Search results for: electrospun

Authors: MyungGu Yeo, JongHan Ha, Gi-Hoon Yang, JaeYoon Lee, SeungHyun Ahn, Hyeongjin Lee, HoJun Jeon, YongBok Kim, Minseong Kim, GeunHyung Kim

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Tissue engineering is a rapidly growing interdisciplinary research area that may provide options for treating damaged tissues and organs. As a promising technique for regenerating various tissues, this technology requires biomedical scaffolds, which serve as an artificial extracellular matrix (ECM) to support neotissue growth. Electrospun micro/nanofibers have been used widely in tissue engineering because of their high surface-area-to-volume ratio and structural similarity to extracellular matrix. However, low mechanical sustainability, low 3D shape-ability, and low cell infiltration have been major limitations to their use. In this work, we propose new hybrid scaffolds interlayered with cell-laden electrospun micro/nano fibers and poly(caprolactone) microstructures. Also, we applied various concentrations of alginate and electric field strengths to determine optimal conditions for the cell-electrospinning process. The combination of cell-laden bioink (2 ⅹ 10^5 osteoblast-like MG63 cells/mL, 2 wt% alginate, 2 wt% poly(ethylene oxide), and 0.7 wt% lecithin) and a 0.16 kV/mm electric field showed the highest cell viability and fiber formation in this process. Using these conditions and PCL microstructures, we achieved mechanically stable hybrid scaffolds. In addition, the cells embedded in the fibrous structure were viable and proliferated. We suggest that the cell-embedded hybrid scaffolds fabricated using the cell-electrospinning process may be useful for various soft- and hard-tissue regeneration applications.

Keywords: bioink, cell-laden scaffold, micro/nanofibers, poly(caprolactone)

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Authors: Zeynep R. Ege, Aydin Akan, Faik N. Oktar, Betul Karademir, Oguzhan Gunduz

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Early detection of cancer could save human life and quality in insidious cases by advanced biomedical imaging techniques. Designing targeted detection system is necessary in order to protect of healthy cells. Electrospun nanofibers are efficient and targetable nanocarriers which have important properties such as nanometric diameter, mechanical properties, elasticity, porosity and surface area to volume ratio. In the present study, indocyanine green (ICG) organic dye was stabilized and encapsulated in polymer matrix which polyethylene oxide (PEO) and chitosan (CHI) multilayer nanofibers via co-axial electrospinning method at one step. The co-axial electrospun nanofibers were characterized as morphological (SEM), molecular (FT-IR), and entrapment efficiency of Indocyanine Green (ICG) (confocal imaging). Controlled release profile of PEO/CHI/ICG nanofiber was also evaluated up to 40 hours.

Keywords: chitosan, coaxial electrospinning, controlled releasing, drug delivery, indocyanine green, polyethylene oxide

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Authors: Ziwei Wang, Andrea Lucotti, Luigi Brambilla, Matteo Tommasini, Chiara Bertarelli

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Surface-enhanced Raman Spectroscopy (SERS) is a highly sensitive detection that provides abundant information on low concentration analytes from various researching areas. Based on localized surface plasmon resonance, metal nanostructures including gold, silver and copper have been investigated as SERS substrate during recent decades. There has been increasing more attention of exploring good performance, homogenous, repeatable SERS substrates. Here, we show that electrospinning, which is an inexpensive technique to fabricate large-scale, self-standing and repeatable membranes, can be effectively used for producing SERS substrates. Nanoparticles and nanorods are added to the feed electrospinning solution to collect functionalized polymer fibrous mats. We report stable electrospun membranes as SERS substrate using gold nanorods (AuNRs) and poly(vinyl alcohol). Particularly, a post-processing crosslinking step using glutaraldehyde under acetone environment was carried out to the electrospun membrane. It allows for using the membrane in any liquid environment, including water, which is of interest both for sensing of contaminant in wastewater, as well as for biosensing. This crosslinked AuNRs/PVA membrane has demonstrated excellent performance as SERS substrate for low concentration 10-6 M Rhodamine 6G (Rh6G) aqueous solution. This post-processing for fabricating SERS substrate is the first time reported and proved through Raman imaging of excellent stability and outstanding performance. Finally, SERS tests have been applied to several analytes, and the application of AuNRs/PVA membrane is broadened by removing the detected analyte by rinsing. Therefore, this crosslinked AuNRs/PVA membrane is re-usable.

Keywords: SERS spectroscopy, electrospinning, crosslinking, composite materials

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Authors: Z. Karahaliloğlu, C. Hacker, M. Demirbilek, G. Seide, E. B. Denkbaş, T. Gries

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Currently, textile industry has played an important role in world’s economy, especially in developing countries. Dyes and pigments used in textile industry are significant pollutants. Most of theirs are azo dyes that have chromophore (-N=N-) in their structure. There are many methods for removal of the dyes from wastewater such as chemical coagulation, flocculation, precipitation and ozonation. But these methods have numerous disadvantages and alternative methods are needed for wastewater decolorization. Titanium-mediated photodegradation has been used generally due to non-toxic, insoluble, inexpensive, and highly reactive properties of titanium dioxide semiconductor (TiO2). Melt electrospinning is an attractive manufacturing process for thin fiber production through electrospinning from PP (Polyprophylene). PP fibers have been widely used in the filtration due to theirs unique properties such as hydrophobicity, good mechanical strength, chemical resistance and low-cost production. In this study, we aimed to investigate the effect of titanium nanoparticle localization and amine modification on the dye degradation. The applicability of the prepared chemical activated composite and pristine fabrics for a novel treatment of dyeing wastewater were evaluated.In this study, a photocatalyzer material was prepared from nTi (titanium dioxide nanoparticles) and PP by a melt-electrospinning technique. The electrospinning parameters of pristine PP and PP/nTi nanocomposite fabrics were optimized. Before functionalization with nTi, the surface of fabrics was activated by a technique using glutaraldehyde (GA) and polyethyleneimine to promote the dye degredation. Pristine PP and PP/nTi nanocomposite melt-electrospun fabrics were characterized using scanning electron microscopy (SEM) and X-Ray Photon Spectroscopy (XPS). Methyl orange (MO) was used as a model compound for the decolorization experiments. Photocatalytic performance of nTi-loaded pristine and nanocomposite melt-electrospun filters was investigated by varying initial dye concentration 10, 20, 40 mg/L). nTi-PP composite fabrics were successfully processed into a uniform, fibrous network of beadless fibers with diameters of 800±0.4 nm. The process parameters were determined as a voltage of 30 kV, a working distance of 5 cm, a temperature of the thermocouple and hotcoil of 260–300 ºC and a flow rate of 0.07 mL/h. SEM results indicated that TiO2 nanoparticles were deposited uniformly on the nanofibers and XPS results confirmed the presence of titanium nanoparticles and generation of amine groups after modification. According to photocatalytic decolarization test results, nTi-loaded GA-treated pristine or nTi-PP nanocomposite fabric filtern have superior properties, especially over 90% decolorization efficiency at GA-treated pristine and nTi-PP composite PP fabrics. In this work, as a photocatalyzer for wastewater treatment, surface functionalized with nTi melt-electrospun fabrics from PP were prepared. Results showed melt-electrospun nTi-loaded GA-tretaed composite or pristine PP fabrics have a great potential for use as a photocatalytic filter to decolorization of wastewater and thus, requires further investigation.

