Five types of nanofibrous membranes were prepared by electrospinning poly(ε-caprolactone) (PCL), poly(D,L-lactide) (PDLLA), poly(lactide-co-caprolactone) (P(LA/CL)), poly(D,L-lactide-co-glycolide) (PDLGA) and methoxy polyethylene glycol-poly(lactide-co-glycolide) (MPEG-PLGA), respectively. These electrospun nanofibrous membranes (ENFMs) were used to adsorb anthracene (ANT), benz[a]anthracene (BaA) and benzo[a]pyrene (BaP) from aqueous solution, and the sorption kinetics and isotherms of these PAHs on the five ENFMs were investigated. The pseudo-second-order model (PSOM) can well describe the sorption kinetics of the three PAHs on five ENFMs, and the partition-adsorption model (PAM) can interpret the sorption processes of PAHs on the ENFMs. PCL ENFMs, which had the largest surface areas (8.57 m(2)g(-1)), exhibited excellent sorption capacity for ANT at over 4112.3 ± 35.5 μg g(-1). Moreover, the hydrophobicity and pore volume of ENFMs significantly affected the sorption kinetics and sorption capacity
TY - JOUR. T1 - Proliferation of genetically modified human cells on electrospun nanofiber scaffolds. AU - Borjigin, Mandula. AU - Strouse, Bryan. AU - Niamat, Rohina A.. AU - Bialk, Pawel. AU - Eskridge, Chris. AU - Xie, Jingwei. AU - Kmiec, Eric B.. PY - 2012. Y1 - 2012. N2 - Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs). The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP); this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP) gene and corrected by gene editing, proliferate on polylysine or ...
Electrospinning technique was used to fabricate polyvinyl alcohol (PVA)-based magnetic biodegradable nanofibers. PVA solution was mixed with ferrofluid or magnetic nanoparticles (MNPs) powder and formed two individual nanofibrous membranes (PVA/ferrofluid and PVA/MNPs powder) by electrospinning. The surface morphology of the nanofibrous membrane was characterized by scanning electron microscopy and the magnetic properties were measured by vibrating sample magnetometer. Macrophages (RAW 264.7) were co-cultured with the nanofibrous membranes for 12, 24, and 48 h and exhibited good cell viability (,95%). Results showed that the PVA fibers would be degraded and the embedded Fe{sub 3}O{sub 4} nanoparticles would be released and delivered to cells. ...
There has been a considerable growth and development in electrospun nanofibers for research activity, as well as commercial fabrication over the past couple of decades. These continuous nanofibers are solution driven exclusively by an electric field. Numerous studies on electrospun fibrous scaffolds have demonstrated sufficient mechanical properties and support of cell growth for tissue engineering. Despite these substantial achievements, there is still an Edisonian-type procedure to acquire the desired scaffold orientation and mechanical response that mimics the native tissue behavior. In this study, the electrospun scaffolds are fabricated with different fiber orientation -i.e. aligned and patterned (0/90) - by modifying the electrospinning process, specifically electric field and target, over large areas and lengths (30 mm x 30 mm). Mechanical behavior of controlled scaffold parameters at nanoscale, e.g., fiber orientation, and porosity, is investigated for an effective tissue replacement. In
Electrospun nanofibrous SF/P(LLA-CL) membrane: a potential substratum for endothelial keratoplasty Junzhao Chen,1,* Chenxi Yan,1,* Mengyu Zhu,1,* Qinke Yao,1 Chunyi Shao,1 Wenjuan Lu,1 Jing Wang,2 Xiumei Mo,2 Ping Gu,1 Yao Fu,1 Xianqun Fan1 1Department of Ophthalmology, Ninth Peoples Hospital, Shanghai Jiao Tong University School of Medicine, 2Biomaterials and Tissue Engineering Laboratory, College of Chemistry and Chemical Engineering and Biotechnology, Donghua University, Shanghai, Peoples Republic of China *These authors contributed equally to this work Background: Cornea transplant technology has progressed markedly in recent decades, allowing surgeons to replace diseased corneal endothelium by a thin lamellar structure. A thin, transparent, biocompatible, tissue-engineered substratum with corneal endothelial cells for endothelial keratoplasty is currently of interest. Electrospinning a nanofibrous structure can simulate the extracellular matrix and have beneficial effects for cell culture.
In this study, poly(vinyl alcohol) nanofibres were produced and evaluated for wound dressing applications. However, the solubility of the poly(vinyl alcohol) matrix in the aqueous medium generally limits its applications. To overcome this problem, 1,2,3,4 butanetetracarboxylic acid (BTCA) and citric acid (CA) were used as crosslinking agents. Successful bead-free nanofibres were produced, and they both preserved their fibrous structure after water treatment. The mean fibre diameters of polycarboxylic acid crosslinked nanofibres were lower compared to pure PVA nanofibres. Although the morphology of BTCA and CA crosslinked nanofibres was similar, the swelling degree of PVA/CA was found to be higher. Furthermore, toxicity and keratinocyte cell proliferation performance of produced PVA/BTCA and PVA/CA nanofibres indicated that these nanofibrous materials could be used in wound dressing applications. ...
