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1.
Front Bioeng Biotechnol ; 12: 1352717, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605986

RESUMO

This study developed a new burn wound dressing based on core-shell nanofibers that co-deliver antibiotic and antioxidant drugs. For this purpose, poly(ethylene oxide) (PEO)-chitosan (CS)/poly(D,L-lactide-co-glycolide) (PLGA) core-shell nanofibers were fabricated through co-axial electrospinning technique. Antibiotic levofloxacin (LEV) and antioxidant quercetin (QS) were incorporated into the core and shell parts of PEO-CS/PLGA nanofibers, respectively. The drugs could bond to the polymer chains through hydrogen bonding, leading to their steady release for 168 h. An in vitro drug release study showed a burst effect followed by sustained release of LEV and QS from the nanofibers due to the Fickian diffusion. The NIH 3T3 fibroblast cell viability of the drug loaded core-shell nanofibers was comparable to that in the control (tissue culture polystyrene) implying biocompatibility of the nanofibers and their cell supportive role. However, there was no significant difference in cell viability between the drug loaded and drug free core-shell nanofibers. According to in vivo experiments, PEO-CS-LEV/PLGA-QS core-shell nanofibers could accelerate the healing process of a burn wound compared to a sterile gauze. Thanks to the synergistic therapeutic effect of LEV and QS, a significantly higher wound closure rate was recorded for the drug loaded core-shell nanofibrous dressing than the drug free nanofibers and control. Conclusively, PEO-CS-LEV/PLGA-QS core-shell nanofibers were shown to be a promising wound healing material that could drive the healing cascade through local co-delivery of LEV and QS to burn wounds.

2.
Biomater Adv ; 159: 213821, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428121

RESUMO

Small joint reconstruction remains challenging and can lead to prosthesis-related complications, mainly due to the suboptimal performance of the silicone materials used and adverse host reactions. In this study, we developed hybrid artificial joints using three-dimensional printing (3D printing) for polycaprolactone (PCL) and incorporated electrospun nanofibers loaded with drugs and biomolecules for small joint reconstruction. We evaluated the mechanical properties of the degradable joints and the drug discharge patterns of the nanofibers. Empirical data revealed that the 3D-printed PCL joints exhibited good mechanical and fatigue properties. The drug-eluting nanofibers sustainedly released teicoplanin, ceftazidime, and ketorolac in vitro for over 30, 19, and 30 days, respectively. Furthermore, the nanofibers released high levels of bone morphogenetic protein-2 and connective tissue growth factors for over 30 days. An in vivo animal test demonstrated that nanofiber-loaded joints released high concentrations of antibiotics and analgesics in a rabbit model for 28 days. The animals in the drug-loaded degradable joint group showed greater activity counts than those in the surgery-only group. The experimental data suggest that degradable joints with sustained release of drugs and biomolecules may be utilized in small joint arthroplasty.


Assuntos
Nanofibras , Animais , Coelhos , Artroplastia , Impressão Tridimensional , Peptídeos e Proteínas de Sinalização Intercelular , Preparações Farmacêuticas
3.
Colloids Surf B Biointerfaces ; 237: 113864, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522283

RESUMO

Electrospun polymer scaffolds have gained prominence in biomedical applications, including tissue engineering, drug delivery, and wound dressings, due to their customizable properties. As the interplay between cells and materials assumes fundamental significance in biomaterials research, understanding the relationship between fiber properties and cell behaviour is imperative. Nevertheless, altering fiber properties introduces complexity by intertwining mechanical and surface chemistry effects, challenging the differentiation of their individual impacts on cell behaviour. Core-shell fibers present an appealing solution, enabling the control of mechanical properties of scaffolds, flexibility in material and drug selection, efficient encapsulation, strong protection of bioactive drugs against harsh environments, and controlled, prolonged drug release. This study addresses a key challenge in core-shell fiber design related to the blending effect between core and shell polymers. Two types of fibers, PMMA and core-shell PC-PMMA, were electrospun, and thorough analyses confirmed the desired core-shell structure in PC-PMMA fibers. Surface chemistry analysis revealed PC diffusion to the PMMA shell of the core-shell fiber during electrospinning, subsequently prompting an investigation of the fiber's surface potential. Conducting cellular studies on osteoblasts by super-resolution confocal microscopy provided insights into the direct influence of interfacial polymer blending and, consequently, altered fiber surface and mechanical properties on cell focal adhesion points, bridging the gap between material attributes and cell responses in core-shell fibers.


