    An amphiphilic, graphitic buckypaper capturing enzyme biomolecules from water

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    The development of carbon nanomaterials for adsorption based removal of organic pollutants from water is a progressive research subject. In this regard, carbon nanomaterials with bifunctionality towards polar and non-polar or even amphiphilic undesired materials are indeed attractive for further study and implementation. Here, we created carbon buckypaper adsorbents comprising amphiphilic (oxygenated amorphous carbon (a-COx)/graphite (G)) nanofilaments that can dynamically adsorb organic biomolecules (i.e., urease enzyme) and thus purify the wastewaters of relevant industries. Given the dynamic conditions of the test, the adsorbent was highly efficient in adsorption of the enzyme (88%) while being permeable to water (4750 L·h-1m-2bar-1); thus, it holds great promise for further development and upscaling. A subsequent citric acid functionalization declined selectivity of the membrane to urease, implying that the biomolecules adsorb mostly via graphitic domains rather than oxidized, polar amorphous carbon ones.Peer reviewe

    Antiviral polysaccharide and antiviral peptide delivering nanomaterials for prevention and treatment of SARS-CoV-2 caused COVID-19 and other viral diseases

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    Publisher Copyright: © 2023 The AuthorsAntiviral peptides and antiviral polysaccharides can play a major role in the prevention and treatment of emerging viral health problems. These antiviral compounds are biocompatible, environmentally friendly, non-toxic, and cost-effective, yet are poorly water soluble and vulnerable to enzymatic (protease) degradation within the aggressive intercellular microenvironment. Therefore, they should be properly protected and delivered to viruses and host cells by the well-designed nanocarriers that mimic viruses in terms of size, morphology, and smart function. This literature review is meant to introduce the latest advances (mainly within the past five years) in antiviral nano-assemblies comprising antiviral peptides or antiviral polysaccharides. To the best of our knowledge, there is no similar study in the literature that has solely and sufficiently investigated such antiviral nanomaterials partially or totally derived from nature. The rational classification of microorganism-, plant-, and animal-derived antiviral polysaccharide and antiviral peptide delivering nanomaterials and exploration of their relevant applications will clarify the promising capacity of these state-of-the-art materials for a number of technologies developed to inactivate viruses.Peer reviewe

    Reflective Coloration from Structural Plasmonic to Disordered Polarizonic

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    The generation of pigment‐free colors by nanostructures and subwavelength patterns has evolved in the last decade and outperformed the conventional paints in terms of durability, recyclability, and environmental friendliness. The recent progress in the field of structural coloration, particularly reflective coloration, offering a full‐color gamut, has realized high‐resolution printing, not attainable by the pigment paints. Herein, an overview of the various systems able to offer reflective coloration for a variety of optical applications with static and dynamic responses is presented. Specifically, an emphasis is given to recent works of the article's authors on the cooperative action of the disordered particles and dipoles that can generate specular reflective colors. In addition, further developments of reflective color nanosystems are discussed. In the first section, an overview of the recent progress in the field of plasmonic reflective structural coloration is provided. The second part of the article deals with the authors’ latest findings with respect to polarizonic color generation and its implementation in various areas ranging from environmental detection and biosensing to colored solar perfect absorbers. The report is wrapped up with an outlook and summary

    The Electrospun Ceramic Hollow Nanofibers

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    Hollow nanofibers are largely gaining interest from the scientific community for diverse applications in the fields of sensing, energy, health, and environment. The main reasons are: their extensive surface area that increases the possibilities of engineering, their larger accessible active area, their porosity, and their sensitivity. In particular, semiconductor ceramic hollow nanofibers show greater space charge modulation depth, higher electronic transport properties, and shorter ion or electron diffusion length (e.g., for an enhanced charging–discharging rate). In this review, we discuss and introduce the latest developments of ceramic hollow nanofiber materials in terms of synthesis approaches. Particularly, electrospinning derivatives will be highlighted. The electrospun ceramic hollow nanofibers will be reviewed with respect to their most widely studied components, i.e., metal oxides. These nanostructures have been mainly suggested for energy and environmental remediation. Despite the various advantages of such one dimensional (1D) nanostructures, their fabrication strategies need to be improved to increase their practical use. The domain of nanofabrication is still advancing, and its predictable shortcomings and bottlenecks must be identified and addressed. Inconsistency of the hollow nanostructure with regard to their composition and dimensions could be one of such challenges. Moreover, their poor scalability hinders their wide applicability for commercialization and industrial use

    Nanotheranostics: A Possible Solution for Drug-Resistant Staphylococcus aureus and their Biofilms?

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    Staphylococcus aureus is a notorious pathogen that colonizes implants (orthopedic and breast implants) and wounds with a vicious resistance to antibiotic therapy. Methicillin-resistant S. aureus (MRSA) is a catastrophe mainly restricted to hospitals and emerged to community reservoirs, acquiring resistance and forming biofilms. Treating biofilms is problematic except via implant removal or wound debridement. Nanoparticles (NPs) and nanofibers could combat superbugs and biofilms and rapidly diagnose MRSA. Nanotheranostics combine diagnostics and therapeutics into a single agent. This comprehensive review is interpretative, utilizing mainly recent literature (since 2016) besides the older remarkable studies sourced via Google Scholar and PubMed. We unravel the molecular S. aureus resistance and complex biofilm. The diagnostic properties and detailed antibacterial and antibiofilm NP mechanisms are elucidated in exciting stories. We highlight the challenges of bacterial infections nanotheranostics. Finally, we discuss the literature and provide “three action appraisals”. (i) The first appraisal consists of preventive actions (two wings), avoiding unnecessary hospital visits, hand hygiene, and legislations against over-the-counter antibiotics as the general preventive wing. Our second recommended preventive wing includes preventing the adverse side effects of the NPs from resistance and toxicity by establishing standard testing procedures. These standard procedures should provide breakpoints of bacteria’s susceptibility to NPs and a thorough toxicological examination of every single batch of synthesized NPs. (ii) The second appraisal includes theranostic actions, using nanotheranostics to diagnose and treat MRSA, such as what we call “multifunctional theranostic nanofibers. (iii) The third action appraisal consists of collaborative actions

