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1.
J Biomed Mater Res A ; 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33738960

RESUMO

Here, engineered cartilage-like scaffold using an extracellular matrix (ECM) from sturgeon fish cartilage provided a chondroinductive environment to stimulate cartilaginous matrix synthesis in human adipose stem cells (hASCs). Three dimensional porous and degradable fish cartilage ECM-derived scaffold (FCS) was produced using a protocol containing chemical decellularization, enzymatic solubilization, freeze-drying and EDC-crosslinking treatments and the effect of different ECM concentrations (10, 20, 30, and 40 mg/ml) on prepared scaffolds was investigated through physical, mechanical and biological analysis. The histological and scanning electron microscopy analysis revealed the elimination of the cell fragments and a 3-D interconnected porous structure, respectively. Cell viability assay displayed no cytotoxic effects. The prepared porous constructs of fish cartilage ECM were seeded with hASCs for 21 days and compared to collagen (Col) and collagen-10% hyaluronic acid (Col-HA) scaffolds. Cell culture results evidenced that the fabricated scaffolds could provide a proper 3-D structure to support the adhesion, proliferation and chondrogenic differentiation of hASCs considering the synthesis of specific proteins of cartilage, collagen type II (Col II) and aggrecan (ACAN). Based on the results of the present study, it can be concluded that the porous scaffold derived from fish cartilage ECM possesses an excellent potential for cartilage tissue engineering.

2.
Prog Biomater ; 9(4): 175-185, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33070246

RESUMO

APEGylatedcurcumin (PCU) loaded electrospuns based on poly(ε-caprolactone) (PCL) andpolyvinyl alcohol (PVA) were fabricated for wound dressing applications. The main reason for this wound dressing design is antibacterialactivity enhancement, and wound exudates management. PEGylation increases curcuminsantibacterial properties and PVA can help exudates management. For optimal wound dressing, first, response surface methodology (RSM) was applied to optimize the electrospinning parameters to achieve appropriate nanofibrous mats. Then a three-layer electrospun was designed by considering the water absorbability, PCU release profile as well as antibacterial and biocompatibility of the final wound dressing. The burst release in controlled release systems could be evaluated for prevention of the higher initial drug release and control the effective life time. The PCU release results illustrated that the bead knot plays a positive role in controlling the release profile andby increase in the number of beads per unit area from 3000 to 9000 mm-2,the PCU burst release will be reduced; Also in vitro studies show that optimized three-layer dressing based on PCL/PVA/PCU can support water vapour transmission rate in optimal range and also absorb more than three times exudates in comparison with mono-layerdressing. Antibacterial tests show that the electrospun wound dressing containing 5% PCU exhibits100% antibacterial activityas well as cell viability level within an acceptable range.

3.
Int J Pharm ; 577: 119037, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31953081

RESUMO

Spinal Cord Injury (SCI) is one of the leading causes of physical disability. In this study, spherical PLGA nanoparticles (NPs) containing ChABC enzyme were manufactured and fully characterized for SCI therapy. The NPs were used in the rat's contused spinal cord to assess the functional improvement and scar digestion. Twenty-three adult male Wistar rats (275 ± 25 g) were assigned into four groups of control, sham, blank-treated particle, and ChABC-treated particle. Throughout the survey, the BBB scores were obtained for all the groups. Finally, the injured sections of animals were dissected, and histological studies were conducted using Luxol fast blue and Bielschowsky. The biocompatibility and non-toxicity effects of the NPs on olfactory ensheathing cells (OECs) were confirmed by the MTT test. The flow-cytometry revealed the purity of cultured OECs with p75+/GFAP+ at around 87.9 ± 2.4%. Animals in the control and the blank-treated groups exhibited significantly lower BBB scores compared with the ChABC-treated particle group. Histological results confirmed the induced contusion models in the injured site. Myelin was observed in the treated groups, especially when the ChABC-loaded nanoparticles were utilized. The immunohistochemistry results indicated the scar glial degradation in animals treated by the ChABC-loaded particles. According to this study, the loaded particles can potentially serve as a suitable candidate for spinal cord repair, functional recovery and axonal regeneration.

