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1.
Appl Surf Sci ; 321: 205-213, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25435600

RESUMO

The present study discusses the design, development and characterization of electrospun Tecoflex® EG 80A class of polyurethane nanofibers and the incorporation of multiwalled carbon nanotubes (MWCNTs) to these materials. Scanning electron microscopy results confirmed the presence of polymer nanofibers, which showed a decrease in fiber diameter at 0.5% wt. and 1% wt. MWCNTs loadings, while transmission electron microscopy showed evidence of the MWCNTs embedded within the polymer matrix. The fourier transform infrared spectroscopy and Raman spectroscopy were used to elucidate the polymer-MWCNTs intermolecular interactions, indicating that the C-N and N-H bonds in polyurethanes are responsible for the interactions with MWCNTs. Furthermore, tensile testing indicated an increase in the Young's modulus of the nanofibers as the MWCNTs concentration was increased. Finally, NIH 3T3 fibroblasts were seeded on the obtained nanofibers, demonstrating cell biocompatibility and proliferation. Therefore, the results indicate the successful formation of polyurethane nanofibers with enhanced mechanical properties, and demonstrate their biocompatibility, suggesting their potential application in biomedical areas.

2.
Tissue Eng Regen Med ; 21(5): 711-721, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38520636

RESUMO

BACKGROUND: In this study an approach was made to efficaciously synthesize gold enhanced titania nanorods by electrospinning. This study aims to address effects of gold enhanced titania nanorods on muscle precursor cells. Additionally, implant related microbial infections are prime cause of various disastrous diseases. So, there is predictable demand for synthesis of novel materials with multifunctional adaptability. METHODS: Herein, gold nanoparticles were attached on titania nanorods and described using many sophisticated procedures such as XRD, SEM, EDX and TEM. Antimicrobial studies were probed against Gram-negative Escherichia coli. C2C12 cell lines were exposed to various doses of as-prepared gold enhanced titania nanorods in order to test in vitro cytotoxicity and proliferation. Cell sustainability was assessed through Cell Counting Kit-8 assay at regular intervals. A phase-contrast microscope was used to examine morphology of exposed C2C12 cells and confocal laser scanning microscope was used to quantify cell viability. RESULTS: The findings indicate that titania nanorods enhanced with gold exhibit superior antimicrobial efficacy compared to pure titania. Furthermore, newly synthesized gold-enhanced titania nanorods illustrate that cell viability follows a time and concentration dependent pattern. CONCLUSION: Consequently, our study provides optimistic findings indicating that titania nanorods adorned with gold hold significant potential as foundational resource for developing forthcoming antimicrobial materials, suitable for applications both in medical and biomedical fields. This work also demonstrates that in addition to being extremely biocompatible, titania nanorods with gold embellishments may be used in a range of tissue engineering applications in very near future.


Assuntos
Proliferação de Células , Escherichia coli , Ouro , Nanotubos , Titânio , Ouro/química , Ouro/farmacologia , Titânio/farmacologia , Titânio/química , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Escherichia coli/efeitos dos fármacos , Nanotubos/química , Linhagem Celular , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Sobrevivência Celular/efeitos dos fármacos
3.
Appl Microbiol Biotechnol ; 97(10): 4523-31, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23306644

RESUMO

We explored electrospinning as a feasible and practicable mode for encapsulation and stabilization of Lactobacillus gasseri. The utilized nanocomposite was prepared using sol-gel composed of animate L. gasseri and inanimate PVA. The objective was to examine the ability of electrospinning method to protect functional properties of probiotic L. gasseri. The PVA was used as an encapsulation matrix as it is biocompatible and hydrophilic in nature thus facilitate an easy revival of bacteria. The characterization of as-spun bioproduct was done by energy-dispersive X-ray spectrometer, SEM, and TEM, whereas thermal behavior was analyzed by thermogravimetry. The viability was confirmed by traditional pour plate method and fluorescence microscopy. Furthermore, to test whether the functionality of L. gasseri was affected, the encapsulated L. gasseri were fed to mouse for colonization. Our results pointed out that encapsulated bacteria were viable for months, and their metabolism was not affected by immobilization; thus, they could be used in food engineering and trade.