Keywords: titanium oxide nanoparticles, polyprophylene, melt-electrospinning

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Authors: Mahsa Kangazian Kangazi, Ali Akbar Ghareh Aghaji, Majid Montazer

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Nowadays, silica nanofibers are highly regarded among the inorganic nanofibers due to the high reactivity and availability of silicon compounds in nature. Sol-gel process is required for electrospinning of silica nanofibers in which a metal alkoxide is hydrolyzed, and the viscosity is increased. In this study, silica nanofibers containing silver nanoparticles were synthesized and electrospun from a mixture of silica sol with an easy spinnable polymer (PVA) as an additive. The silica sol contains tetraethyl orthosilicate (TEOS), silver nitrate, distilled water, nitric acid, and ethanol. Nanofibers were formed through electrospinning setup. The nanofibers were calcinated to remove the solvent and additive polymer. Consequently, pure silica nanofibers were produced. FTIR analysis indicated entire removal of polyvinyl alcohol from the structure and formation of silan groups. The presence of silver, silica and oxygen was confirmed by EDX. Also, XRD patterns revealed the presence of silver nanoparticles with a mean crystal size of 18 nm. FESEM images showed that adding silver nitrate into the sol-gel, resulted in lower nanofibers diameter from 286 to 136 nm. Furthermore, the electrospun nanofibers were more resistance in acidic media than alkaline media.

Keywords: in situ synthesis of silver nanoparticles, silica nanofibers, sol-gel, tetraethyl orthosilicate

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Authors: Khryslyn Araño, Dela Cruz, Michael Leo, Dela Pena, Eden May, Leslie Joy Diaz

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Montmorillonite (MMT) is a very abundant clay mineral and is versatile such that it can be chemically or physically altered by changing the ions between the sheets of its layered structure. This clay mineral can be prepared into functional nanoparticles that can be used as fillers in other nanomaterials such as nanofibers to achieve special properties. In this study, two types of iron-modified MMT, Iron-MMT (FeMMT) and Zero Valent Iron-MMT (ZVIMMT) were synthesized via ion exchange technique. The modified clay was incorporated in polymer nanofibers which were produced using a process called electrospinning. ICP analysis confirmed that clay modification was successful where there is an observed decrease in the concentration of Na and an increase in the concentration of Fe after ion exchange. XRD analysis also confirmed that modification took place because of the changes in the d-spacing of Na-MMT from 11.5 Å to 13.6 Å and 12.6 Å after synthesis of FeMMT and ZVIMMT, respectively. SEM images of the electrospun nanofibers revealed that the ZVIMMT-filled fibers have a smaller average diameter than the FeMMT-filled fibers because of the lower resistance of the suspensions of the former to the elongation force from the applied electric field. The resistance to the electric field was measured by getting the bulk voltage of the suspensions.

Keywords: electrospinning, nanofibers, montmorillonite, materials science

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Authors: Ji Un Shin, Wei Mao, Hyuk Sang Yoo

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Electrospinning is a versatile tool for fabricating nano-structured polymeric materials. Gelatin hydrogels are considered to be a good material for cell cultivation because of high water swellability as well as good biocompatibility. Three-dimensional (3-D) cell cultivation is a desirable method of cell cultivation for preparing tissues and organs because cell-to-cell interactions or cell-to-matrix interactions can be much enhanced through this approach. For this reason, hydrogels were widely employed as tissue scaffolds because they can support cultivating cells and tissue in multi-dimensions. Major disadvantages of hydrogel-based cell cultivation include low mechanical properties, lack of topography, which should be enhanced for successful tissue engineering. Herein we surface-immobilized gelatin on the surface of nanofibrous matrix for 3-D cell cultivation in topographical cues added environments. Electrospun nanofibers were electrospun with injection of poly(caprolactone) through a single nozzle syringe. Electrospun meshes were then chopped up with a high speed grinder to fine powders. This was hydrolyzed in optimized concentration of sodium hydroxide solution from 1 to 6 hours and harvested by centrifugation. The freeze-dried powders were examined by scanning electron microscopy (SEM) for revealing the morphology and fibrilar shaped with a length of ca. 20um was observed. This was subsequently immersed in gelatin solution for surface-coating of gelatin, where the process repeated up to 10 times for obtaining desirable coating of gelatin on the surface. Gelatin-coated nanofibrils showed high waterswellability in comparison to the unmodified nanofibrils, and this enabled good dispersion properties of the modified nanofibrils in aqueous phase. The degree of water-swellability was increased as the coating numbers of gelatin increased, however, it did not any meaning result after 10 times of gelatin coating process. Thus, by adjusting the gelatin coating times, we could successfully control the degree of hydrophilicity and water-swellability of nanofibrils.

Keywords: nano, fiber, cell, tissue

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Authors: Sena Su, Burak Ozbek, Yesim M. Sahin, Sevil Yucel, Dilek Kazan, Faik N. Oktar, Nazmi Ekren, Oguzhan Gunduz

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In recent years, protein, lipid or polysaccharide-based polymers have been used in order to develop biodegradable materials and their chemical nature determines the physical properties of the resulting films. Among these polymers, proteins from different sources have been extensively employed because of their relative abundance, film forming ability, and nutritional qualities. In this study, the biodegradable composite nanofiber films based on fish sarcoplasmic protein (FSP) were prepared via electrospinning technique. Biodegradable polycaprolactone (PCL) was blended with the FSP to obtain hybrid FSP/PCL nanofiber mats with desirable physical properties. Mixture solutions of FSP and PCL were produced at different concentrations and their density, viscosity, electrical conductivity and surface tension were measured. Mechanical properties of electrospun nanofibers were evaluated. Morphology of composite nanofibers was observed using scanning electron microscopy (SEM). Moreover, Fourier transform infrared spectrometer (FTIR) studies were used for analysis chemical composition of composite nanofibers. This study revealed that the FSP based nanofibers have the potential to be used for different applications such as biodegradable packaging, drug delivery, and wound dressing, etc.

