Electrospinning Research Papers - Academia.edu (original) (raw)

The bio/sensors performance has been established to be significantly affected through partially or entirely alignment of nano/microfibrous in polymeric mats. The matter of crystalline/amorphous proportion in semicrystalline polymers is... more

The bio/sensors performance has been established to be significantly affected through partially or entirely alignment of nano/microfibrous in polymeric mats. The matter of crystalline/amorphous proportion in semicrystalline polymers is another factor that can affect the application of the piezoelectric patches. The present work deals with fabricating
the scaffolds of micro/nanofibers through a modified electrospinning procedure. The ratio of the relevant organic and polar solvents, the beading, the degree of fiber alignment, and fiber thickness have been intentionally elaborated. An unaligned unbeaded nanofibrous
mat has been fabricated after tuning the solvents to poly-lactic acid ratio. This paper, for the first time, deals with the calculation of the value of d33 value of a commercial PLA and its improvement, it has been revealed that the d33 piezoelectric property is improved as a
consequence of the thermo-mechanical processing above the cold crystallization temperature. The applied thermo (mechanical) processing causes the structural evolution from amorphous to crystallized states. Formation of the a and a0 crystalline phases is introduced
as the main responsible for the improvement of the piezoelectric property. This improvement not only is correlated with the degree of crystallinity, but also the orientation and alignment of the crystallites is known to be influential. In this respect, the complex helical chain structural evolution of poly-lactic acid has been analyzed through Herman's orientation function. It has been found that, besides the characterized disorder-to-order phase transformation, the C]O branched out dipoles interactions significantly affects by the texturization of the aligned polymeric chains in the direction of the electrospinning
which is known as the main factor to promote the piezoelectric property of processed mat.

A novel high-performance polyamide 6, polyacrylonitrile and polyvinylidene fluoride nanofibers were fabricated using industrial production Nanospider equipment for liquid filtration as microfilters. The application of nanofibers has been... more

A novel high-performance polyamide 6, polyacrylonitrile and polyvinylidene fluoride nanofibers were fabricated using industrial production Nanospider equipment for liquid filtration as microfilters. The application of nanofibers has been hindered by their poor mechanical strength. This work developed a feasible approach to preparing mechanically strong nanofiber webs. The mechanical strength of the nanofibers was enhanced using special lamination technique on a supporting layer. Experimental results show that the mechanical strength of the nanofibers enhanced more than 5 times while high porosity and liquid permeability retain. The separation results indicate that nanofibers have a potential to be used in liquid filters.

The electrospinning of polymers has become a potentially important process for the production of tissue engineering scaffolds. CO2 impregnation of these scaffolds may provide a method for tailoring the chemistry of these relatively high... more

The electrospinning of polymers has become a potentially important process for the production of tissue engineering scaffolds. CO2 impregnation of these scaffolds may provide a method for tailoring the chemistry of these relatively high surface area scaffolds without altering their biomimetic architecture. In pursuing this we found that electrospun polycaprolactone (PCL) fibers melt when exposed to supercritical CO2 even at

The development of smart negative electrode materials with high capacitance for the uses in supercapacitors remains challenging. Although several types of electrode materials with high capacitance in energy storage have been reported,... more

The development of smart negative electrode materials with high capacitance for the uses in supercapacitors remains challenging. Although several types of electrode materials with high capacitance in energy storage have been reported, carbon-based materials are the most reliable electrodes due to their high conductivity, high power density, and excellent stability. The most common complaint about general carbon materials is that these electrode materials can hardly ever be used as free-standing electrodes. Free-standing carbon-based electrodes are in high demand and are a passionate topic of energy storage research. Electrospun nanofibers are a potential candidate to fill this gap. However, the as-spun carbon nanofibers (ECNFs) have low capacitance and low energy density on their own. To overcome the limitations of pure CNFs, increasing surface area, heteroatom doping and metal doping have been chosen. In this review, we introduce the negative electrode materials that have been deve...