Assuntos
Indústria Alimentícia , Lactobacillus/metabolismo , Álcool de Polivinil/metabolismo , Animais , Camundongos
4.
Appl Microbiol Biotechnol ; 97(12): 5545-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23467821

RESUMO

We report herein the synthesis and characterization of copper oxide quantum dots and their cytotoxic impact on mouse C2C12 cells. The utilized CuO quantum dots were prepared by the one-pot wet chemical method using copper acetate and hexamethylenetetramine as precursors. The physicochemical characterization of the synthesized CuO quantum dots was carried out using X-ray diffraction, energy-dispersive X-ray analysis, and transmission electron microscopy. To examine the in vitro cytotoxicity, C2C12 cell lines were treated with different concentrations of as-prepared quantum dots and the viability of cells was analyzed using Cell Counting Kit-8 assay at regular time intervals. The morphology of the treated C2C12 cells was observed under a phase-contrast microscope, whereas the quantification of cell viability was carried out via confocal laser scanning microscopy. To gain insight into the mechanism of cell death, we examined the effect of CuO quantum dots on the candidate genes such as caspases 3 and 7, which are key mediators of apoptotic events. In vitro investigations of the biological effect of CuO quantum dots have shown that it binds genomic DNA, decreases significantly the viability of cells in culture in a concentration (10-20 µg/mL) dependent manner, and inhibits mitochondrial caspases 3 and 7. To sum up, the elucidation of the pathways is to help in understanding CuO quantum dot-induced effects and evaluating CuO quantum dot-related hazards to human health.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 7/metabolismo , Cobre/toxicidade , Mioblastos/efeitos dos fármacos , Pontos Quânticos/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fenômenos Químicos , Camundongos , Microscopia Eletrônica de Transmissão , Microscopia de Contraste de Fase , Mioblastos/fisiologia , Espectrometria por Raios X , Difração de Raios X
5.
Int J Mol Sci ; 14(6): 11011-23, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23708101

RESUMO

In this study, we developed a one step process to synthesize nanogel containing silver nanoparticles involving electron beam irradiation. Water-soluble silver nitrate powder is dissolved in the distilled water and then poly(acrylic acid) (PAAc) and hexane are put into this silver nitrate solution. These samples are irradiated by an electron beam to make the PAAc nanogels containing silver nanoparticles (Ag/PAAc nanogels). The nanoparticles were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In addition, the particle size and zeta-potential were confirmed by a particle size analyzer (PSA). The antibacterial properties of the nanogels were evaluated by paper diffusion test. The Ag/PAAc nanogels had an antibacterial effect against Escherichia coli and Staphylococcus aureus. The nanogels also demonstrated a good healing effect against diabetic ulcer. The size of the Ag/PAAc nanogels decreased with increasing irradiation doses, and the absolute value of the zeta potential increased with increasing irradiation doses. Also, the Ag/PAAc nanogels exhibited good antibacterial activity against both Gram-negative and Gram-positive bacteria. In in vivo wound healing, the Ag/PAAc nanogels have a good healing effect.


Assuntos
Resinas Acrílicas/farmacologia , Anti-Infecciosos/farmacologia , Elétrons , Nanopartículas Metálicas/química , Polietilenoglicóis/farmacologia , Polietilenoimina/farmacologia , Prata/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Feminino , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Nanogéis , Tamanho da Partícula , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Staphylococcus aureus/efeitos dos fármacos , Eletricidade Estática , Cicatrização/efeitos dos fármacos
6.
Appl Microbiol Biotechnol ; 93(2): 743-51, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21761207