Electrospinning is a versatile method to fabricate nanofibers of a range of polymeric and composite materials suitable as scaffolds for tissue engineering applications. In this study, we report the fabrication and characterization of polyaniline-carbon nanotube/poly(N-isopropyl acrylamide-co-methacrylic acid) (PANI-CNT/PNIPAm-co-MAA) composite nanofibers and PNIPAm-co-MAA nanofibers suitable as a three-dimensional (3D) conducting smart tissue scaffold using electrospinning. The chemical structure of the resulting nanofibers was characterized with FUR and H-1 NMR spectroscopy. The surface morphology and average diameter of the nanofibers were observed by SEM. Cellular response of the nanofibers was studied with mice L929 fibroblasts. Cell viability was checked on 7th day of cell culture by double staining the cells with calcein-AM and PI dye. PANI-CNT/PNIPAm-co-MAA composite nanofibers were shown the highest cell growth and cell viability as compared to PNIPAm-co-MAA nanofibers. Cell viability in ...
UCLA REBAR Lab Background: Traumatic peripheral nerve injuries can result in lifelong disability. Primary nerve repair is used for short nerve defects. Autologous nerve can be used in longer defects but creates donor site morbidity. Nerve conduits lack an aligned internal scaffold to support and guide axonal regeneration. Peptide amphiphiles (PA) can self-assemble into aligned nanofibers and promote peripheral nerve regeneration in vivo. Bioactive epitopes IKVAV (Ile-Lys-Val-Ala-Val) and RGDS (Arg-Gly-Asp-Ser) can be incorporated into PA nanofibers and can promote cell adhesion, growth, and migration. There are no studies to date that examine the ability of PA nanofibers to support the regeneration of injured nerves that supply the musculoskeletal system. In this preliminary study, we investigate the viability of rat Schwann cells after incorporation into PA gels.. Methods: PA nanofibers were synthesized by Stupp et al. PAs were aqueously dissolved, and rat Schwann cells (cell line RT4-D6P2T) ...
The study compared the biosensing properties of laccase biosensors based on carbon nanofibers (CNFs) and copper/carbon composite nanofibers (Cu/CNFs). The two kinds of nanofibers were prepared by electrospinning and carbonization under the same conditions. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy were employed to investigate the morphologies and structures of CNFs and Cu/CNFs. The amperometric results indicated that the Cu/CNFs/laccase(Lac)/Nafion/glass carbon electrode (GCE) possessed reliable analytical performance for the detection of catechol. The sensitivity of the Cu/CNFs/Lac/Nafion/GCE reached 33.1 μA/mM, larger than that of CNFs/Lac/Nafion/GCE. Meanwhile, Cu/CNFs/Lac/Nafion/GCE had a wider linear range from 9.95 × 10−6 to 9.76 × 10−3 M and a lower detection limit of 1.18 μM than CNFs/Lac/Nafion/GCE. Moreover, it exhibited a good repeatability, reproducibility, selectivity and long-term stability, revealing that electrospun Cu/CNFs have great
Immobilization of growth factors in scaffolds is important for controlling their dose and bioactivity for regenerative medicine applications. Although numerous covalent and noncovalent immobilization strategies have been proposed, better growth factor loading and dose control inside the scaffold is necessary. Nature of the binding site on the growth factor interacting with scaffold is critical for preserving and achieving maximal growth factor functionality, which has been a relatively less emphasized issue in previous studies. We recently reported heparin mimetic peptide nanofibers, which mimic chemistry of heparan sulfates. Heparin mimetic nanofibers were shown to bind to vascular endothelial growth factor (VEGF) and direct endothelial cells to angiogenesis. Here, we further investigated interactions between heparin mimetic peptide nanofibers and growth factors. We tested bioactivity of the nanofiber bound growth factors in order to understand the potential use of these peptide nanofiber ...
李盛红,吴大朋,闫晓辉,&关亚风.(2015).Acetone-activated polyimide electrospun nanofiber membrane forthin-film microextraction and thermal desorption-gas chromatography-mass spectrometric analysis of phenols in environmental water.JOURNAL OF CHROMATOGRAPHY A,1411(0),1 ...
