This review summarizes and broadly classifies all of the major sustainable natural carbohydrate bio-macromolecular manifestations in nature - from botanical (cellulose, starch, and pectin), seaweed (alginate, carrageenan, and agar), microbial (bacterial cellulose, dextran, and pullulan), and animal (hyaluronan, heparin, chitin, and chitosan) sources - that have been contrived into electrospun fibers. Furthermore, a relative study of these biomaterials for the fabrication of nanofibers by electrospinning and their characteristics viz. solution behavior, blending nature, as well as rheological and fiber attributes are discussed. The potential multidimensional applications of nanofibers (filtration, antimicrobial, biosensor, gas sensor, energy storage, catalytic, and tissue engineering) originating from these polysaccharides and their major impacts on the properties, functionalities, and uses of these electrospun fibers are compared and critically examined.
- MeSH
- agar chemie MeSH
- algináty chemie MeSH
- biokompatibilní materiály chemie MeSH
- celulosa chemie MeSH
- chitin chemie MeSH
- chitosan chemie MeSH
- dextrany chemie MeSH
- elektrochemické techniky MeSH
- glukany chemie MeSH
- heparin chemie MeSH
- karagenan chemie MeSH
- kyselina hyaluronová chemie MeSH
- lidé MeSH
- nanotechnologie metody MeSH
- nanovlákna chemie ultrastruktura MeSH
- pektiny chemie MeSH
- škrob chemie MeSH
- tkáňové inženýrství metody MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Anastomotic leakage is a severe complication in gastrointestinal surgery. It is often a reason for reoperation together with intestinal passage blockage due to formation of peritoneal adhesions. Different materials as local prevention of these complications have been studied, none of which are nowadays routinely used in clinical practice. Nanofabrics created proved to promote healing with their structure similar to extracellular matrix. We decided to study their impact on anastomotic healing and formation of peritoneal adhesions. We performed an experiment on 24 piglets. We constructed 3 hand sutured end-to-end anastomoses on the small intestine of each pig. We covered the anastomoses with a sheet of polycaprolactone nanomaterial in the first experimental group, with a sheet of copolymer of polylactic acid with polycaprolactone in the second one and no fortifying material was used in the Control group. The animals were sacrificed after 3 weeks of observation. Clinical, biochemical and macroscopic signs of anastomotic leakage or intestinal obstruction were monitored, the quality of the scar tissue was assessed histologically, and a newly developed scoring system was employed to evaluate the presence of adhesions. The material is easy to manipulate with. There was no mortality or major morbidity in our groups. No statistical difference was found inbetween the groups in the matter of level of peritoneal adhesions or the quality of the anastomoses. We created a new adhesion scoring system. The material appears to be safe however needs to be studied further to prove its' positive effects.
- MeSH
- adheze tkání etiologie prevence a kontrola MeSH
- anastomóza chirurgická MeSH
- duodenum chirurgie MeSH
- hojení ran MeSH
- mikroskopie elektronová rastrovací MeSH
- modely nemocí na zvířatech MeSH
- náhodné rozdělení MeSH
- nanovlákna terapeutické užití ultrastruktura MeSH
- nemoci peritonea etiologie prevence a kontrola MeSH
- netěsnost anastomózy prevence a kontrola MeSH
- polyestery MeSH
- prasata MeSH
- testování materiálů MeSH
- tkáňové podpůrné struktury * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Over the last few years, the electrospinning technique has attracted significant attention for the production of novel nanofibrous materials. At the same time, the use of graphene oxide and the natural products extracted from plants and/or trees have become very popular in various fields of science. In this work, a new method for the production of nanofibers based on a combination of Gum Arabic (GA), as a natural tree gum exudate, PVA, as an environmentally-friendly stabilizer, and graphene oxide (GO) has been developed and characterized. SEM analysis showed fundamental differences on the surface of bare nanofibers with and without GO, and also significantly smaller fiber diameters in the case of the presence of GO (fibers <100 nm present). Raman spectroscopy confirmed and TGA analysis approximated the content of GO in the nanofibers. Adsorption of methylene blue on the produced nanofibrous membrane was about 50% higher in the presence of GO, which opens the possibility to use GO/GA/PVA fibers in several applications, for example for the removal of dyes.