RESUMO

In this study, a biological evaluation of the antimicrobial activity of Zn-doped titania nanofibers was carried out using Escherichia coli ATCC 52922 (Gram negative) and Staphylococcus aureus ATCC 29231 (Gram positive) as model organisms. The utilized Zn-doped titania nanofibers were prepared by the electrospinning of a sol-gel composed of zinc nitrate, titanium isopropoxide, and polyvinyl acetate; the obtained electrospun nanofibers were vacuum dried at 80°C and then calcined at 600°C. The physicochemical properties of the synthesized nanofibers were determined by X-ray diffraction pattern, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron probe microanalysis, thermogravimetry, and transmission electron microscopy (TEM). The antibacterial activity and the acting mechanism of Zn-doped titania nanofibers against bacteria were investigated by calculation of minimum inhibitory concentration and analyzing the morphology of the bacterial cells following the treatment with nanofibers solution. Our investigations reveal that the lowest concentration of Zn-doped titania nanofibers solution inhibiting the growth of S. aureus ATCC 29231 and E. coli ATCC 52922 strains is found to be 0.4 and 1.6 µg/ml, respectively. Furthermore, Bio-TEM analysis demonstrated that the exposure of the selected microbial strains to the nanofibers led to disruption of the cell membranes and leakage of the cytoplasm. In conclusion, the combined results suggested doping promotes antimicrobial effect; synthesized nanofibers possess a very large surface-to-volume ratio and may damage the structure of the bacterial cell membrane, as well as depress the activity of the membranous enzymes which cause bacteria to die in due course.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Nanofibras , Staphylococcus aureus/efeitos dos fármacos , Titânio/farmacologia , Zinco/farmacologia , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Escherichia coli/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Staphylococcus aureus/ultraestrutura
7.
Appl Microbiol Biotechnol ; 95(1): 213-22, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22252266

RESUMO

Mn2O3 nanowires with diameter ~70 nm were synthesized by a simple hydrothermal method using Mn(II) nitrate as precursor. X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy techniques were employed to study structural features and chemical composition of the synthesized nanowires. A biological evaluation of the antimicrobial activity and cytotoxicity of Mn2O3 nanowires was carried out using Escherichia coli and mouse myoblast C2C12 cells as model organism and cell lines, respectively. The antibacterial activity and the acting mechanism of Mn2O3 nanowires were investigated by using growth inhibition studies and analyzing the morphology of the bacterial cells following the treatment with nanowires. These results suggest that the pH is critical factor affecting the morphology and production of the Mn2O3 nanowires. Method developed in the present study provided optimum production of Mn2O3 nanowires at pH ~ 9. The Mn2O3 nanowires showed significant antibacterial activity against the E. coli strain, and the lowest concentration of Mn2O3 nanowires solution inhibiting the growth of E. coli was found to be 12.5 µg/ml. TEM analysis demonstrated that the exposure of the selected microbial strains to the nanowires led to disruption of the cell membranes and leakage of the internal contents. Furthermore, the cytotoxicity results showed that the inhibition of C2C12 increases with the increase in concentration of Mn2O3 nanowires. Our results for the first time highlight the cytotoxic and bactericidal potential of Mn2O3 nanowires which can be utilized for various biomedical applications.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Compostos de Manganês , Mioblastos/efeitos dos fármacos , Nanofios/química , Óxidos , Animais , Biotecnologia , Linhagem Celular , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Óxidos/química , Óxidos/farmacologia , Óxidos/toxicidade
8.
J Microencapsul ; 28(4): 240-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21545315

RESUMO

The aim of this study was to modify the surfaces of magnetic iron oxide nanoparticles (IOPs) with gelatin in order to reduce cytotoxicity and enhance cellular uptake. The gelatin-coated IOPs were characterized in terms of their functionalization, size, surface charge, morphology and crystalline structure using Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), dynamic light scattering (DLS), transmission electron microscopy (BIO-TEM) and x-ray diffraction (XRD) analysis. The cytotoxicity of the gelatin-coated IOPs to human fibroblasts was assessed using an MTT-assay and was compared with uncoated IOPs. Similarly, the cellular uptake of the coated and uncoated IOPs was visualized using BIO-TEM and quantified using inductively coupled plasma spectroscopy (ICPS). As shown by the Fourier emission scanning electron microscopy (FE-SEM) and viability test, the massive uptake of uncoated IOPs lead to reduced viability. However, gelatin coating lead to increased viability and slow uptake without any visible distortion to the cell morphology.


Assuntos
Compostos Férricos/farmacologia , Gelatina/farmacologia , Nanopartículas , Sobrevivência Celular , Células Cultivadas , Sistemas de Liberação de Medicamentos/métodos , Compostos Férricos/química , Gelatina/química , Humanos , Tamanho da Partícula
9.
Nanomaterials (Basel) ; 11(11)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34835731

