Investigation of metallic nanoparticle distribution in PAN/magnetic nanocomposites fabricated with needleless electrospinning technique

Needleless electrospinning can be used to produce polyacrylonitrile nanofibres, for example, to which magnetic nanoparticles can additionally be added. Such composite nanofibres can then be stabilised and carbonised to produce carbon composite nanofibres. The magnetic nanoparticles have an influence not only on the structure but also on the mechanical and electrical properties of the finished carbon nanofibres, as does the heat treatment during stabilisation and incipient carbonisationThe present study reports on the fabrication, heat treatment and resulting properties of poly(acrylonitrile) (PAN)/magnetic nanofibre mats prepared by needleless electrospinning from polymer solutions. A variety of microscopic and thermal characterisation methods were used to investigate in detail the chemical and morphological transition during oxidative stabilisation (280 °C) and incipient carbonisation (500 °C). PAN and nanoparticles were analysed during all stages of heat treatment. Compared to pure PAN nanofibres, the PAN/ magnetic nanofibers showed larger fiber diameters and the presence of beads and agglomerations. In this study, magnetic nanofibers were investigated in more detail with the aim of detecting undesired agglomerations. Visual observation, for example with CLSM or SEM, does not provide conclusive evidence of agglomerations in the nanofibers. But based on the capabilities of SEM/EDS many different types of samples can be easily analysed where other analytical techniques simply cannot give the fast answer.

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Needleless electrospinning of PVP/PGS fibrous scaffolds for skin tissue engineering applications

10.31224/osf.io/xs64k ◽

2018 ◽

Cited By ~ 1

Author(s):

Antonios Keirouz ◽

Giuseppino Fortunato ◽

Anthony Callanan ◽

Norbert Radacsi

Keyword(s):

Tissue Engineering ◽

Tensile Modulus ◽

Dermal Fibroblasts ◽

Skin Tissue ◽

Skin Substitute ◽

Electrospinning Technique ◽

Skin Tissue Engineering ◽

Needleless Electrospinning ◽

High Concentrations

Scaffolds and implants used for tissue engineering need to be adapted for their mechanical properties with respect to their environment within the human body. Therefore, a novel composite for skin tissue engineering is presented by use of blends of Poly(vinylpyrrolidone) (PVP) and Poly(glycerol sebacate) (PGS) were fabricated via the needleless electrospinning technique. The formed PGS/PVP blends were morphologically, thermochemically and mechanically characterized. The morphology of the developed fibers related to the concentration of PGS, with high concentrations of PGS merging the fibers together plasticizing the scaffold. The tensile modulus appeared to be affected by the concentration of PGS within the blends, with an apparent decrease in the elastic modulus of the electrospun mats and an exponential increase of the elongation at break. Ultraviolet (UV) crosslinking of PGS/PVP significantly decreased and stabilized the wettability of the formed fiber mats, as indicated by contact angle measurements. In vitro examination showed good viability and proliferation of human dermal fibroblasts over the period of a week. The present findings provide important insights for tuning the elastic properties of electrospun material by incorporating this unique elastomer, as a promising future candidate for skin substitute constructs.

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Preparation of Titanium Dioxide Nanoparticles Immobilized on Polyacrylonitrile Nanofibres for the Photodegradation of Methyl Orange

International Journal of Photoenergy ◽

10.1155/2016/3162976 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Pardon Nyamukamba ◽

Omobola Okoh ◽

Lilian Tichagwa ◽

Corinne Greyling

Keyword(s):