Keywords: edible film, electrospinning, fish sarcoplasmic protein, nanofiber

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Authors: Hilal Turkoglu Sasmazel, Ozan Ozkan, Seda Surucu

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Tissue engineering is the field of treating defects caused by injuries, trauma or acute/chronic diseases by using artificial scaffolds that mimic the extracellular matrix (ECM), the natural biological support for the tissues and cells within the body. The main aspects of a successful artificial scaffold are (i) large surface area in order to provide multiple anchorage points for cells to attach, (ii) suitable porosity in order to achieve 3 dimensional growth of the cells within the scaffold as well as proper transport of nutrition, biosignals and waste and (iii) physical, chemical and biological compatibility of the material in order to obtain viability throughout the healing process. By hybrid scaffolds where two or more different materials were combined with advanced fabrication techniques into complex structures, it is possible to combine the advantages of individual materials into one single structure while eliminating the disadvantages of each. Adding this to the complex structure provided by advanced fabrication techniques enables obtaining the desired aspects of a successful artificial tissue scaffold. In this study, fibroblast compatibility of poly(ε-caprolactone) (PCL)/chitosan core-shell electrospun hybrid scaffolds with proper mechanical, chemical and physical properties successfully developed in our previous study was investigated. Standard 7-day cell culture was carried out with L929 fibroblast cell line. The viability of the cells cultured with the scaffolds was monitored with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) viability assay for every 48 h starting with 24 h after the initial seeding. In this assay, blank commercial tissue culture polystyrene (TCPS) Petri dishes, single electrospun PCL and single electrospun chitosan mats were used as control in order to compare and contrast the performance of the hybrid scaffolds. The adhesion, proliferation, spread and growth of the cells on/within the scaffolds were observed visually on the 3rd and the 7th days of the culture period with confocal laser scanning microscopy (CSLM) and scanning electron microscopy (SEM). The viability assay showed that the hybrid scaffolds caused no toxicity for fibroblast cells and provided a steady increase in cell viability, effectively doubling the cell density for every 48 h for the course of 7 days, as compared to TCPS, single electrospun PCL or chitosan mats. The cell viability on the hybrid scaffold was ~2 fold better compared to TCPS because of its 3D ECM-like structure compared to 2D flat surface of commercially cell compatible TCPS, and the performance was ~2 fold and ~10 fold better compared to single PCL and single chitosan mats, respectively, even though both fabricated similarly with electrospinning as non-woven fibrous structures, because single PCL and chitosan mats were either too hydrophobic or too hydrophilic to maintain cell attachment points. The viability results were verified with visual images obtained with CSLM and SEM, in which cells found to achieve characteristic spindle-like fibroblast shape and spread on the surface as well within the pores successfully at high densities.

Keywords: chitosan, core-shell, fibroblast, electrospinning, PCL

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Authors: Hussein M. Etmimi, Peter E. Mallon

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Electrospinning uses an electrical charge to draw very fine fibers (typically on the micro or nano scale) from a liquid or molten precursor. Over the years, this method has become a widely used and a successful technique to process polymer materials and their composites into nanofibers. The main focus of this work is to study the electrospinning of multi-phase amphiphilic copolymers and their nanocomposites, which contain graphene as the nanofiller material. In such amphiphilic materials, the constituents segments are incompatible and thus the solid state morphology will be determined by the composition of the various constituents as well as the method of preparation. In this study, amphiphilic block copolymers of poly(dimethyl siloxane) and poly(methyl methacrylate) (PDMS-b-PMMA) with well-defined structures were synthesized and the solution electrospinning of these materials and their properties were investigated. Atom transfer radical polymerization (ATRP) was used to obtain the controlled block copolymers with relatively high molar masses and narrow dispersity. First, PDMS macroinitiators with different chain length of 1000, 5000 and 10000 g/mol were synthesized by the reaction of monocarbinol terminated PDMS with α-bromoisobutyryl bromide initiator. The obtained macroinitiators were used for the polymerization of methyl methacrylate monomer to obtain the desired block copolymers using the ATRP process. Graphene oxide (GO) of different loading was then added to the copolymer solution and the resultant nanocomposites were successfully electrospun into nanofibers. The electrospinning was achieved using dimethylformamide/chloroform mixture (60:40 vl%) as electrospinning solution medium. Scanning electron microscopy (SEM) showed the successful formation of the electrospun fibers with dimensions in the nanometer range. X-ray diffraction indicated that the GO nanosheets were of an exfoliated structure, irrespective of the filler loading. Thermogravimetric analysis also showed that the thermal stability of the nanofibers was improved in the presence of GO, which was not a function of the filler loading. Differential scanning calorimetry also showed that the mechanical properties (measured as glass transition temperature) of the nanofibers was improved significantly in the presence of GO, which was a function of the filler loading.

Keywords: elctrospinning, graphene oxide, nanofibers, polymethyl methacrylate (PMMA)

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Authors: Umran Kurtan, Hamide Aydin, Sevim Unugur Celik, Ayhan Bozkurt

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In the present work, novel hBN/polyacrylonitrile composite nanofibers were produced via electrospinning approach and loaded with the electrolyte for rechargeable lithium-ion battery applications. The electrospun nanofibers comprising various hBN contents were characterized by using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The influence of hBN/PAN ratios onto the properties of the porous composite system, such as fiber diameter, porosity, and the liquid electrolyte uptake capability were systematically studied. Ionic conductivities and electrochemical characterizations were evaluated after loading electrospun hBN/PAN composite nanofiber with liquid electrolyte, i.e., 1 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate (EC)/ethyl methyl carbonate (EMC) (1:1 vol). The electrolyte loaded nanofiber has a highest ionic conductivity of 10−3 S cm⁻¹ at room temperature. According to cyclic voltammetry (CV) results it exhibited a high electrochemical stability window up to 4.7 V versus Li+/Li. Li//10 wt% hBN/PAN//LiCO₂ cell was produced which delivered high discharge capacity of 144 mAhg⁻¹ and capacity retention of 92.4%. Considering high safety and low cost properties of the resulting hBN/PAN fiber electrolytes, these materials can be suggested as potential separator materials for lithium-ion batteries.