Nanofibers made in the electrospinning process have a very interesting set of material properties that are beneficial for many applications. Despite many existing commercial solutions, there are still some problems that need to be solved... more

Nanofibers made in the electrospinning process have a very interesting set of material properties that are beneficial for many applications. Despite many existing commercial solutions, there are still some problems that need to be solved to improve the quality of obtained materials as well as overall process performance. For example, an irregularity of the electric field intensity distribution along the collector surface, resulting in an irregular distribution of nanofibers decreases the efficiency of the electrospinning process. Moreover, it also leads to the generation of coarser nanofibers from the middle part of the cylinder surface in comparison to those produced at the cylinder ends. The numerical simulations of the electrospinning process applying infinite domains using the finite element method presented in this paper provide effective methods to improve the distribution of the electric field intensity on the collector, which has a direct impact on the obtained structure of nanofibers.

Comparative statistical analysis of the infiuence of processing parameters, for electrospinning (ES) and solution blow spinning (SBS) processes, on nanofibrous poly(L-lactic acid) (PLLA) material morphology and average fiber diameter was... more

Comparative statistical analysis of the infiuence of processing parameters, for electrospinning (ES) and solution blow spinning (SBS) processes, on nanofibrous poly(L-lactic acid) (PLLA) material morphology and average fiber diameter was conducted in order to identify the key processing parameter for tailoring the product properties. Further, a comparative preliminary biocompatibility evaluation was performed. Based on Design of Experiment (DOE) principles, analysis of standard effects of voltage, air pressure, solution feed rate and concentration, on nanofibers average diameter was performed with the Pareto’s charts and the best fitted surface charts. Nanofibers were analyzed by scanning electron microscopy (SEM). The preliminary biocompatibility comparative tests were performed based on SEM microphotographs of CP5 cells cultured on materials derived from ES and SBS. Polymer solution concentration was identified as the key parameter infiuencing morphology and dimensions of nanofibr...

In this study, erbia (Er2O3)-doped Bi2O3 ceramics were prepared from sol–gel derived nanocrystalline powders. The morphological properties were investigated by scanning electron microscopy. X-ray diffraction (XRD) analysis was carried out... more

In this study, erbia (Er2O3)-doped Bi2O3 ceramics were prepared from sol–gel derived nanocrystalline powders. The morphological properties were investigated by scanning electron microscopy. X-ray diffraction (XRD) analysis was carried out in order to characterize the phase and crystal structure of the powder samples. Temperature dependent electrical properties were determined by thermogravimetry/differential thermal analyzer (TG/DTA) and 4-point probe techniques. The stable fluorite face centered cubic δ-type phase was observed at room temperature from the XRD result, which was supported by the DTA and temperature dependent electrical conductivity measurements. Electrical conductivity results indicate that there is a transition approximately at 650 °C, which can be attributed to an order–disorder transition (ODT). The activation energy values obtained from the Arrhenius approach for heating and cooling process were presented. Two regimes, corresponding to high temperature region (HTR) and low temperature region (LTR), were observed. As a result of morphological changes during the ODT, the electrical conductivity modifies and the activation energies are different for studied sample at HTR and LTR.

Biocompatible poly(vinyl alcohol)/poly (vinylpyrrolidone) iodine/poly(ethylene glycol) fibers containing (hydroxypropyl)methyl cellulose (HPMC) and aloe vera were successfully prepared by electrospinning their aqueous solution. Aloe vera... more