Assuntos
Polímeros , Polimetil Metacrilato , Polímeros/química , Polimetil Metacrilato/química , Adesões Focais , Engenharia Tecidual , Materiais Biocompatíveis/química , Alicerces Teciduais/química
4.
Biomaterials ; 306: 122507, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367300

RESUMO

Despite the significant progress made in recent years, clinical issues with small-diameter vascular grafts related to low mechanical strength, thrombosis, intimal hyperplasia, and insufficient endothelialization remain unresolved. This study aims to design and fabricate a core-shell fibrous small-diameter vascular graft by co-axial electrospinning process, which will mechanically and biologically meet the benchmarks for blood vessel replacement. The presented graft (PGHV) comprised polycaprolactone/gelatin (shell) loaded with heparin-VEGF and polycaprolactone (core). This study hypothesized that the shell structure of the fibers would allow rapid degradation to release heparin-VEGF, and the core would provide mechanical strength for long-term application. Physico-mechanical evaluation, in vitro biocompatibility, and hemocompatibility assays were performed to ensure safe in vivo applications. After 25 days, the PGHV group released 79.47 ± 1.54% of heparin and 86.25 ± 1.19% of VEGF, and degradation of the shell was observed but the core remained pristine. Both the control (PG) and PGHV groups demonstrated robust mechanical properties. The PGHV group showed excellent biocompatibility and hemocompatibility compared to the PG group. After four months of rat aorta implantation, PGHV exhibited smooth muscle cell regeneration and complete endothelialization with a patency rate of 100%. The novel core-shell structured graft could be pivotal in vascular tissue regeneration application.


Assuntos
Nanofibras , Enxerto Vascular , Ratos , Animais , Heparina/química , Fator A de Crescimento do Endotélio Vascular/química , Hiperplasia/prevenção & controle , Nanofibras/química , Prótese Vascular , Neointima/prevenção & controle , Poliésteres/química
5.
Small ; 20(3): e2305100, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37688343

RESUMO

Diabetic chronic wounds pose significant clinical challenges due to their characteristic features of impaired extracellular matrix (ECM) function, diminished angiogenesis, chronic inflammation, and increased susceptibility to infection. To tackle these challenges and provide a comprehensive therapeutic approach for diabetic wounds, the first coaxial electrospun nanocomposite membrane is developed that incorporates multifunctional copper peroxide nanoparticles (n-CuO2 ). The membrane's nanofiber possesses a unique "core/sheath" structure consisting of n-CuO2 +PVP (Polyvinylpyrrolidone)/PCL (Polycaprolactone) composite sheath and a PCL core. When exposed to the wound's moist environment, PVP within the sheath gradually disintegrates, releasing the embedded n-CuO2 . Under a weakly acidic microenvironment (typically diabetic and infected wounds), n-CuO2 decomposes to release H2 O2 and Cu2+ ions and subsequently produce ·OH through chemodynamic reactions. This enables the anti-bacterial activity mediated by reactive oxygen species (ROS), suppressing the inflammation while enhancing angiogenesis. At the same time, the dissolution of PVP unveils unique nano-grooved surface patterns on the nanofibers, providing desirable cell-guiding function required for accelerated skin regeneration. Through meticulous material selection and design, this study pioneers the development of functional nanocomposites for multi-modal wound therapy, which holds great promise in guiding the path to healing for diabetic wounds.