Keywords: hexagonal boron nitride, polyacrylonitrile, electrospinning, lithium ion battery

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Authors: Urszula Stachewicz

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Surface properties of materials are the key parameter in many applications, especially in the biomedical field, to control cell-material interactions. In our work, we want to achieve the controllability of surface properties of polymer fibers via a single-step electrospinning process by alternating voltage polarities. Voltage polarity defines the charge accumulated on the surface of the liquid jet and the surface of the fibers. Positive polarity attracts negatively charged groups to fibers’ surface, whereas negative polarity moves the negatively charged functional groups away from the surface. This way, we can control the surface chemistry, wettability, and additionally surface potential of electrospun fibers. Within our research, we characterized surface chemistry using X-ray photoelectron microscopy (XPS) and surface potential with Kelvin probe force microscopy (KPFM) on electrospun fibers of commonly used polymers such as PCL, PVDF, and PMMA, often used as biomaterials. We proved the significant effect of fibers' surface potential on cell integration with the scaffolds and further cells development for the regeneration processes based on the osteoblast and fibroblast culture studies. Acknowledgments: The study was conducted within ‘Nanofiber-based sponges for atopic skin treatment’ project, which is carried out within the First TEAM programme of the Foundation for Polish Science co-financed by the European Union under the European Regional Development Fund, project no POIR.04.04.00-00- 4571/18-00.

Keywords: cell attachment, fibers, fibroblasts, osteoblast, proliferation, surface potential

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Authors: B. Kodedova, E. Filova, M. Kralovic, E. Amler

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Vitiligo is the most common depigmentation disorder of the skin characterized by loss of melanocyte in the epidermis that leads to white lesions. One of the possible treatments is autologous transplantation of melanocytes. Biodegradable electrospun polymeric nanofibers provide good mechanical properties and could serve as suitable scaffold for epithelial cells cultivation and follow up transplantation. Moreover the microarchitecture of nanofibers mimics the structure of extracellular matrix and its porosity allows nutrients and waste exchange. The aim of this work was to develop biocompatible and biodegradable polymeric scaffolds suitable for autologous melanocytes transplantation. Electrospun polyvinyl alcohol (PVA) nanofibers were modified by cold methane plasma to lower their hydrofility and to achieve better adhesion, proliferation and viability of the murine melanocyte (Melan-a). Cells were seeded on the modified scaffolds and their adhesion, metabolic activity, proliferation and melanin synthesis was evaluated and compared to non-modified scaffolds. Results clearly indicate that cold methane plasma modified PVA nanofibers are suitable for melanocyte cultivation and may be future candidate for vitiligo treatment. Furthermore, the nanofibers can be functionalized with various bioactive substances, for enhancement of the melanocyte proliferation, melanogenesis or healing and regenerative processes. The project was supported by the Ministry of Education, Youth and Sports NPU I: LO1309 and by Grant Agency of Charles University (grant No. 1228214).

Keywords: melanocyte, nanofibers, polyvinyl alcohol, plasma modification

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Authors: Mohamed H. El-Newehy, Badr M. Thamer, Nasser A. M. Barakat, Mohammad A.Abdelkareem, Salem S. Al-Deyab, Hak Y. Kim

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In this study, the influence of nitrogen doping on the electrocatalytic activity of carbon nanofibers with nickel nanoparticles toward methanol oxidation is introduced. The modified carbon nanofibers have been synthesized from calcination of electrospun nanofiber mats composed of nickel acetate tetrahydrate, poly(vinyl alcohol) and urea in argon atmosphere at 750oC. The utilized physicochemical characterizations indicated that the proposed strategy leads to form carbon nanofibers having nickel nanoparticles and doped by nitrogen. Moreover, due to the high-applied voltage during the electrospinning process, the utilized urea chemically bonds with the polymer matrix, which leads to form nitrogen-doped CNFs after the calcination process. Investigation of the electrocatalytic activity indicated that nitrogen doping NiCNFs strongly enhances the oxidation process of methanol as the current density increases from 52.5 to 198.5 mA/cm2 when the urea content in the original electrospun solution was 4 wt% urea. Moreover, the nanofibrous morphology exhibits distinct impact on the electrocatalytic activity. Also, nitrogen-doping enhanced the stability of the introduced Ni-based electrocatalyst. Overall, the present study introduces effective and simple strategy to modify the electrocatalytic activity of the nickel-based materials.

Keywords: electrospinning, methanol electrooxidation, fuel cells, nitrogen-doping, nickel

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Authors: Badr M. Thamer

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The use of hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-g-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by in-situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including the ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on the adsorption process were explored. The adsorption isotherm and kinetic were studied by numerous non-linear models. The obtained results confirmed that the incorporation of O-ECNFs into the hydrogel network improved its ability towards MB dye removal with decreasing their swelling capacity. The adsorption process depends on the pH value of the dye solution. Additionally, the adsorption and kinetic results were fitted using the Freundlich isotherm model and pseudo second order model (PSO), respectively. Moreover, the new adsorbents can be recycled for at least five cycles keeping its adsorption capacity and can be easily recovered without loss in its initial weight.

Keywords: carbon nanofibers, hydrogels, nanocomposites, water treatment

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Authors: Seon Yeong Byeon, Hwa Sung Shin

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Nanofibrous sheets are of interest in the beauty industries due to the properties of moisturizing, adhesion to skin and delivery of nutrient materials. The benefit and function of the cosmetic products should not be considered without safety thus a non-toxic manufacturing process is ideal when fabricating the products. In this study, we have developed cosmetic patches consisting of alginate and Spirulina extract, a marine resource which has antibacterial and antioxidant effects, without addition of harmful cross-linkers. The patches obtained their structural stabilities by layer-upon-layer electrospinning of an alginate layer on a formerly spread polycaprolactone (PCL) layer instead of crosslinking method. The morphological characteristics, release of Spirulina extract, water absorption, skin adhesiveness and cytotoxicity of the double-layered patches were assessed. The image of scanning electron microscopy (SEM) showed that the addition of Spirulina extract has made the fiber diameter of alginate layers thinner. Impregnation of Spirulina extract increased their hydrophilicity, moisture absorption ability and skin adhesive ability. In addition, wetting the pre-dried patches resulted in releasing the Spirulina extract within 30 min. The patches were detected to have no cytotoxicity in the human keratinocyte cell-based MTT assay, but rather showed increased cell viability. All the results indicate the bioactive and hydro-adhesive double-layered patches have an excellent applicability to bioproducts for personal skin care in the trend of ‘A mask pack a day’.