In this thesis, changes in Youngs modulus of mesenchymal stem cells (MSCs) were investigated during their osteogenic differentiation on bioactive peptide nanofibers that bear triple glutamic acid sequence (EEE), a non-collagenous protein sequence of some extracellular matrix (ECM) proteins (e.g. bone sialoprotein) found in bone tissue. MSCs formed spherical cell aggregates on the osteoinductive peptide nanofibers, here also called osteospheroids, of which their cells made intensive cell-cell contacts and showed osteoblast-like cell morphology. Mechanical characterization of the osteospheroids on the peptide nanofiber hydrogel was performed using atomic force microscope (AFM) where AFM probes modified with a thin film coating of octa uorocyclobutane (C4F8) were used to measure force maps of the cells at days 3, 7 and 14 of osteogenic differentiation. Hertz Cone model, same as Sneddon, was applied to approach curves of 12 force curves per cell to calculate the Young s modulus values. As a result, ...
Stem cell and tissue engineering offer us with a unique opportunity to research and develop new therapies for treating various diseases that are otherwise incurable using traditional medicines. However, development of these new therapies replies upon the establishment of in vitro cell culture and differentiation systems that mimic in vivo microenvironments required for cell-cell and cell-ECM interaction. The development of these cell culture systems depends upon the identification of appropriate biomaterials and cell sources. Biomaterials should be carefully selected and fabricated into scaffolds for supporting cell growth and differentiation. In this study, we explored the fabrication of 3D electrospun nanofiber scaffolds and demonstrated the feasibility of using these scaffolds for supporting cell growth. The material that we used for scaffold fabrication is a polymer, polycaprolactone (PCL). We discovered that the electrospun PCL nanofibers are highly hydrophobic, unsuitable for cell growth. The
In this study, the adsorption of 1-chloro-4-nitrobenzene (1C4NB) on carbon nanofibers (CNFs), was investigated in a batch system. The combined effects of operating parameters such as contact time, pH, initial 1C4NB concentration, and CNFs dosage on the adsorption of 1C4NB byCNFs were analyzed using response surface methodology (RSM). The analysis of variance results confirmed that there was significant agreement between the model and experimental data. In addition, it was indicated that the residuals followed a normal distribution.The screening experiments showed that significant factors in 1C4NB removal were CNFs dosage, interaction between initial 1C4NB concentration-CNFs dosage and CNFs dosage-contact time. High efficiency removal (|90%) was obtained under optimal value of process parameters in the first 6 min of the removal process. The results indicate that RSM is a suitable method for modeling and optimizing the process, so that experimental design by RSM leads to time and cost saving.Non-linear
Among the synthetic polymers, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) microbial polyester is one of the biocompatible and biodegradable copolymers in the nanomedicine scope. PHBV has key points and suitable properties to support cellular adhesion, proliferation and differentiation of nanofibers. Nanofibers are noticeably employed in order to enhance the performance of biomaterials, and could be effectively considered in this scope. Electrospinning is one of the well-known and practical methods that extremely employed in the construction of nanofibrous scaffolds for biomedical application and recently PHBV has exploited in nerve graft and regenerative medicine. PHBV composites nanofibrous scaffolds are able to be applied as promising materials in many fields, such as; wound healing and dressing, tissue engineering, targeted drug delivery systems, functional carries, biosensors or nano-biosensors and so on. In this mini-review, we attempt to provide a more detailed overview of the recent
Water, among the most valuable natural resources available on earth, is under serious threat as a result of undesirable human activities: for example, marine dumping, atmospheric deposition, domestic, industrial and agricultural practices. Optimizing current methodologies and developing new and effective techniques to remove contaminants from water is the current focus of interest, in order to renew the available water resources. Materials like nanoparticles, polymers, and simple organic compounds, inorganic clay materials in the form of thin film, membrane or powder have been employed for water treatment. Among these materials, membrane technology plays a vital role in removal of contaminants due to its easy handling and high efficiency. Though many materials are under investigation, nanofibers driven membrane are more valuable and reliable. Synthetic methodologies applied over the modification of membrane and its applications in water treatment have been reviewed in this article.
The clinical development of neuropeptides has been limited by a combination of the short plasma half-life of these drugs and their ultimate failure to permeate the blood brain barrier. Peptide nanofibres have been used to deliver peptides across the blood brain barrier and in this work we demonstrate that the polymer coating of peptide nanofibres further enhances peptide delivery to the brain via the intravenous route. Leucine(5)-enkephalin (LENK) nanofibres formed from the LENK ester prodrug - tyrosinyl(1)palmitate-leucine(5)-enkephalin (TPLENK) were coated with the polymer - N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) and injected intravenously. Peptide brain delivery was enhanced because the GCPQ coating on the peptide prodrug nanofibres, specifically enables the peptide prodrug to escape liver uptake, avoid enzymatic degradation to non-active sequences and thus enjoy a longer plasma half life. Plasma half-life is increased 520%, liver AUC0-4 decreased by ...