    Nanotheranostics: A Possible Solution for Drug-Resistant Staphylococcus aureus and their Biofilms?

    Get PDF
    Staphylococcus aureus is a notorious pathogen that colonizes implants (orthopedic and breast implants) and wounds with a vicious resistance to antibiotic therapy. Methicillin-resistant S. aureus (MRSA) is a catastrophe mainly restricted to hospitals and emerged to community reservoirs, acquiring resistance and forming biofilms. Treating biofilms is problematic except via implant removal or wound debridement. Nanoparticles (NPs) and nanofibers could combat superbugs and biofilms and rapidly diagnose MRSA. Nanotheranostics combine diagnostics and therapeutics into a single agent. This comprehensive review is interpretative, utilizing mainly recent literature (since 2016) besides the older remarkable studies sourced via Google Scholar and PubMed. We unravel the molecular S. aureus resistance and complex biofilm. The diagnostic properties and detailed antibacterial and antibiofilm NP mechanisms are elucidated in exciting stories. We highlight the challenges of bacterial infections nanotheranostics. Finally, we discuss the literature and provide “three action appraisals”. (i) The first appraisal consists of preventive actions (two wings), avoiding unnecessary hospital visits, hand hygiene, and legislations against over-the-counter antibiotics as the general preventive wing. Our second recommended preventive wing includes preventing the adverse side effects of the NPs from resistance and toxicity by establishing standard testing procedures. These standard procedures should provide breakpoints of bacteria’s susceptibility to NPs and a thorough toxicological examination of every single batch of synthesized NPs. (ii) The second appraisal includes theranostic actions, using nanotheranostics to diagnose and treat MRSA, such as what we call “multifunctional theranostic nanofibers. (iii) The third action appraisal consists of collaborative actions

    Ups and Downs of Water Photodecolorization by Nanocomposite Polymer Nanofibers

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    Given the exponentially expanding water pollution causing water scarcity, there is an urgent need for operative nanotechnological systems that can purify water, with insignificant energy consumption, and rapidly. Here, we introduce a nanocomposite system based on TiO 2 nanoparticles (NPs) and PES nanofibers (NFs) that can adsorb and then photodecompose organic water pollutants such as dye molecules. We evaluate pros and cons of this system with respect to its purification efficiency and structural properties that can be impacted by the photocatalytic activity of the nanofillers. While the material is superhydrophilic and able to remove 95% methylene blue (MB) from water via adsorption/photodecomposition, its thermomechanical properties decline upon UV irradiation. However, these properties still remain at the level of the neat NFs. The removal behavior is modeled by the first-and second-order kinetic models from the kinetic point of view. The nanocomposite NFs’ removal behavior complies much better with the second-order kinetic model. Overall, such feedbacks implied that the nanocomposite can be effectively applied for water treatment and the structural properties are still as reliable as those of the neat counterpart.Peer reviewe

    Biosynthesis of Zinc Oxide Nanoparticles on l-Carnosine Biofunctionalized Polyacrylonitrile Nanofibers: a Biomimetic Wound Healing Material

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    Multifunctional biohybrid nanofibers (NFs) that can simultaneously drive various cellular activities and confer antibacterial properties are considered desirable in producing advanced wound healing materials. In this study, a bionanohybrid formulation was processed as a NF wound dressing to stimulate the adhesion and proliferation of fibroblast and endothelial cells that play a major role in wound healing. Polyacrylonitrile (PAN) electrospun NFs were hydrolyzed using NaOH and biofunctionalized with l-carnosine (CAR), a dipeptide which could later biosynthesize zinc oxide (ZnO) nanoparticles (NPs) on the NFs surface. The morphological study verified that ZnO NPs are uniformly distributed on the surface of CAR/PAN NFs. Through EDX and XRD analysis, it was validated that the NPs are composed of ZnO and/or ZnO/Zn(OH)2. The presence of CAR and ZnO NPs brought about a superhydrophilicity effect and notably raised the elastic modulus and tensile strength of Zn-CAR/PAN NFs. While CAR ligands were shown to improve the viability of fibroblast (L929) and endothelial (HUVEC) cells, ZnO NPs lowered the positive impact of CAR, most likely due to their repulsive negative surface charge. A scratch assay verified that CAR/PAN NFs and Zn-CAR/PAN NFs aided HUVEC migration more than PAN NFs. Also, an antibacterial assay implied that CAR/PAN NFs and Zn-CAR/PAN NFs are significantly more effective in inhibiting Staphylococcus aureus (S. aureus) than neat PAN NFs are (1000 and 500%, respectively). Taken together, compared to the neat PAN NFs, CAR/PAN NFs with and without the biosynthesized ZnO NPs can support the cellular activities of relevance for wound healing and inactivate bacteria
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