Keywords: alginate, cosmetic patch, electrospun nanofiber, polycaprolactone, Spirulina extract

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Authors: Daniel Canales, Fabián Alvarez, Pablo Varela, Marcela Saavedra, Claudio García, Paula Zapata

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Calcium oxide nanoparticles (n-CaO) ca. 8 nm were obtained from eggshell waste. The n-CaO was incorporated into Poly(lactic acid) PLA matrix in 10 and 20 wt.% of filler content by electrospinning process to obtain PLA/n-CaO nanocomposite fibers as a potential use in scaffold for bone tissue regeneration. The fibers morphology and diameter were homogeneity, the PLA had a diameter of 2.2 ± 0.8 µm and, with the nanoparticles incorporation (20wt.%), reached ca. 2.9 ± 0.9 µm. The PLA/n-CaO nanocomposites fibers showed in vitro bioactivity, capable of inducing the precipitation of hydroxyapatite (HA) layer in the fiber surface after 7 days in Simulated Body Solution (SBF). The biocidal and biological properties of PLA/n-Cao with 20 wt.% were evaluated, showing a 30% reduction in bacterial viability against S. aureus and 11% for E. coli after 6 hours of bacterial suspensions exposure. Furthermore, the fibers did not show a cytotoxic effect on the bone marrow ST-2 cell line, permitting the cell adhesion and proliferation in Roswell Park Memorial Institute medium (RPMI). The PLA/n-CaO with 20 wt.% of nanoparticles showed a higher capacity to promote the osteogenic differentiation, significantly increasing the alkaline phosphatase (ALP) expression after 7 days compared to PLA and cell control. The in vivo analysis corroborated the biocompatibility of scaffolds prepared, the presence of n-CaO in PLA reduced the formation of fibrous encapsulation of the material improve the healing process.

Keywords: electrospun scaffolds, PLA based nanocomposites, calcium oxide nanoparticles, bioactive materials, tissue engineering

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Authors: Zubair Khaliq, M. Bilal Qadir, Amir Shahzad, Zulfiqar Ali, Ahsan Nazir, Ali Afzal, Abdul Jabbar

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Carbon fibers are one of the most demanding materials on earth due to their potential application in energy, high strength materials, and conductive materials. The nanostructure of carbon fibers offers enhanced properties of conductivity due to the larger surface area. The next generation carbon nanofibers demand the porous structure as it offers more surface area. Multiple techniques are used to produce carbon fibers. However, electrospinning followed by carbonization of the polymeric materials is easy to carry process on a laboratory scale. Also, it offers multiple diversity of changing parameters to acquire the desired properties of carbon fibers. Polyacrylonitrile (PAN) is the most used material for the production of carbon fibers due to its promising processing parameters. Also, cellulose is one of the highest yield producers of carbon fibers. However, the electrospinning of cellulosic materials is difficult due to its rigid chain structure. The combination of PAN and cellulose can offer a suitable solution for the production of carbon fibers. Both materials are miscible in the mixed solvent of N, N, Dimethylacetamide and lithium chloride. This study focuses on the production of porous carbon fibers as a function of PAN/Cellulose blend ratio, solution properties, and electrospinning parameters. These single polymer and blend with different ratios were electrospun to give fine fibers. The higher amount of cellulose offered more difficulty in electrospinning of nanofibers. After carbonization, the carbon fibers were studied in terms of their blend ratio, surface area, and texture. Cellulose contents offered the porous structure of carbon fibers. Also, the presence of LiCl contributed to the porous structure of carbon fibers.

Keywords: cellulose, polyacrylonitrile, carbon nanofibers, electrospinning, blend

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Authors: Mauricio Gómez, Esmeralda López, Ian Becar, Jaime Pizarro, Paula A. Zapata

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A biodegradable material is developed with adsorptive capacity for metals ion for intended use in mining tailings mitigating the environmental impact with economic retribution, two types of fibers were elaborated by electrospinning: (1) a cellulose acetate (CA) matrix and (2) a cellulose acetate (CA)/chitosan (CH) matrix evaluating the effect of CH in CA on its physicochemical properties. Through diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) the incorporation of chitosan in the matrix was identified, observing the band of the amino group at 1500 - 1600 [cm-1]. By scanning electron microscopy (SEM), Hg porosimetry, and CO2 isotherm at 273 [K], the intrafiber microporosity and interfiber macroporosity were identified, with an increase in the distribution of macropores for CA/CH fibers. In the tensile test, CH into the matrix produces a more ductile and tenacious behavior, where the % elongation at break increased by 33% with the other parameters constant. Thermal analysis by differential scanning calorimetry (DSC) and Thermogravimetric Analysis (TGA) showed that the incorporation of chitosan produces higher retention of water molecules due to the functional groups (amino groups (- NH3)), but there is a decrease in the specific heat and thermoplastic properties of the matrix since the glass transition temperature and softening temperature disappear. The effect of the optimum pH for CA and CA/CH fibers were studied in a batch system. In the adsorption kinetic study, the best isotherm model adapted to the experimental results corresponds to the Sips model and the kinetics corresponds to pseudo-second order

Keywords: environmental materials, wastewater treatment, electrospun fibers, biopolymers (cellulose acetate/chitosan), metals recovery

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Authors: Piotr K. Szewczyk, Arkadiusz Gradys, Sungkyun Kim, Luana Persano, Mateusz M. Marzec, Oleksander Kryshtal, Andrzej Bernasik, Sohini Kar-Narayan, Pawel Sajkiewicz, Urszula Stachewicz