- MeSH
- adsorpce MeSH
- arabská guma chemie MeSH
- chemické látky znečišťující vodu izolace a purifikace MeSH
- elektrochemické techniky MeSH
- grafit chemie MeSH
- kinetika MeSH
- lidé MeSH
- methylenová modř izolace a purifikace MeSH
- nanovlákna chemie ultrastruktura MeSH
- polyvinyly chemie MeSH
- velikost částic MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Polyacrylonitrile (PAN) membranes have been prepared using needleless electrospinning with wire electrode and characterized by a series of methods HRSEM, XRD, air permeability and area weight measurements in dependence of high voltage and electrode distance. HRSEM analysis revealed the tendency to longitudinal rolling of strip-shaped PAN fibers forming hollow fibers. Combination of XRD analysis and molecular modeling explains this phenomenon as the consequence of the specific crystal structure of PAN fibers, where the isotactic PAN chains are arranged in layers forming belt shaped nanofibers with the strong tendency to roll up longitudinally forming hollow fibers. This effect offers the possibility to create hollow nanofibers by electrospinning with the appropriate choice of structure of polymer chains.
Poly(d,l-lactide)/polyethylene glycol (PLA/PEG) micro/nanofibers loaded with paclitaxel (PTX, 10 wt%) were prepared by needless electrospinning technology, which allows large scale production for real medicinal practice. The fiber structure and properties were investigated by several methods including scanning electron microscopy, nitrogen adsorption/desorption isotherm measurements, differential scanning calorimetry, and X-ray diffraction measurements to examine their morphology (fiber diameter distribution, specific surface area, and total pore volume), composition, drug-loading efficiency, and physical state. An HPLC-UV method was optimized and validated to quantify in vitro PTX release into PBS. The results showed that the addition of PEG into PLA fibers promoted the release of higher amounts of hydrophobic PTX over prolonged time periods compared to fibers without PEG. An in vitro cell assay demonstrated the biocompatibility of PLA/PEG fibrous materials and showed significant cytotoxicity of PTX-loaded PLA/PEG fibers against a human fibrosarcoma HT1080 cell line. The chick chorioallantoic membrane assay proved that PTX-loaded fibers exhibited antiangiogenic activity, with a pronounced effect in the case of the PEG-containing fibers. In vivo evaluation of PTX-loaded PLA/PEG fibers in a human fibrosarcoma recurrence model showed statistically significant inhibition in tumor incidence and growth after primary tumor resection compared to other treatment groups.
- MeSH
- buněčná smrt účinky léků MeSH
- difrakce rentgenového záření MeSH
- inhibitory angiogeneze farmakologie MeSH
- kur domácí MeSH
- lidé MeSH
- lokální recidiva nádoru patologie prevence a kontrola MeSH
- myši nahé MeSH
- nádorové buněčné linie MeSH
- nanovlákna chemie ultrastruktura MeSH
- nosiče léků chemie MeSH
- paclitaxel farmakologie MeSH
- polyestery chemie MeSH
- polyethylenglykoly chemie MeSH
- tělesná hmotnost MeSH
- teplota MeSH
- tumor burden účinky léků MeSH
- uvolňování léčiv * MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Aqueous dispersions of sulfonated polystyrene nanoparticles (average diameter: 30 ± 14 nm) with encapsulated 5,10,15,20-tetraphenylporphyrin (TPP) are promising candidates for antibacterial treatments due to the photogeneration of cytotoxic singlet oxygen species O2(1Δg) under physiological conditions using visible light. The antibacterial effect on gram-negative Escherichia coli was significantly enhanced after the addition of nontoxic potassium iodide (0.001-0.01 M) because photogenerated O2(1Δg) oxidized iodide to I2/I3-, which is another antibacterial species. The improved antibacterial properties were predicted using luminescence measurements of O2(1Δg), transient absorption of TPP triplets and singlet oxygen-sensitized delayed fluorescence (SODF). In contrast to a solution of free photosensitizers, the aqueous dispersion of photoactive nanoparticles did not exhibit any quenching of the excited states after the addition of iodide or any tendency toward aggregation and/or I3--induced photo-aggregation. We also observed a decrease in the lifetime of O2(1Δg) and a significant increase in SODF intensity at higher temperatures, due to the increased oxygen diffusion coefficient in nanoparticles and aqueous surroundings. This effect corresponds with the significantly stronger antibacterial effect of nanoparticles at physiological temperature (37 °C) in comparison with that at room temperature (25 °C).
- MeSH
- antibakteriální látky farmakologie MeSH
- časové faktory MeSH
- Escherichia coli účinky léků MeSH
- fotosenzibilizující látky farmakologie MeSH
- jodidy farmakologie MeSH
- kinetika MeSH
- luminiscence MeSH
- mikrobiální testy citlivosti MeSH
- nanočástice chemie ultrastruktura MeSH
- nanovlákna chemie ultrastruktura MeSH
- teplota * MeSH
- Publikační typ
- časopisecké články MeSH
In the present work, we developed a novel needleless emulsion electrospinning technique that improves the production rate of the core/shell production process. The nanofibres are based on poly-ε-caprolactone (PCL) as a continuous phase combined with a droplet phase based on Pluronic F-68 (PF-68). The PCL-PF-68 nanofibres show a time-regulated release of active molecules. Needleless emulsion electrospinning was used to encapsulate a diverse set of compounds to the core phase [i.e. 5-(4,6-dichlorotriazinyl) aminofluorescein -PF-68, horseradish peroxidase, Tetramethylrhodamine-dextran, insulin growth factor-I, transforming growth factor-β and basic fibroblast growth factor]. In addition, the PF-68 facilitates the preservation of the bioactivity of delivered proteins. The system's potential was highlighted by an improvement in the metabolic activity and proliferation of mesenchymal stem cells. The developed system has the potential to deliver susceptible molecules in tissue-engineering applications.