A hybrid electrode material for high-power supercapacitors was fabricated by grafting carbon nanofibers (CNFs) onto the surface of powdered activated carbon (AC) through catalytic chemical vapor deposition (CCVD). A uniform thin layer of disentangled CNFs with a herringbone structure was deposited on the carbon surface through the decomposition of propane at 450 °C over an AC-supported nickel catalyst. CNF coating was controlled by the reaction time and the nickel content. The superior CNF/AC composite displays excellent electrochemical performance in a 0.5 mol L−1 solution of K2SO4 due to its unique structure. At a high scan rate (100 mV s−1) and current loading (20 A g−1), the capacitance values were three- and fourfold higher than those for classical AC/carbon black composites. Owing to this feature, a high energy of 10 Wh kg−1 was obtained over a wide power range in neutral medium at a voltage of 0.8 V. The significant enhancement of charge propagation is attributed to the presence ...
An ultra-facile fabrication process for the preparation of phosphorus doped porous carbon nanofibers (P-PCNFs) through the electrospinning and heat treatment method has been studied. The materials were characterized by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. Studies showed that fabricated P-PCNFs have unique porous fibers structures, large specific surface area (462.83 cm2 g−1), and abundant microporous and mesoporous structures. X-ray photoelectron spectroscopy analyses revealed that the contents of phosphorus and electrochemical properties in a series of P-PCNF samples can be tuned by controlling the polyphosphoric acid concentration. The electrochemical properties of the materials were evaluated using cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. Studies showed that the specific capacitance of the fabricated P-PCNFs using the ultra-facile process reached up to 228.7 F g−1 at 0.5 A g−1 in 1 M ...
Site of the Professor Mohamed Hassan Abdelwahab El-Newehy: Academic Coordination Officer_DSP-KSU related to Faculties Websites at King Saud University
The nanofiber technology of present interest focuses on the electrospinning technique, which conveniently allows the preparation of fibrous materials with very fine diameters ranging from submicron to several nanometers. With the ability to form nanofibrous structures, a drive to mimic the extracellular matrix (ECM) and form scaffolds that are an artificial ECM suitable for tissue formation has begun. In addition, nanofibrous scaffolds have a high surface area-to-volume ratio, which is thought to enhance cell adhesion. Cell migration, proliferation and differentiation are dependent on adhesion and should be enhanced on nanofibrous scaffolds. Based on these, the main goals of the present work were to produce biodegradable nanofiber meshes with different topographies by electrospinning, in order to obtain diverse porosities and texture; to perform in vitro studies with an established cell line of Human primary osteogenic sarcoma (SaOs-2 cells), in order to observe cellular performance over these nanofiber
Researchers from the University of California-Riverside have announced the development of a low cost and efficient catalyst material used in polymer electrolyte membrane (PEM) fuel cells.. While traditional PEM catalysts depend on expensive platinum (Pt), this catalyst uses more abundant (and cheaper) metals (cobalt, iron, nickel) that are integrated into engineered carbon-fiber membranes to achieve needed performance in the fuel cell reaction.. Using a technique called electrospinning, the UCR researchers made paper-thin sheets of carbon nanofibers that contained metal ions - either cobalt, iron or nickel. Upon heating, the ions formed ultrafine metal nanoparticles that catalyzed the transformation of carbon into a high-performance graphitic carbon. Subsequently, the metal nanoparticles and residual nongraphitic carbon were oxidized, leading to a highly porous and useful network of metal oxide nanoparticles dispersed in a porous network of graphite.. If the membrane is able to tolerate carbon ...
Motoyama, Y., Lee, Y., Tsuji, K., Yoon, S.-H., Mochida, I. and Nagashima, H. (2011), Platinum Nanoparticles Supported on Nitrogen-doped Carbon Nanofibers as Efficient Poisoning Catalysts for the Hydrogenation of Nitroarenes. ChemCatChem, 3: 1578-1581. doi: 10.1002/cctc.201100135 ...
Page contains details about tin quantum dots-embedded carbon nanofibers . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com
TY - CONF. T1 - Risk assessment of polymer composites containing cellulose nanofibrils (CNF). AU - Kangas, Heli. AU - Pitkänen, Marja. AU - Wikström, Lisa. AU - Mannila, Juha. N1 - LIS: Abstract reviewed PY - 2016. Y1 - 2016. N2 - Cellulose nanofibrils (CNFs) have shown potential as strengthening agents in polymer composites. In addition, as bio-based nanomaterials originating from abundant raw material source, they offer sustainable alternative for manufacturing of light-weight composites with reduced carbon footprint. In general, CNFs have been found to pose no immediate threat to human health or to the environment. However, exposure to CNFs during production, use or end-of-life may lead, for example, to inflammatory effects of employees or unwanted adverse effects in the environment. In this presentation, risk assessment performed to polymer nanocomposites containing CNF will be reported. Exposure assessment will take into account occupational and consumer exposure as well as exposure to ...