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Piezoelectric polymers have received great attention in smart textiles, wearables, and flexible electronics. Their potential applications range from devices that could operate without traditional power sources, through self-powering sensors, up to implantable biosensors. Semi-crystalline PVDF is often proposed as the main candidate for industrial-scale applications as it exhibits exceptional energy harvesting efficiency compared to other polymers combined with high mechanical strength and thermal stability. Plenty of approaches have been proposed for obtaining PVDF rich in the desired β-phase with electric polling, thermal annealing, and mechanical stretching being the most prevalent. Electrospinning is a highly tunable technique that provides a one-step process of obtaining highly piezoelectric PVDF fibers without the need for post-treatment. In this study, voltage polarity and relative humidity influence on electrospun PVDF, fibers were investigated with the main focus on piezoelectric β-phase contents and piezoelectric performance. Morphology and internal structure of fibers were investigated using scanning (SEM) and transmission electron microscopy techniques (TEM). Fourier Transform Infrared Spectroscopy (FITR), wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) were used to characterize the phase composition of electrospun PVDF. Additionally, surface chemistry was verified with X-ray photoelectron spectroscopy (XPS). Piezoelectric performance of individual electrospun PVDF fibers was measured using piezoresponse force microscopy (PFM), and the power output from meshes was analyzed via custom-built equipment. To prepare the solution for electrospinning, PVDF pellets were dissolved in dimethylacetamide and acetone solution in a 1:1 ratio to achieve a 24% solution. Fibers were electrospun with a constant voltage of +/-15kV applied to the stainless steel nozzle with the inner diameter of 0.8mm. The flow rate was kept constant at 6mlh⁻¹. The electrospinning of PVDF was performed at T = 25°C and relative humidity of 30 and 60% for PVDF30+/- and PVDF60+/- samples respectively in the environmental chamber. The SEM and TEM analysis of fibers produced at a lower relative humidity of 30% (PVDF30+/-) showed a smooth surface in opposition to fibers obtained at 60% relative humidity (PVDF60+/-), which had wrinkled surface and additionally internal voids. XPS results confirmed lower fluorine content at the surface of PVDF- fibers obtained by electrospinning with negative voltage polarity comparing to the PVDF+ obtained with positive voltage polarity. Changes in surface composition measured with XPS were found to influence the piezoelectric performance of obtained fibers what was further confirmed by PFM as well as by custom-built fiber-based piezoelectric generator. For PVDF60+/- samples humidity led to an increase of β-phase contents in PVDF fibers as confirmed by FTIR, WAXS, and DSC measurements, which showed almost two times higher concentrations of β-phase. A combination of negative voltage polarity with high relative humidity led to fibers with the highest β-phase contents and the best piezoelectric performance of all investigated samples. This study outlines the possibility to produce electrospun PVDF fibers with tunable piezoelectric performance in a one-step electrospinning process by controlling relative humidity and voltage polarity conditions. Acknowledgment: This research was conducted within the funding from m the Sonata Bis 5 project granted by National Science Centre, No 2015/18/E/ST5/00230, and supported by the infrastructure at International Centre of Electron Microscopy for Materials Science (IC-EM) at AGH University of Science and Technology. The PFM measurements were supported by an STSM Grant from COST Action CA17107.

Keywords: crystallinity, electrospinning, PVDF, voltage polarity

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Authors: Aliaa M. S. Salem, Soliman I. El-Hout, Amira Gaber, Hassan Nageh

Abstract:

Nowadays, the development of poisonous gas detectors is considered to be an urgent matter to secure human health and the environment from poisonous gases, in view of the fact that even a minimal amount of poisonous gas can be fatal. Of these concerns, various inorganic or organic sensing materials have been used. Among these are conducting polymers, have been used as the active material in the gassensorsdue to their low-cost,easy-controllable molding, good electrochemical properties including facile fabrication process, inherent physical properties, biocompatibility, and optical properties. Moreover, conducting polymer-based chemical sensors have an amazing advantage compared to the conventional one as structural diversity, facile functionalization, room temperature operation, and easy fabrication. However, the low selectivity and conductivity of conducting polymers motivated the doping of it with varied materials, especially graphene, to enhance the gas-sensing performance under ambient conditions. There were a number of approaches proposed for producing polymer/ graphene nanocomposites, including template-free self-assembly, hard physical template-guided synthesis, chemical, electrochemical, and electrospinning...etc. In this work, we aim to prepare a novel gas sensordepending on Electrospun nanofibers of conducting polymer/RGO composite that is the effective and efficient expectation of poisonous gases like ammonia, in different application areas such as environmental gas analysis, chemical-,automotive- and medical industries. Moreover, our ultimate objective is to maximize the sensing performance of the prepared sensor and to check its recovery properties.

Keywords: electro spinning process, conducting polymer, polyaniline, polypyrrole, polythiophene, graphene oxide, reduced graphene oxide, functionalized reduced graphene oxide, spin coating technique, gas sensors

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Authors: Mahboubeh Kabiri, Saba Aslani

Abstract:

Among various approaches used for the treatment of cardiovascular diseases, the occlusion of the small-diameter vascular graft (SDVG) is still an unresolved problem which seeks further research to address them. Though autografts are now the gold standards to be replaced for blocked coronary arteries, they suffer from inadequate quality and quantity. On the other hand, the major problems of the tissue engineered grafts are thrombosis and intimal hyperplasia. Provision of a suitable spatiotemporal release pattern of anticoagulant agents such as heparin and aspirin can be a step forward to overcome such issues . Herein, we fabricated electrospun scaffolds from FDA (Food and Drug Administration) approved poly-L-lactic acid (PLLA) with aspirin loaded into the nanofibers. Also, we surface coated the scaffolds with Amniotic Membrane lysate as a source for natural elastic polymers and a mimic of endothelial basement membrane. The scaffolds were characterized thoroughly structurally and mechanically for their morphology, fiber orientation, tensile strength, hydrophilicity, cytotoxicity, aspirin release and cell attachment support. According to the scanning electron microscopy (SEM) images, the size of fibers ranged from 250 to 500 nm. The scaffolds showed appropriate tensile strength expected for vascular grafts. Cellular attachment, growth, and infiltration were proved using SEM and MTT (3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide) assay. Drug-loaded scaffolds showed a sustained release profile of aspirin in 7 days. An enhanced cytocompatibility was observed in AM-coated electrospun PLLA fibers compared to uncoated scaffolds. Our results together indicated that AM lysate coated ASA releasing scaffolds have promising potentials for development of a biocompatible SDVG.

Keywords: vascular tissue engineering, vascular grafts, anticoagulant agent, aspirin, amniotic membrane

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Authors: Matej Buzgo, Erico Himawan, Ksenija JašIna, Aiva Simaite

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Electrospinning is a versatile and efficient technology for producing nanofibers for biomedical applications. One of the most common polymers used for the preparation of nanofibers for regenerative medicine and drug delivery applications is polycaprolactone (PCL). PCL is a biocompatible and bioabsorbable material that can be used to stimulate the regeneration of various tissues. It is also a common material used for the development of drug delivery systems by blending the polymer with small active molecules. However, for many drug delivery applications, e.g. cancer immunotherapy, PCL biodegradation rate that may exceed 9 months is too long, and faster nanofiber dissolution is needed. In this paper, we investigate the dissolution and small molecule release rates of PCL blends with two hydrophilic polymers: polyethylene oxide (PEO) or polyvinylpyrrolidone (PVP). We show that adding hydrophilic polymer to the PCL reduces the water contact angle, increases the dissolution rate, and strengthens the interactions between the hydrophilic drug and polymer matrix that further sustain its release. Finally using this method, we were also able to increase the nanofiber degradation rate when PCL-PEO and PCL-PVP were used as a shell in the electrospun core-shell nanofibers and spread up the release of active proteins from their core. Electrospinning can be used for the preparation of the core-shell nanofibers, where active ingredients are encapsulated in the core and their release rate is regulated by the shell. However, such fibers are usually prepared by coaxial electrospinning that is an extremely low-throughput technique. An alternative is emulsion electrospinning that could be upscaled using needleless blades. In this work, we investigate the possibility of using emulsion electrospinning for encapsulation and sustained release of the growth factors for the development of the organotypic skin models. The core-shell nanofibers were prepared using the optimized formulation and the release rate of proteins from the fibers was investigated for 2 weeks – typical cell culture conditions.