- MeSH
- biokompatibilní materiály farmakologie MeSH
- dextrany chemie MeSH
- emulze chemie MeSH
- jehly MeSH
- kolagen typ II metabolismus MeSH
- křenová peroxidasa metabolismus MeSH
- mezenchymální kmenové buňky cytologie účinky léků metabolismus MeSH
- mezibuněčné signální peptidy a proteiny farmakologie MeSH
- miniaturní prasata MeSH
- nanovlákna chemie ultrastruktura MeSH
- poloxamer chemie MeSH
- polyestery chemie MeSH
- prasata MeSH
- proteiny aplikace a dávkování MeSH
- rhodaminy chemie MeSH
- tkáňové inženýrství metody MeSH
- tkáňové podpůrné struktury chemie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The nanofiber scent carriers prepared by electrospinning from poly-vinyl-butyral (PVB), poly-ε-polycaprolactone (PCL), poly-vinyl- alcohol (PVA) and nylon 6/6 were tested as materials for collecting and preserving cigarette tobacco olfactory trace. Nanofiber material can include polar groups on its surface that influence wettability and also attracting of specific molecules creating olfactory trace. Nanofiber material and Aratex were also morphologicaly compared by scanning electron microscope (SEM) where nanofiber carrier had from twenty-two times to thirty-six times smaller fibre diameter than Aratex fibres. Olfactory testing of nanofiber scent carriers were compared to Aratex as traditionally used material for collecting of olfactory traces in criminology. Olfactory tests were carried out by dogs with special training and by mass spectrometer. Olfactory tests carried out by dogs clearly proved that nanofiber scent carriers were able to collect and preserve olfactory trace of lower concentration despite of their lower weight compared to samples of Aratex material. Olfactory tests carried out by mass spectrometer affirmed better olfactory properties of nanofiber scent carriers compared to Aratex, when nanofiber scent carriers were able to preserve 9 of 14 specific molecules characteristic for cigarette tobacco compared to Aratex that was able to preserve only 5 of 14 specific molecules characteristic for cigarette tobacco. The experiments with olfactory trace detection with materials with a comparable mass are in progress.
We tested collecting abilities of nanofibers prepared from polyvinyl alcohol and calcofluor (PVAC) for an odorological trace collection. Our study revealed that spectrum of odorological traces trapped on nanofibrous PVAC adsorbents, is more stable and reproducible compared to commonly used ARATEXTM. In addition, both PVA and PVAC nanofibers can adhere a large number of traces undetectable by ARATEX. Our results show that functionalization of commonly used adsorbent ARATEXTM with PVA and PVAC nanofibers can vastly increase the accuracy of trace collection and, thus, significantly improve forensic investigations.
Nanofibrous elastic material based on the blend of hydrophobic poly(ε-caprolactone) (PCL) and hydrophilic gelatin (Gel) reinforced with halloysite nanotubes (HNTs) was prepared by electrospinning process by respecting principles of "green chemistry" required for tissue engineering and drug delivery carriers. Three different kinds of HNTs with similar aspect ratio, but different length and inner diameter were examined to explain the effect of HNT concentration and geometry on a structure, morphology, chemical composition, mechanical properties and biocompatibility of nanostructured materials. Reinforcing effect of each type of HNTs has been confirmed up to 6 wt%. However, the highest improvement of mechanical properties was exhibited by addition just 0.5 wt% of HNTs. All HNT modified nanofibers have been confirmed as non-cytotoxic based on the interaction with mouse fibroblasts NIH-3T3 cells and therefore suitable for biomedical applications, e.g. as wound healing coverings with controlled drug delivery.
- MeSH
- buňky NIH 3T3 MeSH
- fibroblasty cytologie MeSH
- hojení ran * MeSH
- hydrolýza MeSH
- jíl MeSH
- mechanický stres MeSH
- myši MeSH
- nanotrubičky chemie ultrastruktura MeSH
- nanovlákna chemie ultrastruktura MeSH
- polyestery chemie MeSH
- proliferace buněk MeSH
- pružnost * MeSH
- silikáty hliníku chemie MeSH
- skot MeSH
- spektrometrie rentgenová emisní MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- viabilita buněk MeSH
- želatina chemie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