Electron Microscopy ◽

Titanium Dioxide ◽

Methyl Orange ◽

Organic Contaminants ◽

Uv Light ◽

Titanium Dioxide Nanoparticles ◽

Xrd Analysis ◽

Rutile Phase ◽

Electrospinning Technique ◽

Carbon Nanofibres

Herein, we describe the synthesis of titanium dioxide (TiO2) nanoparticles by the hydrolysis and condensation of titanium tetrachloride. The resulting nanoparticles were immobilized on polyacrylonitrile (PAN) based nanofibres by an electrospinning technique in order to allow simple isolation and reuse of titania semiconductor photocatalyst. The composite nanofibres were heat treated to convert the polymer nanofibres to carbon nanofibres and to convert amorphous TiO2to crystalline TiO2. X-ray diffraction (XRD) analysis showed that the rutile phase was the major phase and the equatorial peaks of PAN disappeared after heat treatment at 600°C. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analysis confirmed that some TiO2nanoparticles were encapsulated whereas some were surface residing on the electrospun nanofibres. The TiO2nanoparticles were found to lower the cyclization temperature of PAN as indicated by differential scanning colorimetry (DSC) and differential thermal analysis (DTA). Photocatalytic studies on the degradation of methyl orange dye under UV light irradiation showed that composite nanofibres were capable of degrading organic contaminants in water. The carbon nanofibres with surface residing titanium dioxide nanoparticles (TiO2/CNF-SR) showed the highest photocatalytic activity (59.35% after 210 minutes) due to direct contact between the TiO2photocatalyst and methyl orange.

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Effect of aluminum doped iron oxide nanoparticles on magnetic properties of the polyacrylonitrile nanofibers

Journal of Polymer Engineering ◽

10.1515/polyeng-2015-0303 ◽

2017 ◽

Vol 37 (2) ◽

pp. 135-141

Author(s):

Armin Ourang ◽

Soheil Pilehvar ◽

Mehrzad Mortezaei ◽

Roya Damircheli

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Magnetic Nanoparticles ◽

Iron Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

Negative Interaction ◽

Magnetic Nanofibers

Abstract In this work, polyacrylonitrile (PAN) was electrospun with and without magnetic nanoparticles (aluminum doped iron oxide) and was turned into magnetic nanofibers. The results showed that nanofibers diameter decreased from 700 nm to 300 nm by adding nanoparticles. Furthermore, pure PAN nanofibers were indicated to have low magnetic ability due to polar bonds that exist in their acrylonitrile groups. Obviously by adding only 4 wt% of the nanoparticles to PAN nanofibers, magnetic ability soared by more than 10 times, but at a higher percentage, it was shown to change just a little due to negative interaction among nanoparticles. This event relates to antiferromagnetically coupling of nanoparticles due to incomplete dispersion at higher percentage.

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Study of the phase transition ability of coal tar pitch and their coke products under the influence of temperature used to synthesise carbon composite materials

Ministry of Science and Technology, Vietnam ◽

10.31276/vjst.63(11db).56-59 ◽

2021 ◽

Vol 63 (11) ◽

pp. 56-59

Author(s):

The Nam Dao ◽

◽

Minh Thanh Vu ◽

Tuan Anh Doan ◽

Thi Thao Vu ◽

...

Keyword(s):

Heat Treatment ◽

Coal Tar ◽

Amorphous State ◽

Carbon Composite ◽

Coal Tar Pitch ◽

Carbon Fabric ◽

Scanning Calorimetry ◽

Pitch Sample ◽

Carbon Composite Material ◽

Carbon Composite Materials

Using differential scanning calorimetry and thermogravimetric analysis showed the marking temperature of coal tar pitch is 107.8°C. The thermal decomposition of the pitch is divided into three main stages, corresponding to three phases α, β, γ, with a coke yield of 47% at 800°C. The change in the XRD diagram showed a clear transition from the amorphous state of carbon to the highly ordered crystalline structure of graphite after treatment at 2,200 and 2,700°С. The purity of the pitch sample and the structure of the CCC carbon-carbon composite material after heat treatment at 2,700°C were studied using scanning electron microscopy and energy-dispersive X-ray spectroscopy methods. The results showed that after heat treatment, the C content in the sample reached more than 99.5%, and the coke residues after graphitization were bound and connected to the carbon fabric into a mass of graphite material.

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Characterization of intratumor magnetic nanoparticle distribution and heating in a rat model of metastatic spine disease

Journal of Neurosurgery Spine ◽

10.3171/2014.2.spine13142 ◽

2014 ◽

Vol 20 (6) ◽

pp. 740-750 ◽

Cited By ~ 14

Author(s):

Patricia L. Zadnik ◽

Camilo A. Molina ◽

Rachel Sarabia-Estrada ◽

Mari L. Groves ◽

Michele Wabler ◽

...