Enhanced Critical Size Defect Repair in Rabbit Mandible by Electrospun Gelatin-β-TCP Composite Nanofibrous Membranes. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
The ability of dendritic cells to coordinate innate and adaptive immune responses makes them essential targets for vaccination strategies. Presentation of specific antigens by dendritic cells is required for the activation of the immune system against many pathogens and tumors, and nanoscale materials can be functionalized for active targeting of dendritic cells. In this work, we integrated an immunogenic, carbohydrate melanoma-associated antigen-mimetic GM3-lactone molecule into mannosylated peptide amphiphile nanofibers to target dendritic cells through DC-SIGN receptor. Based on morphological and functional analyses, when dendritic cells were treated with peptide nanofiber carriers, they showed significant increase in antigen internalization and a corresponding increase in the surface expression of the activation and maturation markers CD86, CD83 and HLA-DR, in addition to exhibiting a general morphology consistent with dendritic cell maturation. These results indicate that mannosylated ...
TY - JOUR. T1 - Simultaneous electrospin-electrosprayed biocomposite nanofibrous scaffolds for bone tissue regeneration. AU - Francis, Lijo. AU - Venugopal, J.. AU - Prabhakaran, Molamma P.. AU - Thavasi, V.. AU - Marsano, E.. AU - Ramakrishna, S.. PY - 2010/10. Y1 - 2010/10. N2 - Currently, the application of nanotechnology in bone tissue regeneration is a challenge for the fabrication of novel bioartificial bone grafts. These nanostructures are capable of mimicking natural extracellular matrix with effective mineralization for successful regeneration of damaged tissues. The simultaneous electrospraying of nanohydroxyapatite (HA) on electrospun polymeric nanofibrous scaffolds might be more promising for bone tissue regeneration. In the current study, nanofibrous scaffolds of gelatin (Gel), Gel/HA (4:1 blend), Gel/HA (2:1 blend) and Gel/HA (electrospin-electrospray) were fabricated for this purpose. The morphology, chemical and mechanical stability of nanofibres were evaluated by means of field ...
Introducing porosity in electrospun scaffolds is critical to improve cell penetration and nutrient diffusion for tissue engineering. Nanofibrous cellulose scaffolds were prepared by electrospinning cellulose acetate (CA) followed by saponification to regenerate cellulose. Using a computer-assisted design approach, scaffolds underwent laser ablation resulting in pores with diameters between 50 and 300 mu m. without damaging or modifying the surrounding scaffold area. A new mineralization method was employed in conjunction with microablation using commercial phosphate buffered saline (PBS) to soak carboxymethylcellulose surface-modified electrospun scaffolds. The resulting crystals within the scaffold on the interior of the pore had a calcium to phosphate ratio of 1.56, similar to hydroxyapatite. It was observed that porosity of the cellulose scaffolds enhanced osteoblast cell attachment at the edge of the pores, while mineralization enhanced overall cell density.
Composite fibres with a matrix of poly(ethylene glycol) (PEG) and cellulose nanofibrils (CNF) as reinforcing elements were produced using a capillary viscometer. Two types of CNF were employed: one based on carboxymethylated pulp fibres and the other on TEMPO-oxidized pulp. Part of the latter nanofibrils was also grafted with PEG in order to improve the compatibility between the CNF and the PEG matrix. The nominal CNF-content was kept at 10 or 30 weight-%. The composite fibres were characterized by optical and scanning electron microscopy in addition to dynamic mechanical thermal analysis (DMTA). Evaluation of the storage modulus indicated a clear reinforcing effect of the CNF, more pronounced in the case of the grafted CNF and depending on the amount of CNF. An interesting feature observed during the DMTA-measurements was that the fibrils within the composite fibres appeared to forma rather coherent and load-bearing network which was evident even after removing of the PEG-phase (by melting). An ...
Superhydrophobic electrospun polyacrylonitrile nanofibre membranes have been prepared by surface coating of silica nanoparticles and fluorinated alkyl silane. The coated membranes were characterised by scanning electron microscopy, water contact angle, thermogravimetry analysis, Brunauer-Emmett-Teller, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and atomic force microscopy. It was shown that the loading of nanoparticle on the nanofibre membrane was controlled by the particle concentration in the coating solution, which played a critical role in the formation of superhydrophobic surface. Increased particle loading led to higher surface roughness and WCA. The nanoparticle coating had little influence on the porosity of the nanofibre membranes. However, overloading of the particles would affect the specific surface area of the nanofibre membrane ...