RESUMO

This study was performed to appraise the biocompatibility of polyhedral oligomeric silsesquioxane (POSS)-grafted polyurethane (PU) nanocomposites as potential materials for muscle tissue renewal. POSS nanoparticles demonstrate effectual nucleation and cause noteworthy enhancement in mechanical and thermal steadiness as well as biocompatibility of resultant composites. Electrospun, well-aligned, POSS-grafted PU nanofibers were prepared. Physicochemical investigation was conducted using several experimental techniques, including scanning electron microscopy, energy dispersive X-ray spectroscopy, electron probe microanalysis, Fourier transform infrared spectroscopy, and X-ray diffraction pattern. Adding POSS molecules to PU did not influence the processability and morphology of the nanocomposite; however, we observed an obvious mean reduction in fiber diameter, which amplified specific areas of the POSS-grafted PU. Prospective biomedical uses of nanocomposite were also appraised for myoblast cell differentiation in vitro. Little is known about C2C12 cellular responses to PU, and there is no information regarding their interaction with POSS-grafted PU. The antimicrobial potential, anchorage, proliferation, communication, and differentiation of C2C12 on PU and POSS-grafted PU were investigated in this study. In conclusion, preliminary nanocomposites depicted superior cell adhesion due to the elevated free energy of POSS molecules and anti-inflammatory potential. These nanofibers were non-hazardous, and, as such, biomimetic scaffolds show high potential for cellular studies and muscle regeneration.

10.
J Colloid Interface Sci ; 564: 65-76, 2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-31901835

RESUMO

In this study, mesoporous nickel cobaltite (NiCo2O4) nanorods as electrode materials for high-performance hybrid supercapacitor were fabricated onto Ni foam by a simple and cost effective oxalic acid (OA) assisted rapid co-precipitation method. The effects of different metal precursors (NCO-Nitrate, NCO-Chloride and NCO-Acetate) on the electrochemical capacitive properties were studied. FE-SEM analysis confirmed that all samples exhibited highly dense mesoporous NiCo2O4 nanorods vertically grown on the surface of Ni foam with excess accessible surfaces and unique sizes and morphologies. The resultant NiCo2O4 nanorod electrodes (for NCO-Nitrate, NCO-Chloride and NCO-Acetate) delivered the maximum specific capacitances of 790, 784, 776 F g-1 at the current density of 1 A g-1 with ultra-high capacitance retention of 82.27, 81.63 and 81.71% even at 20 A g-1 and excellent cyclic stability of 84.25, 83.33 and 83.24% capacitance retention at 5 A g-1 after 5000 cycles. The asymmetric supercapacitor (ASC) device was also sandwiched by using NCO-Nitrate as positive electrode and N-doped graphene hydrogel (NGH) as negative electrode. The fabricated ASC device delivered superior energy density (42.5 W h kg-1) at high power density (746.34 W kg-1) with excellent long cyclic stability (90% initial capacitance retention after 5000 cycles at 5 A g-1).

11.
Int J Pharm ; 365(1-2): 180-9, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-18790029

RESUMO

Magnetic iron oxide nanoparticles (IOPs) were coated with gelatin A and B and drug-loading efficiency was investigated using doxorubicin (DXR) as a model drug to evaluate their potential as a carrier system for magnetic drug targeting. Drug loading to coated IOPs was done using adsorption as well as desolvation/cross-linking techniques to understand their role. Drug loading by adsorption technique was done by incubating mixture of coated IOPs and drug in various conditions of pH, DXR-to-coated IOPs ratio, gelatin types and IOPs amounts. Drug loading by desolvation/cross-linking technique was done by adding acetone and glutaraldehyde (GTA) to the mixture of coated IOPs and DXR. The results indicated involvement of electrostatic interaction during loading of DXR-to-coated IOPs. Compared to adsorption technique, desolvation/cross-linking technique improved the efficiency of drug loading regardless of type of gelatin used for the coating. The DXR-loaded particles showed pH responsive drug release leading to accelerate release of drug at pH 4 compared to pH 7.4.


Assuntos
Doxorrubicina/administração & dosagem , Compostos Férricos/química , Gelatina/química , Magnetismo , Acetona/química , Animais , Antibióticos Antineoplásicos/administração & dosagem , Bovinos , Química Farmacêutica , Reagentes de Ligações Cruzadas/química , Sistemas de Liberação de Medicamentos , Glutaral/química , Concentração de Íons de Hidrogênio , Nanopartículas , Eletricidade Estática , Suínos , Tecnologia Farmacêutica
12.
Sci Rep ; 8(1): 7659, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29769569