Assuntos
Diabetes Mellitus , Nanocompostos , Nanofibras , Humanos , Cicatrização , Pele/lesões , Nanocompostos/química , Nanofibras/química , Inflamação
6.
J Colloid Interface Sci ; 650(Pt B): 1371-1381, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37480652

RESUMO

Current design strategies for biomedical tissue scaffolds are focused on multifunctionality to provide beneficial microenvironments to support tissue growth. We have developed a simple yet effective approach to create core-shell fibers of poly(3-hydroxybuty-rate-co-3-hydroxyvalerate) (PHBV), which are homogenously covered with titanium dioxide (TiO2) nanoparticles. Unlike the blend process, co-axial electrospinning enabled the uniform distribution of nanoparticles without the formation of large aggregates. We observed 5 orders of magnitude reduction in Escherichia coli survival after contact with electrospun scaffolds compared to the non-material control. In addition, our hybrid cores-shell structure supported significantly higher osteoblast proliferation after 7 days of cell culture and profound generation of 3D networked collagen fibers after 14 days. The organic-inorganic composite scaffold produced in this study demonstrates a unique combination of antibacterial properties and increased bone regeneration properties. In summary, the multifunctionality of the presented core-shell cPHBV+sTiO2 scaffolds shows great promise for biomedical applications.


Assuntos
Nanopartículas , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual , Polímeros/farmacologia , Poliésteres/química , Antibacterianos/farmacologia , Colágeno , Proliferação de Células , Nanopartículas/química
7.
Nanotechnology ; 34(44)2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37524074

RESUMO

Co-axially electrospun, magnetic Fe3O4@carbon (Fe3O4@C) nanofibers comprising Fe3O4particles in the core and carbon in the shell have been fabricated and their performances as magnetic material have been studied. The electrospun Fe3O4@C nanofibers have been characterized with x-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscope, x-ray photoelectron spectroscope (XPS), and superconducting quantum interference device magnetometer. The structural and microstructural analysis has given a brief idea about the pure Fe3O4and C phase formation and also the existence of smooth and continuous morphology of Fe3O4@C nanofibers. It has been shown that there exist two different oxidation states of Fe in the XPS spectrum. The magnetization hysteresis loop has been observed at low temperatures (5 K, 100 K) as well as at room temperature (300 K) which gives different magnetic parameters. Temperature dependent magnetic measurements (from 5 to 300 K) suggest the existence of Verwey transition for lower percentage of iron oxide content.

8.
J Biomater Sci Polym Ed ; 34(9): 1217-1236, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36576335

RESUMO

Nanofibrous scaffolds with core-shell structures can deliver bioactive agents, augment mechanical properties, provide a high surface area to volume ratio, and most importantly mimic the structure of extracellular matrix (ECM) which enables to maintain of a moist environment, elimination of excess exudates and provide antibacterial properties to impede infections. This study has developed PVA, licorice, and collagen (PLC) based hybrid bio-nano scaffold by co-axial electrospinning technique for enhancing wound closure. The core layer was made by PVA & licorice extract and shell layer was created by collagen & licorice extract solution. The morphology, moisture management properties, presence of constituent polymer, thermal behavior, and mechanical properties of the developed samples were characterized by FE-SEM, moisture management tester (MMT), FT/IR, TGA, tensile testing machine. Furthermore, in vitro antibacterial assay was conducted by Kirby-Bauer disk diffusion method for investigating antibacterial properties and an in-vivo wound healing assessment was employed by observing the wound healing. Then FE-SEM images showed the lowest and highest average diameters 119 nm and 154 nm respectively, FT/IR spectra ensured the presence of all materials in the sample. Furthermore, the moisture management test result demonstrated slow absorbing and slow drying scaffolds which emphasized the eligibility of the sample to be an ideal candidate for wound healing. Moreover, the minimum and maximum zones of inhibition (ZOI) were found 7 mm and 8 mm against the bacteria Staphylococcus aureus. Finally, an in vivo wound healing assessment revealed a better healing performance of the developed samples after 10 days.


Assuntos
Quitosana , Glycyrrhiza , Nanofibras , Quitosana/química , Cicatrização , Colágeno , Antibacterianos/farmacologia , Antibacterianos/química , Nanofibras/química , Álcool de Polivinil/química
9.
Nanomaterials (Basel) ; 12(8)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35457992