TY - JOUR. T1 - Tubular hydrogels of circumferentially aligned nanofibers to encapsulate and orient vascular cells. AU - McClendon, Mark T.. AU - Stupp, Samuel I.. PY - 2012/8. Y1 - 2012/8. N2 - There is a great clinical need for tissue engineered blood vessels that could be used to replace or bypass damaged arteries. The success of such grafts will depend strongly on their ability to mimic the cellular and matrix organization found in native arteries, but currently available cell scaffolds such as electrospun fibers or hydrogels lack the ability to simultaneously encapsulate and align cells. Our laboratory has recently developed liquid crystalline solutions of peptide amphiphile nanofibers that form aligned domains at exceedingly low concentrations (,1wt%), and can be trapped as gels with macroscopic alignment using low shear rates and ionic crosslinking. We describe here the use of these systems to fabricate tubes with macroscopic circumferential alignment and demonstrate their potential as ...
One of the possible applications of nanofibres is water filtration. For this application a nanofibre flat-sheet membrane can be produced that can be used as a water filtration membrane. More specifically, this can be used in microfiltration. Due to their higher porosities and interconnected pore structures, nanofibres offer a higher permeability to water filtration than conventional materials currently in use (Thavasi et al., 2008). This study aims at assessing the possible use of electrospun nanofibre filters in water filtration. Firstly, physical properties such as clean water permeability (CWP) and strength were examined. Secondly, the use of the membrane (functionalised or non-functionalised) for the removal of pathogens was investigated and compared to previous studies. Thirdly, the application of the electrospun membranes for wastewater filtration in a submerged MBR was investigated. Methods. Membrane production process. The standard set-up for electrospinning consists of a spinneret with ...
Surface properties of scaffolds such as hydrophilicity and the presence of functional groups on the surface of scaffolds play a key role in cell adhesion, proliferation and migration. Different modification methods for hydrophilicity improvement and introduction of functional groups on the surface of scaffolds have been carried out on synthetic biodegradable polymers, for tissue engineering applications. In this study, alkaline hydrolysis of poly (ε-caprolactone) (PCL) nanofibrous scaffolds was carried out for different time periods (1 h, 4 h and 12 h) to increase the hydrophilicity of the scaffolds. The formation of reactive groups resulting from alkaline hydrolysis provides opportunities for further surface functionalization of PCL nanofibrous scaffolds. Matrigel was attached covalently on the surface of an optimized 4 h hydrolyzed PCL nanofibrous scaffolds and additionally the fabrication of blended PCL/matrigel nanofibrous scaffolds was carried out. Chemical and mechanical characterization ...
Transplanted retinal pigment epithelium (RPE) cells hold promise for treatment of age-related macular degeneration (AMD) and Stargardt disease (SD), but it is conceivable that the degenerated host Bruchs membrane (BM) as a natural substrate for RPE might not optimally support transplanted cell survival with correct cellular organization. We fabricated novel ultrathin three-dimensional (3-D) nanofibrous membranes from collagen type I and poly(lactic-co-glycolic acid) (PLGA) by an advanced clinical-grade needle-free electrospinning process. The nanofibrillar 3-D networks closely mimicked the fibrillar architecture of the native inner collagenous layer of human BM. Human RPE cells grown on our nanofibrous membranes bore a striking resemblance to native human RPE. They exhibited a correctly orientated monolayer with a polygonal cell shape and abundant sheet-like microvilli on their apical surfaces. RPE cells built tight junctions and expressed RPE65 protein. Flat 2-D PLGA film and cover glass as ...
TY - JOUR. T1 - Cellulose nanofibre aerogel filter with tuneable pore structure for oil/water separation and recovery. AU - He, Zhiyong. AU - Zhang, Xiwang. AU - Batchelor, Warren Jeffrey. PY - 2016. Y1 - 2016. N2 - A cellulose nanofibre aerogel filter with tuneable pore structure exhibiting super-hydrophilic and underwater-super-oleophobic behaviours is synthesized by a facile method of cross-linking between cellulose nanofibres and polyamideamine-epichlorohydrin (PAE). The prepared aerogel filter showed excellent oil/water separation efficiency for both oil/water mixtures (100 , even after 10 cycles), and oil/water surfactant-free emulsion (98.6 ), which is driven solely by gravity. In addition, the specific structure can de-emulsify oil/water emulsion. The results showed that the cellulose aerogel filter can be used for oil/water separation and recovery.. AB - A cellulose nanofibre aerogel filter with tuneable pore structure exhibiting super-hydrophilic and underwater-super-oleophobic ...
We report humidity sensing characteristics of CdTiO3 nanofibers prepared by electrospinning. The nanofibers were porous having an average diameter and length of similar to 50-200 nm and similar to 100 mu m, respectively. The nanofiber humidity sensor was fabricated by defining aluminum electrodes using photolithography on top of the nanofibers deposited on glass substrate. The performance of the CdTiO3 nanofiber humidity sensor was evaluated by AC electrical characterization from 40% to 90% relative humidity at 25 degrees C. The frequency of the AC signal was varied from 10(-1) to 10(6) Hz. Fast response time and recovery time of 4 s and 6 s were observed, respectively. The sensor was highly sensitive and exhibited a reversible response with small hysteresis of less than 7%. Long term stability of the sensor was confirmed during 30 day test. The excellent sensing characteristics prove that the CdTiO3 nanofibers are potential candidate for use in high performance humidity sensors.. ...