RESUMO

There is growing interest in carbon fibre fabric reinforced polymer (CFRP) composites based on a thermoplastic matrix, which is easy to rapidly produce, repair or recycle. To expand the applications of thermoplastic CFRP composites, we propose a process for fabricating conductive CFRP composites with improved electrical and thermal conductivities using an in-situ polymerizable and thermoplastic cyclic butylene terephthalate oligomer matrix, which can induce good impregnation of carbon fibres and a high dispersion of nanocarbon fillers. Under optimal processing conditions, the surface resistivity below the order of 10+10 Ω/sq, which can enable electrostatic powder painting application for automotive outer panels, can be induced with a low nanofiller content of 1 wt%. Furthermore, CFRP composites containing 20 wt% graphene nanoplatelets (GNPs) were found to exhibit an excellent thermal conductivity of 13.7 W/m·K. Incorporating multi-walled carbon nanotubes into CFRP composites is more advantageous for improving electrical conductivity, whereas incorporating GNPs is more beneficial for enhancing thermal conductivity. It is possible to fabricate the developed thermoplastic CFRP composites within 2 min. The proposed composites have sufficient potential for use in automotive outer panels, engine blocks and other mechanical components that require conductive characteristics.

13.
Int J Biol Macromol ; 118(Pt A): 333-339, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29909030

RESUMO

ß-Glucan can provide excellent environment to apply to drug carrier due to its immunological and anti-inflammatory effect. Minocycline hydrochloride (MH) has excellent oral bioavailability pharmacological properties. Specifically, MH is effectively absorbed into the gingiva for periodontal disease treatment. In this study, we attempt to develop MH loaded ß-glucan hydrogel for periodontal disease treatment through radiation-crosslinking technique. In addition, MH loaded ß-glucan hydrogels were tested for their cytotoxicity and antibacterial activity. Finally, we conducted an in vivo study to demonstrate the potential to prevent the invasion of bacteria to treat periodontal disease. The gel content and compressive strength of the ß-glucan hydrogels increased as the ß-glucan content and the absorbed dose (up to 7 kGy) increased. For a radiation dose of 7 kGy, the gelation and the compressive strength of a 6 wt% ß-glucan hydrogel were approximately 92% and 270 kPa, respectively. As a drug, MH was consistently released from ß-glucan hydrogels, reaching 80% at approximately 90 min. Furthermore, the MH loaded ß-glucan hydrogels showed no cytotoxicity. The MH loaded ß-glucan hydrogels exhibited good antibacterial activity against Porphyromonas gingivalis. In addition, MH loaded ß-glucan hydrogel demonstrated the potential of a good capability to prevent the invasion of bacteria and to treat wounds.


Assuntos
Antibacterianos/química , Portadores de Fármacos/química , Hidrogéis/química , beta-Glucanas/química , Antibacterianos/uso terapêutico , Quitosana/química , Portadores de Fármacos/uso terapêutico , Humanos , Reologia
14.
Appl Biochem Biotechnol ; 182(2): 624-634, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27914018

RESUMO

Pristine ß-sitosterol or in combination with other phytosterols is utilized in an array of enriched commercial foods. Considering the presence of ß-sitosterol in different functional foods and its potential role in prevention and cure of neurodegenerative diseases, the aims of our investigation were to encapsulate ß-sitosterol in nanofibers and to estimate influence of ß-sitosterol on proliferation of fibroblasts. Electrospun nanofibers have widely been used as scaffolds to mimic natural extracellular matrix. Herein, our group for the first time establishes an innovative scaffold based on ß-sitosterol and polyurethane using electrospinning. ß-Sitosterol promotes epithelialization and possesses anti-oxidant and anti-inflammatory activities, whereas polyurethane, besides possessing biomedical uses, also enhances epithelial growth. We optimized the concentration (5%) of ß-sitosterol in polyurethane to obtain homogenous solution, which can be spun without difficulty for the synthesis of ß-sitosterol amalgamated scaffold. The resulted twisted nanofibers have been characterized via scanning electron microscopy and Fourier transform infrared spectroscopy. The viability of cells on twisted scaffold was examined using NIH 3T3 fibroblasts as model cell line. Incorporation of ß-sitosterol in polyurethane changed the structure and size of nanofibers, and the twisted scaffolds were non-cytotoxic. Thus, the twisted nanoribbons, which contain anti-inflammatory ß-sitosterol, can be utilized as a promising future material, which will help to ease inflammation and also aid in wound healing. In conclusion, the outcome of the preliminary research evidently points out the potential of twisted scaffold in biomedical applications.