RESUMO

Recycling biomass waste into functional materials has attracted much attention, and a rational structural design can make more effective use of each component. In our previous work, the fabrication of electrospun cellulose-acetate (CA)/chitosan (CS) adsorbents for humic-acid (HA) removal guided by the intermolecular interaction mechanism was demonstrated. Herein, a core-sheath structure was designed via one-step co-axial electrospinning, where a mixture of CS and CA was employed as the sheath layer to efficiently adsorb HA, and cellulose nanocrystals (CNCs) derived from waste cotton fabrics were incorporated into the CA core as load-bearing components. Compared to the non-layered electrospun CS/CA fibers, all the CS/CA-CNC fibers with a core-sheath structure exhibited smaller diameters, greater homogeneity, and significantly improved mechanical strength. Meanwhile, their maximum adsorption capacities towards HA had no significant differences. Even after the complete hydrolysis of CA into cellulose, the electrospun fibers maintained the fibrous structures and showed a higher tensile strength while exhibiting an acceptable adsorption capacity towards HA. Therefore, this work demonstrates the importance of rational design in the efficient preparation of functional materials and the feasibility of using electrospun core-sheath fibers derived from biomass wastes for the removal of water contaminants.

10.
Pharmaceutics ; 13(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34683958

RESUMO

The present study describes the use of two taste-masking polymers to fabricate a formulation of chlorpheniramine maleate for paediatric administration. Co-axial electrospinning was utilized to create layered nanofibres; the two polymers, Eudragit® E PO and Kollicoat® Smartseal, were alternated between the core and the shell of the system in order to identify the optimum taste-masked formulation. The drug was loaded in the core on all occasions. It was found that the formulation with Kollicoat® Smartseal in the core with the drug, and Eudragit® E PO in the shell showed the most effective taste-masking compared to the other formulations. These fibres were in the nano-range and had smooth morphology as verified by scanning electron microscopy. Solid-state characterization and thermal analysis confirmed that amorphous solid dispersions were formed upon electrospinning. The Insent E-tongue was used to assess the taste-masking efficiency of the samples, and it was found that this formulation was undetectable by the bitter sensor, indicating successful taste-masking compared to the raw version of the drug. The E-tongue also confirmed the drug's bitterness threshold as compared to quinine HCl dihydrate, a parameter that is useful for formulation design and taste-masking planning.

11.
Polymers (Basel) ; 12(7)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635276

RESUMO

Mats of polyvinyl alcohol (PVA) core-shell nanofibers were produced using coaxial electrospinning in the presence of a thiosemicarbazone (TSC) N4-(S)-1-phenylethyl)-2-(pyridin-2-yl-ethylidene)hydrazine-1-carbothioamide (HapyTSCmB). Monolithic fibers with 0% or 5% TSC and core-shell fibers with 10% TSC in the spinning solution were studied to compare stability and release rates. SEM showed the formation of uniform, bead-free, cylindrical, and smooth fibers. NMR spectroscopy and thermal analysis (TG/DTA) gave proof for the chemical integrity of the TSC in the fiber mats after the electrospinning process. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy showed no TSC on the surface of the PVA/TSC-PVA fibers confirming the core-shell character. The TSC release profiles of the fibers as studied using UV-vis absorption spectroscopy showed a slower release from the PVA/TSC-PVA core-shell structure compared with the monolithic PVA/TSC fibers as well as lower cumulative release percentage (17%). Out of several release models, the Korsmeyer-Peppas model gave the best fit to the experimental data. The main release phase can be described with a Fick-type diffusion mechanism. Antibacterial properties were tested against the Gram-positive Staphylococcus aureus bacterium and gave a minimal inhibitory concentration of 12.5 µg/mL. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT)-based cytotoxicity experiments showed that the cell viability of fibroblast at different contents of TSC was slightly decreased from 1.5% up to 3.5% when compared to control cells.

12.
J Nanobiotechnology ; 18(1): 51, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188479

RESUMO

The state-of-the-art hernia meshes, used in hospitals for hernia repair, are predominantly polymeric textile-based constructs that present high mechanical strength, but lack antimicrobial properties. Consequently, preventing bacterial colonization of implanted prosthetic meshes is of major clinical relevance for patients undergoing hernia repair. In this study, the co-axial electrospinning technique was investigated for the development of a novel mechanically stable structure incorporating dual drug release antimicrobial action. Core/shell structured nanofibers were developed, consisting of Nylon-6 in the core, to provide the appropriate mechanical stability, and Chitosan/Polyethylene oxide in the shell to provide bacteriostatic action. The core/shell structure consisted of a binary antimicrobial system incorporating 5-chloro-8-quinolinol in the chitosan shell, with the sustained release of Poly(hexanide) from the Nylon-6 core of the fibers. Homogeneous nanofibers with a "beads-in-fiber" architecture were observed by TEM, and validated by FTIR and XPS. The composite nanofibrous meshes significantly advance the stress-strain responses in comparison to the counterpart single-polymer electrospun meshes. The antimicrobial effectiveness was evaluated in vitro against two of the most commonly occurring pathogenic bacteria; S. aureus and P. aeruginosa, in surgical site infections. This study illustrates how the tailoring of core/shell nanofibers can be of interest for the development of active antimicrobial surfaces.