Recent work demonstrates that osteoprogenitor cell culture on nanofiber scaffolds can promote differentiation. This response may be driven by changes in cell morphology caused by the three-dimensional (3D) structure of nanofibers. We hypothesized that nanofiber effects on cell behavior may be mediated by changes in organelle structure and function. To test this hypothesis, human bone marrow stromal cells (hBMSCs) were cultured on poly(ϵ-caprolactone) (PCL) nanofibers scaffolds and on PCL flat spuncoat films. After 1 day-culture, hBMSCs were stained for actin, nucleus, mitochondria, and peroxisomes, and then imaged using 3D confocal microscopy. Imaging revealed that the hBMSC cell body (actin) and peroxisomal volume were reduced during culture on nanofibers. In addition, the nucleus and peroxisomes occupied a larger fraction of cell volume during culture on nanofibers than on films, suggesting enhancement of the nuclear and peroxisomal functional capacity. Organelles adopted morphologies with greater 3D
The penetration and residence of vertically aligned carbon nanofibers (VACNF) within live cell matrices is demonstrated upon substrates that incorporate spatially registered indices to facilitate temporal tracking of individual cells. Penetration of DNA-modified carbon nanofibers into live cells using this platform provides efficient delivery and expression of exogenous genes, similar to microinjection-styled methods, but on a massively parallel basis. Spatially registered indices on the substrate allow one to conveniently locate individual cells, facilitating temporal tracking of gene expression events. We describe fabrication and use of this gene delivery platform which consists of arrays of individual carbon nanofibers at 5 ...
TY - JOUR. T1 - Capturing the stem cell paracrine effect using heparin-presenting nanofibres to treat cardiovascular diseases. AU - Webber, Matthew J.. AU - Han, Xiaoqiang. AU - Prasanna Murthy, S. N.. AU - Rajangam, Kanya. AU - Stupp, Samuel I. AU - Lomasney, Jon W.. PY - 2010/12. Y1 - 2010/12. N2 - The mechanism for stem cell-mediated improvement following acute myocardial infarction has been actively debated. We support hypotheses that the stem cell effect is primarily paracrine factor-linked. We used a heparin-presenting injectable nanofibre network to bind and deliver paracrine factors derived from hypoxic conditioned stem cell media to mimic this stem cell paracrine effect. Our self-assembling peptide nanofibres presenting heparin were capable of binding paracrine factors from a medium phase. When these factor-loaded materials were injected into the heart following coronary artery ligation in a mouse ischaemia-reperfusion model of acute myocardial infarction, we found significant ...
Polycaprolactone (PCL) has been regarded as a promising synthetic material for bone tissue engineering application. Owing to its unique biochemical properties and great compatibility, PCL fibers have come to be explored as a potential delivering scaffold for stem cells to support bone regeneration during clinical application. The human derived mesenchymal stem cells (MSCs) were obtained from umbilical cord (UC), bone marrow (BM), and adipose tissue (AD), respectively. The osteogenic differentiation potency of various human MSCs on this novel synthetic biomaterial was also investigated in vitro. Here, we illustrated that those human UC-, BM-, and AD-derived MSCs exhibited fibroblast-like morphology and expressed characteristic markers. Impressively, PCL nanofiber scaffold could support those MSC adhesion and proliferation. Long-term culture on PCL nanofiber scaffold maintained the viability as well as accelerated the proliferation of those three different kinds of human MSCs. More importantly, the
Page contains details about MCP-1/IL-4 chemokines-loaded SLac peptide nanofibers hydrogel . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com
Generally, although the conventional drug delivery systems, such as using only pHdependent polymers or time-dependent release systems are popular, the individuals variations of physiological conditions usually lead to premature or imperfect drug release from each of these systems. Therefore, a combination of pH- and time-dependent polymers could be more reliable for delivering drugs to the lower GI tract such as colon. To this end, electrospinning method was used as a fabrication approach for preparing electrospun nanofibers of indomethacin aimed for colon delivery. Formulations were prepared based on a 3 2 full factorial design. Independent variables were the drug:polymer ratio (with the levels of 3:5, 4.5:5 and 6:5 w/w) and Eudragit S:Eudragit RS w/w ratio (20:80, 60:40 and 100:0). The evaluated responses were drug release at pH 1.2, 6.4, 6.8 and 7.4. Combinations of Eudragit S (ES), Eudragit RS (ERS) and drug based on factorial design were loaded in 10 ml syringes. 3 Electrospinning method ...