Keyword(s):

Magnetic Nanoparticles ◽

Inductively Coupled Plasma ◽

Magnetic Nanoparticle ◽

Systemic Exposure ◽

Neurological Dysfunction ◽

Spinal Tumors ◽

Nanoparticle Distribution ◽

Inductively Coupled ◽

Plasma Mass Spectrometry ◽

Histopathological Studies

Object The goal of this study was to optimize local delivery of magnetic nanoparticles in a rat model of metastatic breast cancer in the spine for tumor hyperthermia while minimizing systemic exposure. Methods A syngeneic mammary adenocarcinoma was implanted into the L-6 vertebral body of 69 female Fischer rats. Suspensions of 100-nm starch-coated iron oxide magnetic nanoparticles (micromod Partikeltechnologie GmbH) were injected into tumors 9 or 13 days after implantation. For nanoparticle distribution studies, tissues were harvested from a cohort of 36 rats, and inductively coupled plasma mass spectrometry and histopathological studies with Prussian blue staining were used to analyze the samples. Intratumor heating was tested in 4 anesthetized animals with a 20-minute exposure to an alternating magnetic field (AMF) at a frequency of 150 kHz and an amplitude of 48 kA/m or 63.3 kA/m. Intratumor and rectal temperatures were measured, and functional assessments of AMF-exposed animals and histopathological studies of heated tumor samples were examined. Rectal temperatures alone were tested in a cohort of 29 rats during AMF exposure with or without nanoparticle administration. Animal studies were completed in accordance with the protocols of the University Animal Care and Use Committee. Results Nanoparticles remained within the tumor mass within 3 hours of injection and migrated into the bone at 6, 12, and 24 hours. Subarachnoid accumulation of nanoparticles was noted at 48 hours. No evidence of lymphoreticular nanoparticle exposure was found on histological investigation or via inductively coupled plasma mass spectrometry. The mean intratumor temperatures were 43.2°C and 40.6°C on exposure to 63.3 kA/m and 48 kA/m, respectively, with histological evidence of necrosis. All animals were ambulatory at 24 hours after treatment with no evidence of neurological dysfunction. Conclusions Locally delivered magnetic nanoparticles activated by an AMF can generate hyperthermia in spinal tumors without accumulating in the lymphoreticular system and without damaging the spinal cord, thereby limiting neurological dysfunction and minimizing systemic exposure. Magnetic nanoparticle hyperthermia may be a viable option for palliative therapy of spinal tumors.

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Effect of heat treatment of carbon nanofibres on electroless copper deposition

Composites Science and Technology ◽

10.1016/j.compscitech.2010.07.015 ◽

2010 ◽

Vol 70 (16) ◽

pp. 2269-2275 ◽

Cited By ~ 14

Author(s):

J. Tamayo-Ariztondo ◽

J.M. Córdoba ◽

M. Odén ◽

J.M. Molina-Aldareguia ◽

M.R. Elizalde

Keyword(s):

Heat Treatment ◽

Copper Deposition ◽

Carbon Nanofibres ◽

Electroless Copper

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Synthesis and characterization of electrospun molybdenum dioxide–carbon nanofibers as sulfur matrix additives for rechargeable lithium–sulfur battery applications

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.28 ◽

2018 ◽

Vol 9 ◽

pp. 262-270 ◽

Cited By ~ 16

Author(s):

Ruiyuan Zhuang ◽

Shanshan Yao ◽

Maoxiang Jing ◽

Xiangqian Shen ◽

Jun Xiang ◽

...

Keyword(s):