Assuntos
Técnicas Eletroquímicas , Teste de Materiais , Nanofibras/química , Transição de Fase , Poliuretanos/química , Sitosteroides/química , Animais , Camundongos , Células NIH 3T3
15.
J Nanosci Nanotechnol ; 6(2): 510-3, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16573053

RESUMO

A simple method to deposit spherical gold nanoparticles on the surface of MgTiO3 ceramic nanofibers is presented. Electrospun MgTiO3/poly(vinyl acetate) (PVAc) hybrid nanofibers were calcined at 650 degrees C to obtain phase pure ceramic MgTiO3 nanofibers with 100-150 nm diameters. These ceramic nanofibers were immersed in an aqueous solution of HAuCl4 containing poly(vinyl alcohol) (PVA) as capping agent followed by photoreduction at 365 nm to get a novel Au-MgTiO3 nanocomposite. The formation of gold nanoparticles upon irradiation was confirmed by the appearance of a surface plasmon band (SPB) at 590 nm in the UV-visible absorption spectra. The surface morphology and elemental compositions were analyzed by the scanning electron microscope (SEM) equipped with energy dispersive X-ray (EDX), and transmission electron microscope (TEM). X-ray diffraction (XRD) and selected area diffraction (SAED) pattern in TEM revealed the crystallization of gold by exhibiting strong diffractions correspond to Au(111) and Au(200) crystalline planes in addition to the MgTiO3 diffraction.


Assuntos
Cerâmica , Ouro/química , Nanotecnologia , Óxidos/química , Titânio/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Raios X
16.
J Biomed Mater Res B Appl Biomater ; 78(2): 283-90, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16362963

RESUMO

The wettability of electrospun poly(epsilon-caprolactone) (PCL) mats was improved by co-electrospinning with poly(vinyl alcohol) (PVA), by double-spinneret electrospinning method. The improved hydrophilicity of the hybrid PCL/PVA mats was confirmed by water contact angle measurement. The in vitro cell attachment on the hydrophobic PCL and hydrophilically modified PCL/PVA mats was compared by culture studies using human prostate epithelial cells (HPECs). The stability of water-soluble PVA component in the electrospun PCL/PVA mats was checked by thermogravimetric analysis and intensity of fluorescence material after immersion in water for 7 days. The images from scanning electron microscopy, field emission scanning electron microscopy, and optical microscopy showed that the attachment and proliferation rate of HPECs were improved by introducing PVA into the electrospun PCL mats.


Assuntos
Materiais Revestidos Biocompatíveis , Células Epiteliais , Teste de Materiais , Poliésteres , Álcool de Polivinil , Próstata , Adesão Celular , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Células Epiteliais/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica de Varredura , Poliésteres/química , Álcool de Polivinil/química , Próstata/ultraestrutura , Molhabilidade
17.
J Biomed Mater Res B Appl Biomater ; 72(1): 117-24, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15389495

RESUMO

Electric field-driven fiber formation (electrospinning) is developing into a practical means for preparing novel porous filament with unusual structures and affordable mechanical properties. Polycaprolactone (PCL) was dissolved in solvent mixtures of methylene chloride/N,N-dimethyl formamide with ratios of 100/0, 75/25, and 50/50 (v/v) for electrospinning. The filament was formed by coagulation of the spinning solution following the well-known principle of phase separation in polymer solutions valid in other wet shaping processes. A strand of electrospun porous filament consisted of fibers ranging from 0.5 to 12 microm in diameter. To evaluate the feasibility of three-dimensional fabric as scaffold matrices, the plain weave, which is the simplest of the weaves and the most common, was prepared with porous PCL filament. The growth characteristics of MCF-7 mammary carcinoma cells in the woven fabrics showed the important role of matrix microstructure in proliferation. This study has shown that woven fabrics, consisting of porous filaments via electrospinning, may be suitable candidates as tissue engineering scaffolds.