Biocompatible poly(vinyl alcohol)/poly (vinylpyrrolidone) iodine/poly(ethylene glycol) fibers containing (hydroxypropyl)methyl cellulose (HPMC) and aloe vera were successfully prepared by electrospinning their aqueous solution. Aloe vera which is known to be effective in the treatment of various wounds was added to the polymer solution. HPMC was added to the system as the water retention agent. The hybrid fiber mats were subjected to detailed analysis using a differential scanning calorimeter, a scanning electron microscope (SEM), and a Fourier transform infrared spectrometer. Images obtained from the SEM showed that the polymer fibers were linear, homogenous, and contained no beading. The fiber diameters ranged between 100 and 900 nm. It was seen that the electrospun mats obtained could potentially be used as a material for dressing wounds. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polyethylene glycol diacrylate (PEGDA) is an important class of photosensitive polymer with many tissue engineering applications. This study compared PEGDA and polycaprolactone (PCL) nanofiber matrix (NFM) coated PEGDA, referred to as... more

Polyethylene glycol diacrylate (PEGDA) is an important class of photosensitive polymer with many tissue engineering applications. This study compared PEGDA and polycaprolactone (PCL) nanofiber matrix (NFM) coated PEGDA, referred to as PCL-PEGDA, scaffolds for their application in multiple tissue repair such as articular cartilage, nucleus pulposus of the intervertebral disc (IVD). We examined each scaffold morphology, porosity, swelling ratio, degradation, mechanical strength, and in vitro cytocompatibility properties. A defect was created in Sprague Dawley rat tail IVD by scraping native cartilage tissue and disc space, then implanting the scaffolds in the disc space for 4 weeks to evaluate in vivo efficacy of multi-tissue repair. Maintenance of disc height and creation of a new cell matrix was assessed to evaluate each scaffold’s ability to repair the tissue defect. Although both PEGDA and PCL-PEGDA scaffolds showed similar porosity ∼73%, we observed distinct topographical charact...

The use of electrospun fibers as drug carriers could be promising in the future for biomedical applications, especially postoperative local chemotherapy. In this research work, electrospun fibers were developed as a new system for the... more

The use of electrospun fibers as drug carriers could be promising in the future for biomedical applications, especially postoperative local chemotherapy. In this research work, electrospun fibers were developed as a new system for the delivery of ketoprofen as non-steroidal anti-inflammatory drug (NSAID). The fibers were made either from polycaprolactone (PCL) as a biodegradable polymer or polyurethane (PU) as a non-biodegradable polymer, or from the blends of the two. The release of the ketoprofen was followed by UV–vis spectroscopy in phosphate buffer of pH 7.4 at 37 and 20 °C.The results showed that the release rates from the polycaprolactone, polyurethane and their blend are similar. However, the blend of the polycaprolactone with polyurethane improved its visual mechanical properties. Release profiles from the electrospun mats were compared to cast films of the various formulations.

Visible light-sensitive carbon doped titanium dioxide nanoparticles (C-TiO2) were prepared by a sol-gel method. The carbon dopant was obtained from glucose. The dopant level incorporated into the TiO2 lattice structure was varied by using... more

Visible light-sensitive carbon doped titanium dioxide nanoparticles (C-TiO2) were prepared by a
sol-gel method. The carbon dopant was obtained from glucose. The dopant level incorporated into
the TiO2 lattice structure was varied by using different concentrations of the carbon source solution.
The nanoparticles were characterized by X-ray diffraction (XRD), BET Surface area, Scanning
electron microscopy (SEM), Transmission electron microscopy (TEM), Scanning X-ray
photoelectron spectroscopy (SXPS) and Diffuse reflectance spectroscopy (DRS). The presence of
carbon in the TiO2 lattice was determined by SXPS. The DRS results revealed that carbon doping
reduced the band gap of TiO2. Doping was also found to cause a reduction in the particle size of the
TiO2 nanoparticles and enhance anatase to rutile phase transformation. The photocatalytic activities
of the prepared samples were evaluated by the photocatalytic degradation of methyl orange. The
carbon doped TiO2 showed a higher photocatalytic activity than degussa P25 and undoped TiO2.