Assuntos
Antibacterianos/farmacologia , Caprolactama/análogos & derivados , Caprolactama/farmacologia , Quitosana/farmacologia , Nanofibras/química , Polímeros/farmacologia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Antibacterianos/química , Quitosana/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Cinética , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Polímeros/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Telas Cirúrgicas
13.
Int J Nanomedicine ; 15: 913-925, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103946

RESUMO

INTRODUCTION: Masquelet proposed a new solution for the healing of segmental bone defects, thus minimizing the disadvantages associated with traditional bone grafting. However, a major factor leading to the failure of this technique pertains to be the residual infection. Accordingly, we developed an antibiotic- and osteo-inductive agent-loaded composite scaffold to solve this problem. METHODS: A mesh-like polycaprolactone scaffold was prepared using a lab-exploited solution-type three-dimensional printer, and hybrid sheath-core structured poly(lactic-co-glycolic-acid) nanofibers were fabricated using co-axial electrospinning technology. Vancomycin, ceftazidime, and bone morphological protein (BMP)-2 were employed. The in vitro and in vivo (rabbit fracture model) release patterns of applied agents from the composite scaffold were investigated. RESULTS: The results revealed that the drug-eluting composite scaffold enabled the sustainable release of the medications for at least 30 days in vitro. Animal tests demonstrated that a high concentration of medications was maintained. Abundant growth factors were induced within the bioactive membrane stimulated by the applied scaffold. Finally, satisfactory bone healing potential was observed on radiological examination and biomechanical evaluation. DISCUSSION: The developed composite scaffold may facilitate bone healing by inducing bioactive membrane formation and yielding high concentrations of antibiotics and BMP-2 during the Masquelet procedure.


Assuntos
Antibacterianos/administração & dosagem , Regeneração Óssea/fisiologia , Fêmur/cirurgia , Nanofibras/química , Procedimentos de Cirurgia Plástica/métodos , Animais , Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Ceftazidima/química , Ceftazidima/farmacologia , Nanofibras/administração & dosagem , Nanofibras/uso terapêutico , Osteotomia/métodos , Poliésteres/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Impressão Tridimensional , Coelhos , Procedimentos de Cirurgia Plástica/efeitos adversos , Infecção da Ferida Cirúrgica/prevenção & controle , Alicerces Teciduais , Vancomicina/química , Vancomicina/farmacologia
14.
Int J Biol Macromol ; 151: 186-192, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32070734

RESUMO

Endothelization of a tissue-engineered substrate is important for its application as an artificial vascular graft. Despite recent advancements in artificial graft fabrication, a graft of <5 mm is difficult to fabricate owing to insufficient endothelization that results in thrombosis after transplantation. We aimed to perform a co-culture of adipose-derived mesenchymal stem cells (MSCs) with human umbilical vein endothelial cells (HUVECs) on antithrombogenic polycaprolactone (PCL)/heparin-gelatin co-spun nanofibers to evaluate the role of co-culturing in promoting quick endothelization of vascular substrates without surface modification by growth factors or other ECM proteins that trigger the endothelization process. Using a co-axial electrospinning technique, we attempted to fabricate our scaffold balancing between mechanical properties and biocompatibility. Antithrombogenic characteristics were then imparted to the fabricated nanofiber substrate by grafting of heparin. Finally, we performed a co-culture of MSCs and HUVECs on the fabricated co-spun nanofiber substrate to obtain proper endothelization of our material under the in-vitro culture. Staining for CD-31 at seven days of culture revealed enhanced CD-31 expression under the co-culture condition; actin staining revealed healthy cobblestone HUVEC morphology, suggesting that MSCs can aid in proper endothelization. Hence, we conclude that co-culture is effective for quick endothelization of vascular substrates.