Electron Microscopy ◽

Heat Treatment ◽

Electrochemical Performance ◽

Carbon Nanofibers ◽

Lithium Ion ◽

Cycle Performance ◽

Bet Surface Area ◽

Molybdenum Dioxide ◽

Electrospinning Technique ◽

Lithium Sulfur

One-dimensional molybdenum dioxide–carbon nanofibers (MoO2–CNFs) were prepared using an electrospinning technique followed by calcination, using sol–gel precursors and polyacrylonitrile (PAN) as a processing aid. The resulting samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Brunauer–Emmet–Teller (BET) surface area measurements, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). MoO2–CNFs with an average diameter of 425–575 nm obtained after heat treatment were used as a matrix to prepare sulfur/MoO2–CNF cathodes for lithium–sulfur (Li–S) batteries. The polysulfide adsorption and electrochemical performance tests demonstrated that MoO2–CNFs did not only act as polysulfide reservoirs to alleviate the shuttle effect, but also improve the electrochemical reaction kinetics during the charge–discharge processes. The effect of MoO2–CNF heat treatment on the cycle performance of sulfur/MoO2–CNFs electrodes was examined, and the data showed that MoO2–CNFs calcined at 850 °C delivered optimal performance with an initial capacity of 1095 mAh g−1 and 860 mAh g−1 after 50 cycles. The results demonstrated that sulfur/MoO2–CNF composites display a remarkably high lithium–ion diffusion coefficient, low interfacial resistance and much better electrochemical performance than pristine sulfur cathodes.

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Influence of Magnetic Scaffold Loading Patterns on their Hyperthermic Potential against Bone Tumors

10.36227/techrxiv.15098061 ◽

2021 ◽

Author(s):

Matteo Bruno Lodi ◽

Nicola Curreli ◽

Sonia Zappia ◽

Luca Pilia ◽

Maria Francesca Casula ◽

...

Keyword(s):

Spatial Distribution ◽

Magnetic Nanoparticles ◽

Magnetic Measurements ◽

Casting Process ◽

Hyperthermia Treatment ◽

Morphological Alterations ◽

Nanoparticle Distribution ◽

Tumor Hyperthermia ◽

Loading Patterns ◽

Poly Caprolactone

Magnetic scaffolds have been investigated as promising tools for the interstitial hyperthermia treatment of bone cancers, to control local recurrence by enhancing radio- and chemotherapy effectiveness. The potential of magnetic scaffolds motivates the development of production strategies enabling tunability of the resulting magnetic properties. Within this framework, deposition and drop-casting of magnetic nanoparticles on suitable scaffolds offer advantages such as ease of production and high loading, although these approaches are often associated with a non-uniform final spatial distribution of nanoparticles in the biomaterial. The implications and the influences of nanoparticle distribution on the final therapeutic application have not yet been investigated thoroughly. In this work, poly-caprolactone scaffolds are magnetized by loading them with synthetic magnetic nanoparticles through a drop-casting deposition and tuned to obtain different distributions of magnetic nanoparticles in the biomaterial. The physicochemical properties of the magnetic scaffolds are analyzed. The microstructure and the morphological alterations due to the reworked drop-casting process are evaluated and correlated to static magnetic measurements. THz tomography is used as an investigation technique to derive the spatial distribution of nanoparticles. Finally, in silico multiphysics experiments are used to investigate the influence on the loading patterns on the interstitial bone tumor hyperthermia treatment.

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Needleless Electrospinning of Polystyrene Fibers with an Oriented Surface Line Texture

Journal of Nanomaterials ◽

10.1155/2012/473872 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Chen Huang ◽

Haitao Niu ◽

Jinglei Wu ◽

Qinfei Ke ◽

Xiumei Mo ◽

...

Keyword(s):

Large Scale ◽

Early Stage ◽

Fiber Surface ◽

Diameter Distribution ◽

X Ray Diffraction ◽

Electrospinning Technique ◽

X Ray ◽

Needleless Electrospinning ◽

Significant Difference ◽

Line Texture

We have demonstrated that polystyrene (PS) nanofibers having an ordered surface line texture can be produced on a large scale from a PS solution of acetone and N,N′-dimethylformamide (2/1, vol/vol) by a needleless electrospinning technique using a disc as fiber generator. The formation of the unusual surface feature was investigated and attributed to the voids formed on the surface of jets due to the fast evaporation of acetone at the early stage of electrospinning, and subsequent elongation and solidification turning the voids into ordered lines on fiber surface. In comparison with the nanofibers electrospun by a conventional needle electrospinning using the same solution, the disc electrospun fibers were finer with similar diameter distribution. The fiber production rate for the disc electrospinning was 62 times higher than that of the conventional electrospinning. Fourier transform infrared spectroscopy and X-ray diffraction measurements indicated that the PS nanofibers produced from the two electrospinning techniques showed no significant difference in chemical component, albeit slightly higher crystallinity in the disc spun nanofibers.

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