Generally, although the conventional drug delivery systems, such as using only pHdependent polymers or time-dependent release systems are popular, the individuals variations of physiological conditions usually lead to premature or imperfect drug release from each of these systems. Therefore, a combination of pH- and time-dependent polymers could be more reliable for delivering drugs to the lower GI tract such as colon. To this end, electrospinning method was used as a fabrication approach for preparing electrospun nanofibers of indomethacin aimed for colon delivery. Formulations were prepared based on a 3 2 full factorial design. Independent variables were the drug:polymer ratio (with the levels of 3:5, 4.5:5 and 6:5 w/w) and Eudragit S:Eudragit RS w/w ratio (20:80, 60:40 and 100:0). The evaluated responses were drug release at pH 1.2, 6.4, 6.8 and 7.4. Combinations of Eudragit S (ES), Eudragit RS (ERS) and drug based on factorial design were loaded in 10 ml syringes. 3 Electrospinning method ...
COMPOSITION AND METHOD FOR SELF-ASSEMBLY AND MINERALIZATION OF PEPTIDE-AMPHIPHILES - The present invention is directed to a composition useful for making homogeneously mineralized self assembled peptide-amphiphile nanofibers and nanofiber gels. The composition is generally a solution comprised of a positively or negatively charged peptide-amphiphile and a like signed ion from the mineral. Mixing this solution with a second solution containing a dissolved counter-ion of the mineral and/or a second oppositely charged peptide amphiphile, results in the rapid self assembly of the peptide-amphiphiles into a nanofiber gel and templated mineralization of the ions. Templated mineralization of the initially dissolved mineral cations and anions in the mixture occurs with preferential orientation of the mineral crystals along the fiber surfaces within the nanofiber gel. One advantage of the present invention is that it results in homogenous growth of the mineral throughout the nanofiber gel. Another ...
This work describes the measurement and comparison of several important properties of native cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs), such as crystallinity, morphology, aspect ratio, and surface chemistry. Measurement of the fundamental properties of seven different CNCs/CNFs, from raw material sources (bacterial, tunicate, and wood) using typical hydrolysis conditions (acid, enzymatic, mechanical, and 2,2,6,6-tetramethylpiperidiny1-1-oxyl (TEMPO)-mediated oxidation), was accomplished using a variety of measurement methods. Atomic force microscopy (AFM), transmission electron microscopy (TEM), and C-13 cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) spectroscopy were used to conclude that CNCs, which are rodlike in appearance, have a higher crystallinity than CNFs, which are fibrillar in appearance. CNC aspect ratio distributions were measured and ranged from 148 +/- 147 for tunicate-CNCs to 23 +/- 12 for wood-CNCs. Hydrophobic ...
Eectrospinning a versatile and the most preferred technique for the fabrication of nanofibers has revolutionized by opening unlimited avenues in biomedical fields. Electrospinning is being used for fabricating nanofibers for various biomedical and dental applications such as tooth regeneration, wound healing and prevention of dental caries. Discover the latest research on electrospinning and nanofibers here. ...
Alginate nanofibers, scaffolds that include alginate nanofibers, implantable devices that include alginate nanofibers, and methods for making the alginate nanofibers by electrospinning.
Abstract. The ability to control the permeability of a synthetic membrane structure formed by a spatially stochastic forest of vertically aligned carbon nanofibres is demonstrated. Control of membrane pore size and morphology was achieved by varying the thickness of a uniform, conformal coating of SiO2 on the nanofibre surfaces. Characterization of passive diffusion using fluorescence microscopy and labelled latex beads confirms the ability to alter membrane permeability. Further, statistically reproducible transport regimes are predicted for the spatially stochastic membrane as a function of the nanofibre diameter by a Monte Carlo simulation technique. Realizing predictable nanoscale behaviour in a microscopically random, statistical structure is essential for applications requiring controlled, species specific transport.. Print publication: Issue 12 (December 2005) ...
0059] Multiphase tissue scaffolds of this disclosure comprising PCL nanofibers and multiphase tissue scaffolds of this disclosure comprising PCL nanofibers, each seeded with PDL cells, were prepared. Experiments were performed comparing cell viability, alignment, proliferation, alkaline phosphatase (ALP activity) and collagen deposition on these different scaffolds. Results are depicted in FIGS. 8 through 14. As shown in FIG. 8, cell growth was similar on PLGA and PCL aligned nanofiber scaffolds on days 1, 7, 14 and 28. Also similar on the aligned PLGA and PCL nanofiber scaffolds were ALP activity (see FIG. 9A) and collagen deposition (see FIG. 9B). Cells attached and were viable on the non-mineralized ligament phase, and mineralized phase and the transition region of the two phases after one day of culture on the aligned PCL nanofiber scaffold (see FIG. 10). However, greater cell proliferation was observed on the mineralized phase of the aligned PLGA nanofiber scaffolds at Day 28 (see FIG. 11). ...