Electrospinning has attracted a worldwide interest as a technique for the production of nanofibrous membranes with diameter ranging 2 nm to several microscales using natural and synthetic polymers. The electrospun nanofibres have... more

Electrospinning has attracted a worldwide interest as a technique for the production of nanofibrous membranes with diameter
ranging 2 nm to several microscales using natural and synthetic polymers. The electrospun nanofibres have advantages such
as high surface area, easy surface modification, functionalization of polymeric chains, inexpensive and tunable thermomechanical
properties. Moreover, electrospinning is one of the simplest techniques for the incorporation of nanofillers
into polymeric nanofibres. Herein, we review the preparation and applications of natural and polymer-based nanofibrous
membranes. We focus on applications of the electrospun membrane for energy storage, water purification and biomedical.
Furthermore, we show surface morphologies of nanofibrous membranes using fast emission scanning electron microscopy,
transmission electron microscopy, atomic force microscopy, Brunauer–Emmett–Teller and micrographs.

Electrospinning is a versatile technique for generating a mat of continuous fibers with diameters from a few nanometers to several micrometers. The diversity of electrospinnable materials, and the unique features associated with... more

Electrospinning is a versatile technique for generating a mat of continuous fibers with diameters from a few nanometers to several micrometers. The diversity of electrospinnable materials, and the unique features associated with electro-spun fibers make this technique and its resultant structures attractive for applications in the biomedical field. This article presents an overview of this technique focusing on its application for tissue engineering. In particular, the advantages and disadvantages of using an electrospinning mat for biomedical applications are discussed. It reviews the different available electrospinning configurations, detailing how the different process variables and material types determine the obtained fibers characteristics. Then a description of how nanofiber based scaffolds offer great promise in the regener-ation or function restoration of damaged or diseased bones, muscles or nervous tissue is reported. Different methods for incorporating active agents on nanofibers and controlling their release mechanisms are also reviewed. The review concludes with some personal perspectives on the future work to be done in order to include electrospinning technique in the industrial development of biomedical materials.

Significant progress has been made recently in the fabrication of polymeric nanofibers, their characterization and applications, new polymeric materials, theoretical analysis, and so forth. Hence, in this brief review, we report the... more

Significant progress has been made recently in the fabrication of polymeric nanofibers, their characterization and applications, new polymeric materials, theoretical analysis, and so forth. Hence, in this brief review, we report the progress made in these subjects during the last 5 years. Most of the work concerns nanofibers related to the field of medicine. On the other hand, negligibly few reports have been found on nanofibers related to membrane separation processes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Electrospinning is a versatile technique that has gained popularity for various biomedical applications in recent years. Electrospinning is being used for fabricating nanofibers for various biomedical and dental applications such as tooth... more

Electrospinning is a versatile technique that has gained popularity for various biomedical applications in recent years. Electrospinning is being used for fabricating nanofibers for various biomedical and dental applications such as tooth regeneration, wound healing and prevention of dental caries. Electrospun materials have the benefits of unique properties for instance, high surface area to volume ratio, enhanced cellular interactions, protein absorption to facilitate binding sites for cell receptors. Extensive research has been conducted to explore the potential of electrospun nanofibers for repair and regeneration of various dental and oral tissues including dental pulp, dentin, periodontal tissues, oral mucosa and skeletal tissues. However, there are a few limitations of electrospinning hindering the progress of these materials to practical or clinical applications. In terms of biomaterials aspects, the better understanding of controlled fabrication, properties and functioning of electrospun materials is required to overcome the limitations. More in vivo studies are definitely required to evaluate the biocompatibility of electrospun scaffolds. Furthermore, mechanical properties of such scaffolds should be enhanced so that they resist mechanical stresses during tissue regeneration applications. The objective of this article is to review the current progress of electrospun nanofibers for biomedical and dental applications. In addition, various aspects of electrospun materials in relation to potential dental applications have been discussed.