4.
Int J Biol Macromol ; 147: 946-953, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31765746

RESUMO

Scaffolds that are used for neural tissue engineering are fabricated to mimic the extracellular matrix. In this paper, we have fabricated polyvinyl alcohol/sulfated alginate (PVA/SA) nanofibers with different concentrations (10, 20 and 30 wt%) of sulfated alginate by electrospinning technique. The average fibers diameters of 169-488 nm were achieved by electrospinning of polymers blend (PVA/SA). The results of the MTT assay and scanning electron microscopy showed that PVA/sulfated alginate nanofibrous scaffold with 30 wt% SA provided more desirable surface attachment of C6, Schwann cells (SCs) and human bone marrow mesenchymal stem cells (hBMSCs). RT-PCR and immunocytochemistry for MAP-2 marker were conducted to confirm the neural-differentiation of hBMSCs. The expression of MAP-2 confirmed neural differentiation for up to 14 days. Our results showed that PVA/SA nanofibrous scaffold with 30 wt% SA is a suitable substrate for mesenchymal stem cells growth and is capable of inducing neuronal differentiation.


Assuntos
Alginatos/química , Células da Medula Óssea/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Nanofibras/química , Neurônios/metabolismo , Álcool de Polivinil/química , Tecidos Suporte/química , Células da Medula Óssea/citologia , Linhagem Celular , Humanos , Células-Tronco Mesenquimais/citologia , Neurônios/citologia
5.
Int J Pharm ; 575: 118947, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31837404

RESUMO

A series of biodegradable amphiphilic-block segmented polyurethanes (SPUs) are designed and synthesized based on di-block and tri-block macrodiols of polycaprolactone (PCL) and polyethylene glycol (PEG). Curcumin, as a model herbal antibacterial agent, is used due to its effective inhibitory action against Gram-positive and Gram-negative bacteria. Curcumin-loaded nanofibers, with 400-900 nm diameter range, have been prepared by electrospinning of SPUs. The synthesized SPUs can be used for wound dressing applications due to their excellent mechanical properties and higher hydrophilicity in comparison to PCL-based polyurethane. The elongation-at-break of tri-block SPU with PEG-PCL-PEG soft segments is 350% when produced as an electrospun mat and that for film is 1500%. In vitro release of curcumin, examined by UV-Vis spectroscopy, shows a steady release during 18 days. The inclusion of PEG chains in the soft segment increases the hydrophilicity and biodegradation rate of the electrospun mats compared to a PCL-based polyurethane, which eventually results in a higher curcumin release rate. The antibacterial activity of 50 mg of 10% curcumin-loaded SPU nanofibers is about 100% and 93% against Escherichia coli (E. coli ATCC: 25922) and Staphylococcus aureus (S. aureus ATCC: 6538), respectively. Nontoxic behavior of the scaffolds is evaluated through MTT assay against L929 mouse fibroblast cells. The results show that the synthesized SPUs can be used as a nanoscale sustained release carrier. The SPU with PEG-PCL-PEG soft segments is an excellent candidate for wound dressing in tissues undergoing large deformations during normal activities.


Assuntos
Antibacterianos/farmacologia , Bandagens , Curcumina/farmacologia , Nanofibras/química , Tecidos Suporte/química , Animais , Antibacterianos/administração & dosagem , Curcumina/administração & dosagem , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Camundongos , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Poliuretanos/química , Porosidade , Staphylococcus aureus/efeitos dos fármacos
6.
ACS Appl Mater Interfaces ; 11(39): 35525-35539, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31490646