Assuntos
Elétrons , Poliésteres/química , Engenharia Tecidual/instrumentação , Carcinoma/patologia , Carcinoma/ultraestrutura , Linhagem Celular Tumoral , Proliferação de Células , Forma Celular , Cristalização , Dimetilformamida , Humanos , Cinética , Mecânica , Cloreto de Metileno , Microscopia Eletrônica de Varredura , Soluções , Tensão Superficial , Viscosidade , Difração de Raios X
18.
J Biomed Mater Res B Appl Biomater ; 67(2): 675-9, 2003 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-14598393

RESUMO

Produced via electrospinning, polyurethane membrane, which has a unique property, has been of interest in medical fields. Electrospinning is a process by which nanofibers can be produced by an electrostatically driven jet of polymer solution. Electrospun fibers are collected in the form of membranes. The porous structured electrospun membrane is particularly important for its favorable properties: it exudates fluid from the wound, does not build up under the covering, and does not cause wound desiccation. The electrospun nanofibrous membrane shows controlled evaporative water loss, excellent oxygen permeability, and promoted fluid drainage ability, but still it can inhibit exogenous microorganism invasion because its pores are ultra-fine. Histological examination indicates that the rate of epithelialization is increased and the dermis becomes well organized if wounds are covered with electrospun nanofibrous membrane. This electrospun membrane has potential applications for wound dressing based upon its unique properties.


Assuntos
Bandagens/normas , Poliuretanos/uso terapêutico , Cicatrização , Animais , Líquidos Corporais , Células Epiteliais/patologia , Cobaias , Humanos , Masculino , Membranas Artificiais , Nanotecnologia , Oxigênio , Permeabilidade , Poliuretanos/síntese química , Porosidade , Ferimentos e Lesões/patologia
19.
Int J Nanomedicine ; 9: 891-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24611006

RESUMO

Recently, substantial interest has been generated in using electrospun biomimetic nanofibers of hybrids, particularly organic/inorganic, to engineer different tissues. The present work, for the first time, introduced a unique natural and synthetic hybrid micronanofiber wound dressing, composed of virgin olive oil/copper oxide nanocrystals and polyurethane (PU), developed via facile electrospinning. The as-spun organic/inorganic hybrid micronanofibers were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis, X-ray diffraction, electron probe microanalysis, and transmission electron microscopy. The interaction of cells with scaffold was studied by culturing NIH 3T3 fibroblasts on an as-spun hybrid micronanofibrous mat, and viability, proliferation, and growth were assessed. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay results and SEM observation showed that the hybrid micronanofibrous scaffold was noncytotoxic to fibroblast cell culture and was found to benefit cell attachment and proliferation. Hence our results suggest the potential utilization of as-spun micronanoscaffolds for tissue engineering. Copper oxide-olive oil/PU wound dressing may exert its positive beneficial effects at every stage during wound-healing progression, and these micronanofibers may serve diverse biomedical applications, such as tissue regeneration, damaged skin treatment, wound healing applications, etc. Conclusively, the fabricated olive oil-copper oxide/PU micronanofibers combine the benefits of virgin olive oil and copper oxide, and therefore hold great promise for biomedical applications in the near future.


Assuntos
Nanopartículas Metálicas/química , Nanofibras/química , Animais , Bandagens , Materiais Biocompatíveis/química , Adesão Celular , Cobre/química , Teste de Materiais , Nanopartículas Metálicas/ultraestrutura , Camundongos , Microscopia Eletrônica de Varredura , Células NIH 3T3 , Nanofibras/ultraestrutura , Nanomedicina , Azeite de Oliva , Óleos de Plantas/química , Poliuretanos/química , Pontos Quânticos/química , Engenharia Tecidual/métodos , Cicatrização
20.
J Colloid Interface Sci ; 397: 65-72, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23453708

RESUMO

Semiconductor nanoparticles incorporated highly aligned electrospun polyacrylonitrile (PAN) composite nanofibers were obtained via a simple, scalable and low-cost dip coating technique at room temperature. The resultant PAN nanofibers exhibited good incorporation of CdS, ZnS and CoS semiconductor nanoparticles. The detailed characterizations of these composite nanofibers were investigated. The incorporation of semiconductor nanoparticles on the surfaces of PAN nanofibers were confirmed by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy and X-ray diffraction analysis. The current-voltage (I-V) characteristics revealed that the electrical conductivity of these composite nanofibers were higher than that of the pristine PAN nanofibers. Overall, the feasibility of obtaining uniformly dispersed semiconductor nanoparticles on PAN nanofibers can be utilized for the realization of various nanotechnological device applications.

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