Nanofibers have superior physical and mechanical properties. Although nanofibers can be produced by several methods, the electrospinning is predominant method in terms of simplicity, fiber diameter, flexibility and morphology. Moreover,... more

Nanofibers have superior physical and mechanical properties. Although nanofibers can be produced by several methods, the electrospinning is predominant method in terms of simplicity, fiber diameter, flexibility and morphology. Moreover, usage nanofibers are generally produced as non-woven webs by electrospinning. This shape of production limits usage areas of nanofibers. Therefore, researchers have been working on electrospinning of nanofibers into yarns. The main aims of these studies are alignment and twisting of nanofibers. The usage areas of nanofibers will be increased by converting them into yarns from webs. Nanofibers in yarn formation can be used in several applications especially woven and knitted fabrics like convention yarns. The aim of this study is to analyze the studies about electrospun nanofiber yarn production in terms of twisting and winding mechanisms developments by years and also working principles and parameters of the electrospinning setups that are related to production of nanofiber yarn in the literature are compared. These studies are divided into two classes as discontinuous and continuous, both of them are divided into sub groups twisted and non-twisted systems. When nanofiber yarn production studies by electrospinning method are examined, it can be said that the continuous methods are advantageous compared to the discontinuous methods in terms of production speed. Twisted systems are more attractive because they give strength to the nanofiber yarn. Needless type feeders are more suitable for high speed production than needle type feeders that are used to decrease complexity of the process. In recent years, funnels, discs and cylinder types of twisting units have been preferred due to the advantages of easy installation and twisting control. As a result, systems that produce nanofiber yarns by electrospinning method are trending to industrial production that means they are focused on twisted and continuous nanofiber yarns.

The present study describes the processing and mechanical characterization of S-2 glass fiber with and without interleaved Ethyl Orthosilicate (TEOS) chemically engineered glass nanofibers manufactured using electrospinning technique with... more

The present study describes the processing and mechanical characterization of S-2 glass fiber with and without interleaved Ethyl Orthosilicate (TEOS) chemically engineered glass nanofibers manufactured using electrospinning technique with resin EPON 862 with EPIKURE curing agent W. The manufactured electrospun TEOS nanofiber were sintered to evaporate ethanol and reduce the fiber diameter so as to increase the surface area. The heated Vacuum assisted resin transfer molding (H-VARTM) method was used to fabricate the combined panel using same resin and equal flow and specimen were cut using the water jet machine as per the standards. Tension, compression, in plane shear, interlaminar shear and iosipecu test were conducted as per the accepted ASTM test standards. The mechanical properties strength, modulus, Poisson's ratio, shear modulus, fiber volume fraction ratios and densities are measured and corresponding modes of failure have been studied and compared with each other. The S-2 glass fibers with Electrospun TEOS nanofiber composite have shown significant improvement in the in plane shear strength and modulus and slightly improvement in the tensile properties. However lower the compression strength and modulus as well as shear modulus. Due to pre bend in the plies of the glass fiber and fold over elastic sizing are the possible reasons for reduction of compression properties. The predicted values of the elastic constant using simplified micormechanics equation of the composite are verified with experimental result that matches and have shown the significant improvement in the in plane shear strength of the composite that will help to improve the delaimination of the composite.

Early diagnosis and efficient treatment are of paramount importance to fight cancers. Monitoring the foreign body response of a patient to treatment therapies also plays an important role in improving the care that cancer patients receive... more

Early diagnosis and efficient treatment are of paramount importance to fight cancers. Monitoring the foreign body response of a patient to treatment therapies also plays an important role in improving the care that cancer patients receive by their medical practitioners. As such, there is extensive research being conducted into ultrasensitive point-of-care detection systems and “smart” personalized anti-cancer drug delivery systems. Electrospun nanofibers have emerged as promising materials for the construction of nanoscale biosensors and therapeutic platforms due to their large surface areas, controllable surface conformation, good surface modification, complex pore structure, and high biocompatibility. Electrospun nanofibers are produced by electrospinning, which is a very powerful and economically viable method of synthesizing versatile and scalable assemblies from a wide array of raw materials. This review describes the theory of electrospinning, achievements, and problems currently faced in producing effective biosensors/drug delivery systems, in particular, for cancer diagnosis and treatment. Finally, insights into future prospects are discussed.