RESUMO

A novel poly(urethane-urea) (PUU) based on poly(glycolide-co-ε-caprolactone) macro-diol with tunable mechanical properties and biodegradation behavior is reported for corneal stromal tissue regeneration. Zn-Al layered double hydroxide (LDH) nanoparticles were synthesized and loaded with vitamin C (VC, VC-LDH) and dispersed in the PUU to control VC release in the cell culturing medium. To mimic the corneal stromal EC, scaffolds of the PUU and its nanocomposites with VC-LDH (PUU-LDH and PUU-VC-LDH) were fabricated via electrospinning. Average diameters of the aligned nanofibers were recorded as 325 ± 168, 343 ± 171, and 414 ± 275 nm for the PUU, PUU-LDH, and PUU-VC-LDH scaffolds, respectively. Results of hydrophilicity and mechanical properties measurements showed increased hydrophobicity and reduced tensile strength and elongation at break upon addition of nanoparticles to the PUU scaffold. VC release studies represented that intercalation of the drug in Zn-Al-LDH controlled the burst release and extended the release period from a few hours to 5 days. Viability and proliferation of stromal keratocyte cells on the scaffolds were investigated via AlamarBlue assay. After 24 h, the cells showed similar viability on the scaffolds and the control. After 1 week, the cells showed some degree of proliferation on the scaffolds, with the highest value recorded for PUU-VC-LDH. SEM images of the scaffolds after 24 h and 1 week confirmed good penetration and attachment of keratocytes on all the scaffolds and the cells oriented with the direction of nanofibers. After 1 week, the PUU-VC-LDH scaffold was fully covered by the cells. Immunocytochemistry assay (ICC) was performed to investigate secretion of vimentin protein, ALDH3A1, and α-SMA by the cells. After 24h and 1 week, remarkably higher levels of vimentin and ALDH3A1 and lower level of α-SMA were secreted by keratocytes on PUU-VC-LDH compared to those on the PUU and PUU-LDH scaffolds and the control. Our results suggest that the aligned PUU-VC-LDH is a promising candidate for corneal stromal tissue engineering due to the presence of zinc and vitamin C.


Assuntos
Ácido Ascórbico , Proliferação de Células/efeitos dos fármacos , Córnea/metabolismo , Queratinócitos/metabolismo , Tecidos Suporte/química , Vimentina/metabolismo , Animais , Ácido Ascórbico/química , Ácido Ascórbico/farmacologia , Córnea/citologia , Queratinócitos/citologia , Masculino , Nanopartículas/química , Poliuretanos/química , Ratos , Ratos Wistar
7.
Prog Biomater ; 8(3): 169-183, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31414472

RESUMO

The absorption of protein and formation of biofilms on the surface of ophthalmic lenses is one of the factors that destroy their useful performance by causing severe visual impairment, inflammation, dryness and ultimate eye discomfort. Therefore, eye lenses need to be resilient to protein absorption, which is one of the opacity factors in minimizing protein absorption on the lenses. The purpose of this study was to investigate and reduce sediment biotransformation on the surface of the semi-hardened lens based on acrylate by bulk-free radical polymerization method. In this respect, the effect of poly(ethylene glycol) diacrylate (PEGDA) with two different molecular weights of 200 and 600 g/mol on the surface roughness, protein absorption, and hydrophilicity of the lenses were studied. The surface hardness of the lenses, on shore D scale, was measured using a durometer hardness test. The presence of higher molecular weight of PEGDA hydrophilic polymeric monomers reduced the hardness of the lenses. The effect of introducing PEGDA, with two molecular weights, into lens fabrication formulations was studied with respect to their water content parameters and hydrophilicity. The presence of a crosslinker such as poly(ethylene glycol) diacrylates, at two different molecular weights, increased the water content and hydrophilicity of the produced lenses. Surface roughness is associated with the formation of bio-film and accumulation of microorganisms on the surface. Due to the roughness of the lens surface developed in this research, the lenses containing PEGDA 600 exhibited less roughness compared to that of PEGDA 200, which could also affect the absorption of protein. Therefore, according to the results of protein absorption test, the PEGDA 600 lenses showed lower protein absorption, which could be due to their high degree of water absorption and hydrophilicity.