Assuntos
Gelatina , Heparina , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/citologia , Nanofibras , Poliésteres , Alicerces Teciduais/química , Diferenciação Celular , Técnicas de Cocultura , Citoesqueleto/química , Citoesqueleto/metabolismo , Endotélio , Imunofluorescência , Gelatina/química , Heparina/química , Humanos , Nanofibras/química , Nanofibras/ultraestrutura , Poliésteres/química , Engenharia Tecidual
15.
Nanomedicine ; 23: 102090, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31493556

RESUMO

Mimicking the ultrastructural morphology of the meniscus with nanofiber scaffolds, coupled with controlled growth-factor delivery to the appropriate cells, can help engineer tissue with the potential to grow, mature, and regenerate after in vivo implantation. We electrospun nanofibers encapsulating platelet-derived growth factor (PDGF-BB), which is a potent mitogen and chemoattractant in a core of serum albumin contained within a shell of polylactic acid. We controlled the local PDGF-BB release by adding water-soluble polyethylene glycol to the polylactic acid shell to serve as a porogen. The novel core-shell nanofibers generated 3D scaffolds with an interconnected macroporous structure, with appropriate mechanical properties and with high cell compatibility. Incorporating PDGF-BB increased cell viability, proliferation, and infiltration, and upregulated key genes involved in meniscal extracellular matrix synthesis in human meniscal and synovial cells. Our results support proof of concept that these core-shell nanofibers can create a cell-favorable nanoenvironment and can serve as a system for sustained release of bioactive factors.


Assuntos
Becaplermina , Menisco/fisiologia , Nanofibras/química , Regeneração/efeitos dos fármacos , Alicerces Teciduais/química , Adolescente , Adulto , Becaplermina/química , Becaplermina/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Feminino , Humanos , Masculino , Poliésteres/química , Poliésteres/farmacologia , Engenharia Tecidual
16.
Mar Drugs ; 17(1)2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30621270

RESUMO

Nanofibrous structures mimicking the native extracellular matrix have attracted considerable attention for biomedical applications. The present study aims to design and produce drug-eluting core-shell fibrous scaffolds for wound healing and skin tissue engineering. Aloe vera extracts were encapsulated inside polymer fibers containing chitosan, polycaprolactone, and keratin using the co-axial electrospinning technique. Electron microscopic studies show that continuous and uniform fibers with an average diameter of 209 ± 47 nm were successfully fabricated. The fibers have a core-shell structure with a shell thickness of about 90 nm, as confirmed by transmission electron microscopy. By employing Fourier-transform infrared spectroscopy, the characteristic peaks of Aloe vera were detected, which indicate successful incorporation of this natural herb into the polymeric fibers. Tensile testing and hydrophilicity measurements indicated an ultimate strength of 5.3 MPa (elongation of 0.63%) and water contact angle of 89°. In-vitro biological assay revealed increased cellular growth and adhesion with the presence of Aloe vera without any cytotoxic effects. The prepared core-shell fibrous mats containing medical herbs have a great potential for wound healing applications.


Assuntos
Plantas Medicinais/química , Pele/efeitos dos fármacos , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacos , Aloe/química , Quitosana/química , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura/métodos , Nanofibras/química , Poliésteres/química , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Resistência à Tração/efeitos dos fármacos , Engenharia Tecidual/métodos
17.
Carbohydr Polym ; 193: 316-325, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29773387

RESUMO

This represents the first systematic study where levan polysaccharide was used to fabricate fibrous matrices by co-axial and single-needle electrospinning techniques. For this, hydrolyzed (hHL) and sulfated hydrolyzed (ShHL) Halomonas levan were chemically synthesized and used together with polycaprolactone (PCL) and polyethyleneoxide (PEO) for the spinning process. In co-axially spun matrices, ultimate tensile strength (UTS) were found to increase with increasing ShHL concentration and elongation at break of PCL + ShHL matrices increased up to ten-fold when compared to PCL matrices. Similarly, in single-needle spun matrices, higher elongation at break values were obtained by blending HL and ShHL with PEO pointing to the effective energy absorbing features. Dense and fine fibers were characterized by FTIR and SEM. Cell viability and fluorescence imaging of L929 fibroblasts and HUVECs as well as heparin mimetic activity of the matrices pointed to their high potential to be used in decreasing neointimal proliferation and thrombogenicity of grafts and prosthesis.