Em artigo de revisão anterior[1], o processo de eletrofiação foi discutido, incluindo suas bases teóricas e experimentais, e a obtenção de diferentes nanofibras de materiais poliméricos. Neste segundo artigo de revisão, são abordados os... more

Em artigo de revisão anterior[1], o processo de eletrofiação foi discutido, incluindo suas bases teóricas e experimentais, e a obtenção de diferentes nanofibras de materiais poliméricos. Neste segundo artigo de revisão, são abordados os aspectos relacionados à aplicação de materiais eletrofiados em diferentes áreas, como médica, agrícola, sensores, processamento de outros materiais, entre outras. São também discutidas as técnicas de caracterização utilizadas mais frequentemente nestes materiais, e suas potencialidades. Esta segunda revisão é complementar à anterior e segue, em seus aspectos gerais, a mesma terminologia.

The feasibility of preparing cellulose acetate/carbon black (CA/CB) composite nanofiber in one step through electrospinning process and investigating its potential oil absorbability and application for machine oil removal from aquatic... more

The feasibility of preparing cellulose acetate/carbon black (CA/CB) composite nanofiber in one step through electrospinning process and investigating its potential oil absorbability and application for machine oil removal from aquatic environment was reported. Different CA/CB composite nanofibers were fabricated by electrospinning of cellulose acetate (CA) solution containing different loads of 0.7, 1.5, and 2.2% CB relative to the weight of CA and labeled as CA/CB0.7, CA/CB1.5, and CA/CB2.2. The scanning electron microscope (SEM) images showed continuous and smooth fiber with submicron diameter ranging from 400–900 nm with good adhering of CB into CA nanofiber. Furthermore, the CA/CB composite nanofibers exhibited high surface area compared with CA nanofiber, which reached 3.057, 2.8718 and 8.244 m2/g for CA/CB0.7, CA/CB1.5 and CA/CB2.2, respectively. Oil adsorption tests were performed with heavy and light machine oils. The CA/CB composite nanofibers showed higher affinity for oil...

Any significant loss of vision or blindness caused by corneal damages is referred to as corneal blindness. Corneal blindness is the fourth most common cause of blindness worldwide, representing more than 5% of the total blind population.... more

Any significant loss of vision or blindness caused by corneal damages is referred to as corneal blindness. Corneal blindness is the fourth most common cause of blindness worldwide, representing more than 5% of the total blind population. Currently, corneal transplantation is used to treat many corneal diseases. In some cases, implantation of artificial cornea (keratoprosthesis) is suggested after a patient has had a donor corneal transplant failure. The shortage of donors and the side effects of keratoprosthesis are limiting these approaches. Recently, researchers have been actively pursuing new approaches for corneal regeneration because of these limitations. Nowadays, tissue engineering of different corneal layers (epithelium, stroma, endothelium, or full thickness tissue) is a promising approach that has attracted a great deal of interest from researchers and focuses on regenerative strategies using different cell sources and biomaterials. Various sources of corneal and non-corneal stem cells have shown significant advantages for corneal epithelium regeneration applications. Pluripotent stem cells (embryonic stem cells and iPS cells), epithelial stem cells (derived from oral mucus, amniotic membrane, epidermis and hair follicle), mesenchymal stem cells (bone marrow, adipose-derived, amniotic membrane, placenta, umbilical cord), and neural crest origin stem cells (dental pulp stem cells) are the most promising sources in this regard. These cells could also be used in combination with natural or synthetic scaffolds to improve the efficacy of the therapeutic approach. As the ocular surface is exposed to external damage, the number of studies on regeneration of the corneal epithelium is rising. In this paper, we reviewed the stem cell-based strategies for corneal epithelium regeneration.