Keywords: electrospinning, polycaprolactone (PCL), polyethylene oxide (PEO), polyvinylpyrrolidone (PVP)

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Authors: M. Grandcolas, N. Rival, H. Bu, S. Jahren, R. Schmid, H. Johnsen

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The concept of an autonomic self-healing material, where initiation of repair is integrated to the material, is now being considered for engineering applications and is a hot topic in the literature. Among several concepts/techniques, two are most interesting: i) Capsules: Integration of microcapsules in or at the surface of coatings or fibre-like structures has recently gained much attention. Upon damage-induced cracking, the microcapsules are broken by the propagating crack fronts resulting in a release of an active chemical (healing agent) by capillary action, subsequently repairing and avoiding further crack growth. ii) Self-healing polymers: Interestingly, the introduction of dynamic covalent bonds into polymer networks has also recently been used as a powerful approach towards the design of various intrinsically self-healing polymer systems. The idea behind this is to reconnect the chemical crosslinks which are broken when a material fractures, restoring the integrity of the material and thereby prolonging its lifetime. We propose here to integrate both self-healing concepts (capsules, self-healing polymers) in electrospun fibres and coatings. Different capsule preparation approaches have been investigated in SINTEF. The most advanced method to produce capsules is based on emulsification to create a water-in-oil emulsion before polymerisation. The healing agent is a polyurethane-based dispersion that was encapsulated in shell materials consisting of urea-benzaldehyde resins. Results showed the successful preparation of microcapsules and release of the agent when capsules break. Since capsules are produced in water-in-oil systems we mainly investigated organic solvent based coatings while a major challenge resides in the incorporation of capsules into water-based coatings. We also focused on developing more robust microcapsules to prevent premature rupture of the capsules. The capsules have been characterized in terms of size, and encapsulation and release might be visualized by incorporating fluorescent dyes and examine the capsules by microscopy techniques. Alternatively, electrospinning is an innovative technique that has attracted enormous attention due to unique properties of the produced nano-to-micro fibers, ease of fabrication and functionalization, and versatility in controlling parameters. Especially roll-to-roll electrospinning is a unique method which has been used in industry to produce nanofibers continuously. Electrospun nanofibers can usually reach a diameter down to 100 nm, depending on the polymer used, which is of interest for the concept with self-healing polymer systems. In this work, we proved the feasibility of fabrication of POSS-based (POSS: polyhedral oligomeric silsesquioxanes, tradename FunzioNano™) nanofibers via electrospinning. Two different formulations based on aqueous or organic solvents have shown nanofibres with a diameter between 200 – 450nm with low defects. The addition of FunzioNano™ in the polymer blend also showed enhanced properties in term of wettability, promising for e.g. membrane technology. The self-healing polymer systems developed are here POSS-based materials synthesized to develop dynamic soft brushes.

Keywords: capsules, coatings, electrospinning, fibers

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Authors: Sita Lakshmi Thyagarajan

Abstract:

Nanofibers will leave no field untouched by its scientific innovations; the medical field is no exception. Electrospinning has proven to be an excellent method for the synthesis of nanofibers which, have attracted the interest for many biomedical applications. The formation of biofilms in wounds often leads to chronic infections that are difficult to treat with antibiotics. In order to minimize the biofilms and enhance the wound healing, preparation of potential nanofibers was focused. In this study, siderophore incorporated nanofibers were electrospun using biocompatible polymers onto the collagen scaffold and were fabricated into a biomaterial suitable for the inhibition of biofilm formation. The purified microbial siderophore was blended with Poly-L-lactide (PLLA) and poly (ethylene oxide) PEO in a suitable solvent. Fabrication of siderophore blended nanofibers onto the collagen surface was done using standard protocols. The fabricated scaffold was subjected to physical-chemical characterization. The results indicated that the fabrication processing parameters of nanofiberous scaffold was found to possess the characteristics expected of the potential scaffold with nanoscale morphology and microscale arrangement. The influence of Poly-L-lactide (PLLA) and poly (ethylene oxide) PEO solution concentration, applied voltage, tip-to-collector distance, feeding rate, and collector speed were studied. The optimal parameters such as the ratio of Poly-L-lactide (PLLA) and poly (ethylene oxide) PEO concentration, applied voltage, tip-to-collector distance, feeding rate, collector speed were finalized based on the trial and error experiments. The fibers were found to have a uniform diameter with an aligned morphology. The overall study suggests that the prepared siderophore entrapped nanofibers could be used as a potent tool for wound dressing material for inhibition of biofilm formation.

Keywords: biofilms, electrospinning, nano-fibers, siderophore, tissue engineering scaffold

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Authors: Yasin Akgül, Yusuf Polat, Emine Canbay, Ali Kılıç

Abstract:

Wound dressings have strategically and economic importance considering increase of chronic wounds in the world. In this study, TPU nanofibrous membranes containing propolis as wound dressing are produced by two different methods. Firstly, TPU solution and propolis extract were mixed and this solution was electrospun. The other method is that TPU/propolis blend was centrifugally spun. Properties of nanofibrous membranes obtained by these methods were compared. While realizing the experiments, both systems were optimized to produce nanofibers with nearly same average fiber diameter.

Keywords: nanofiber, wound dressing, electrospinning, centrifugal spinning

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Authors: Zainab Dahrouch, Beatrix Petrovičová, Claudia Triolo, Fabiola Pantò, Angela Malara, Salvatore Patanè, Maria Allegrini, Saveria Santangelo

Abstract:

Synthetic dyes dispersed in water cause environmental damage and have harmful effects on human health. Methylene blue (MB) is broadly used as a dye in the textile, pharmaceutical, printing, cosmetics, leather, and food industries. The complete removal of MB is difficult due to the presence of aromatic rings in its structure. The present study is focused on electrospun nanofibers (NFs) with engineered architecture and surface to be used as catalysts for the photodegradation of MB. Ti and/or Zn oxide NFs are produced by electrospinning precursor solutions with different Ti: Zn molar ratios (from 0:1 to 1:0). Subsequent calcination and cooling steps are operated at fast rates to generate porous NFs with capture centers to reduce the recombination rate of the photogenerated charges. The comparative evaluation of the NFs as photocatalysts for the removal of MB from an aqueous solution with a dye concentration of 15 µM under UV irradiation shows that the binary (wurtzite ZnO and anatase TiO₂) oxides exhibit higher catalytic activity compared to ternary (ZnTiO₃ and Zn₂TiO₄) oxides. The higher band gap and lower crystallinity of the ternary oxides are responsible for their lower photocatalytic activity. It has been found that the optimal load for the wurtzite ZnO is 0.66 mg mL⁻¹, obtaining a degradation rate of 7.94.10⁻² min⁻¹. The optimal load for anatase TiO₂ is lower (0.33 mg mL⁻¹) and the corresponding rate constant (1.12×10⁻¹ min⁻¹) is higher. This finding (higher activity with lower load) is of crucial importance for the scaling up of the process on an industrial scale. Indeed, the anatase NFs outperform even the commonly used P25-TiO₂ benchmark. Besides, they can be reused twice without any regeneration treatment, with 5.2% and 18.7% activity decrease after second and third use, respectively. Thanks to the scalability of the electrospinning technique, this laboratory-scale study provides a perspective towards the sustainable large-scale manufacture of photocatalysts for the treatment of industry effluents.

Keywords: anatase, capture centers, methylene blue dye, nanofibers, photodegradation, zinc oxide

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Authors: Mahoud Alfama, Meloud Yones, Abdelbaset Zroga, Abdelati Elalem

Abstract:

Electrospinning has been recognized as an efficient technique for the fabrication of polymer nanofibers. Various polymers have been successfully electrospun into ultrafine fibers in recent years mostly in solvent solution and some in melt form. Potential applications based on such fibers specifically their use as reinforcement in nanocomposite development have been realized. In this paper we examine -electrospinning by providing a brief description of the theory behind the process examining the effect of changing the process parameters on fiber morphology, and discussing the potential applications and impacts of electrospinning on the field of tissue engineering.

Keywords: nanotechnology, electro spinning, reinforced materials

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Authors: Ariel Vilchez, Francisca Acevedo, Rodrigo Navia

Abstract:

The wound healing process can be accelerated and improved by the action of antioxidants such as curcumin (Cur) over the tissues; however, the efficacy of curcumin used through the digestive system is not enough to exploit its benefits. Electrospinning presents an alternative to carry curcumin directly to the wounds, and polyhydroxybutyrate (PHB) is proposed as the matrix to load curcumin owing to its biodegradable and biocompatible properties. PHB is among 150 types of Polyhydroxyalkanoates (PHAs) identified, it is a natural thermoplastic polyester produced by microbial fermentation obtained from microorganisms. The proposed objective is to develop electrospun bacterial PHB-based microfibers containing curcumin for possible biomedical applications. Commercial PHB was solved in Chloroform: Dimethylformamide (4:1) to a final concentration of 7% m/V. Curcumin was added to the polymeric solution at 1%, and 7% m/m regarding PHB. The electrospinning equipment (NEU-BM, China) with a rotary collector was used to obtain Cur-PHB fibers at different voltages and flow rate of the polymeric solution considering a distance of 20 cm from the needle to the collector. Scanning electron microscopy (SEM) was used to determine the diameter and morphology of the obtained fibers. Thermal stability was obtained from Thermogravimetric (TGA) analysis, and Fourier Transform Infrared Spectroscopy (FT-IR) was carried out in order to study the chemical bonds and interactions. A preliminary curcumin release to Phosphate Buffer Saline (PBS) pH = 7.4 was obtained in vitro and measured by spectrophotometry. PHB fibers presented an intact chemical composition regarding the original condition (dust) according to FTIR spectra, the diameter fluctuates between 0.761 ± 0.123 and 2.157 ± 0.882 μm, with different qualities according to their morphology. The best fibers in terms of quality and diameter resulted in sample 2 and sample 6, obtained at 0-10kV and 0.5 mL/hr, and 0-10kV and 1.5 mL/hr, respectively. The melting temperature resulted near 178 °C, according to the bibliography. The crystallinity of fibers decreases while curcumin concentration increases for the studied interval. The curcumin release reaches near 14% at 37 °C at 54h in PBS adjusted to a quasi-Fickian Diffusion. We conclude that it is possible to load curcumin in PHB to obtain continuous, homogeneous, and solvent-free microfibers by electrospinning. Between 0% and 7% of curcumin, the crystallinity of fibers decreases as the concentration of curcumin increases. Thus, curcumin enhances the flexibility of the obtained material. HPLC should be used in further analysis of curcumin release.

Keywords: antioxidant, curcumin, polyhydroxybutyrate, wound healing

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Authors: A. Dashti, M. Eskandari, L. Farahmand, P. Parvin, A. Jafargholi

Abstract:

Breast Cancer is one of the most considerable diseases in the United States and other countries and is the second leading cause of death in women. Common breast cancer treatments would lead to adverse side effects such as loss of hair, nausea, and weakness. These complications arise because these cancer treatments damage some healthy cells while eliminating the cancer cells. In an effort to address these complications, laser radiation was utilized and tested as a targeted cancer treatment for breast cancer. In this regard, tissue engineering approaches are being employed by using an electrospun scaffold in order to facilitate the growth of breast cancer cells. Polycaprolacton (PCL) was used as a material for scaffold fabricating because of its biocompatibility, biodegradability, and supporting cell growth. The specific breast cancer cells have the ability to create a three-dimensional cell cluster due to the spontaneous accumulation of cells in the porosity of the scaffold under some specific conditions. Therefore, we are looking for a higher density of porosity and larger pore size. Fibers showed uniform diameter distribution and final scaffold had optimum characteristics with approximately 40% porosity. The images were taken by SEM and the density and the size of the porosity were determined with the Image. After scaffold preparation, it has cross-linked by glutaraldehyde. Then, it has been washed with glycine and phosphate buffer saline (PBS), in order to neutralize the residual glutaraldehyde. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidefor (MTT) results have represented approximately 91.13% viability of the scaffolds for cancer cells. In order to create a cluster, Michigan Cancer Foundation-7 (MCF-7, breast cancer cell line) and Michigan Cancer Foundation-10A (MCF-10A, human mammary epithelial cell line) cells were cultured on the scaffold in 24 well plate for five days. Then, we have exposed the cluster to the laser diode 808 nm radiation to investigate the effect of laser on the tumor with different power and time. Under the same conditions, cancer cells lost their viability more than the healthy ones. In conclusion, laser therapy is a viable method to destroy the target cells and has a minimum effect on the healthy tissues and cells and it can improve the other method of cancer treatments limitations.

Keywords: breast cancer, electrospun scaffold, polycaprolacton, laser diode, cancer treatment

Procedia PDF Downloads 117