18.
PeerJ ; 5: e4125, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29302386

RESUMO

With the rapid advancement of regenerative medicine technologies, there is an urgent need for the development of new, cell-friendly techniques for obtaining nanofibers-the raw material for an artificial extracellular matrix production. We investigated the structure and properties of PCL10 nanofibers, PCL5/PCL10 core-shell type nanofibers, as well as PCL5/PCLAg nanofibres prepared by electrospinning. For the production of the fiber variants, a 5-10% solution of polycaprolactone (PCL) (Mw = 70,000-90,000), dissolved in a mixture of formic acid and acetic acid at a ratio of 70:30 m/m was used. In order to obtain fibers containing PCLAg 1% of silver nanoparticles was added. The electrospin was conducted using the above-described solutions at the electrostatic field. The subsequent bio-analysis shows that synthesis of core-shell nanofibers PCL5/PCL10, and the silver-doped variant nanofiber core shell PCL5/PCLAg, by using organic acids as solvents, is a robust technique. Furthermore, the incorporation of silver nanoparticles into PCL5/PCLAg makes such nanofibers toxic to model microbes without compromising its biocompatibility. Nanofibers obtained such way may then be used in regenerative medicine, for the preparation of extracellular scaffolds: (i) for controlled bone regeneration due to the long decay time of the PCL, (ii) as bioscaffolds for generation of other types of artificial tissues, (iii) and as carriers of nanocapsules for local drug delivery. Furthermore, the used solvents are significantly less toxic than the solvents for polycaprolactone currently commonly used in electrospin, like for example chloroform (CHCl3), methanol (CH3OH), dimethylformamide (C3H7NO) or tetrahydrofuran (C4H8O), hence the presented here electrospin technique may allow for the production of multilayer nanofibres more suitable for the use in medical field.

19.
J Biomater Appl ; 31(5): 784-796, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27698255

RESUMO

Stent insertion and chemical agents of ethylene diamine tetraacetic acid and sodium cholate for dissolving common bile duct stone diseases through extra biliary tract infusion have been believed a relatively effective therapeutics for the clinical symptom. Core-shell nanofibers produced by co-axial electrospinning to deliver chemical drugs, biomacromolecules, genes and even cells have been reported for various advanced drug delivery system and tissue engineering applications. In the present study, poly (lactide-co-ɛ-caprolactone) (PLCL) core-shell nanofiber-coated film of stent, loaded with ethylene diamine tetraacetic acid and sodium cholate in core layer, was fabricated by co-axial electrospinning for treating gallstone disease. Image of laser scanning confocal microscopy and transmission electron microscopy demonstrated core-shell structure of drug-loaded nanofiber. Fourier transform infrared spectra and the thermogravimetric analysis proved ethylene diamine tetraacetic acid and sodium cholate to be successfully loaded in nanofibers. Morphology of nanofibers after a period of degradation still keeps good shape. Drugs can continuously release for around five days, which was proved significant effectiveness for dissolving gallstone. Besides, unobvious cytotoxicity was exhibited from MTT results and cell kept good morphology in vitro research. The present coated stent showed a bright prospect for dissolving the biliary stone.


Assuntos
Ácido Acético/administração & dosagem , Materiais Revestidos Biocompatíveis/administração & dosagem , Implantes de Medicamento/administração & dosagem , Stents Farmacológicos , Cálculos Biliares/química , Nanofibras/química , Colato de Sódio/administração & dosagem , Materiais Revestidos Biocompatíveis/química , Combinação de Medicamentos , Implantes de Medicamento/síntese química , Desenho de Equipamento , Análise de Falha de Equipamento , Cálculos Biliares/tratamento farmacológico , Cálculos Biliares/patologia , Humanos , Teste de Materiais , Metais/química , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Nanofibras/ultraestrutura , Colato de Sódio/química , Resultado do Tratamento
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