8.
Int J Biol Macromol ; 136: 616-624, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31207331

RESUMO

Cold Atmospheric Plasma (CAP) is used as a promising method in surface modification for immobilization of chondroitin sulfate functional biomacromolecules on PCL nanofibrous substrates for cartilage tissue engineering. The GAG-grafted scaffolds are able to successfully support the attachment and proliferation of mesenchymal stem cells (MSCs). The seeded scaffolds show the chondro-differentiation of MSCs during a 21-days cell culture in a non-differential medium. Expression of SOX9, Collagen10 and Collagen2 proved the chondro-inductive effect of GAG-grafted scaffolds. Besides, no external chondro-genic differential agent was used in the differentiation of MSCs to chondrocyte. The cells passed the last phase of chondrogenesis after 14 days of incubation. Thus, the GAG-fabricated fibrous scaffolds using CAP are potential candidates for cartilage tissue engineering.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/química , Poliésteres/química , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
9.
Int J Biol Macromol ; 132: 63-75, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30928369

RESUMO

Fabrication of gelatin/polyvinyl alcohol/chondroitin sulfate (GEL/PVA/CS) hybrid nanofibrous scaffolds using acetic acid and water as an environmentally friendly solvent system via electrospinning for skin tissue engineering was investigated. Modeling and optimization of the nanofibers were performed using response surface methodology (RSM). The influence of CS ratio on mechanical, physical and biological properties of the nanofibers was studied. PVA was used as a carrier and enhancer of mechanical properties. The mechanical properties of hybrid nanofibers were investigated in dry and wet states. The results showed that in the cross-linked dry state the tensile strength was up to 4 MPa. In the wet state, nanofibers exhibited 200% elongation at break, indicating a toughness behavior which enhances the flexibility for clinical applications. Scanning electron microscope (SEM) confirmed the stability of nanofibrous morphology during degradation up to 21 days. Human dermal fibroblast-green fluorescent protein-positive (HDF-GFP+) cells were cultured on the scaffolds and results showed the appropriate biocompatibility. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was employed to study cell proliferation, and the results confirmed the positive effect of CS ratio on HDF cells attachment as well as proliferation on the nanofibers. Considering the results of in vitro assay, nanofibers containing 15% CS ratio suggested as an optimum CS ratio.


Assuntos
Sulfatos de Condroitina/química , Fenômenos Mecânicos , Nanofibras/química , Pele/citologia , Engenharia Tecidual , Tecidos Suporte/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Humanos , Porosidade , Pele/efeitos dos fármacos , Propriedades de Superfície
10.
Prog Biomater ; 8(2): 65-75, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30919328

RESUMO

Poly(Ɛ-caprolactone) (PCL) is a biocompatible polymer with a high potential to be used in tissue engineering especially in tight tissues. In the current study, cold atmospheric plasma (CAP) is used as a promising method for immobilization of gelatin as a functional biomacromolecule on PCL nanofibrous substrates. The CAP surface modification leads to oxidation of chemical groups existing on the PCL surface without doing any damage to the bulk properties of biomaterials for gelatin biomacromolecule grafting. The water contact angle (WCA) of the CAP-treated surface and gelatin-grafted PCL using CAP indicates an effective increment in the hydrophilicity of the PCL surface. Also to achieve the highest levels of gelatin grafting on the PCL surface, two different grafting methods and gelatin concentration diversity are utilized in the grafting process. The immobilization of gelatin biomacromolecules onto the CAP surface-modified PCL nanofibers is investigated using scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The gelatin-modified PCL substrates revealed uniform nanofibrous morphology with increased average fiber diameter. The results of FTIR spectra, including hydroxyl groups, NH groups, and amide II of gelatin-grafting peaks, confirm the gelatin immobilization on the surface of nanofibers. The metabolic activity of cultured mesenchymal stem cells (MSCs) on the surface-modified scaffolds is evaluated using MTT analysis (P ≤ 0.05). The results of metabolic activity and also SEM and DAPI staining observations indicate proper attachment on the surface and viability for MSCs on the surface-immobilized nanofibrous scaffolds. Therefore, CAP treatment would be an effective method for biomacromolecule immobilization on nanofibers towards the enhancement of cell behavior.

12.
J Biomed Mater Res A ; 107(1): 38-48, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30408321

RESUMO

Tissue engineering is a new technique to help damaged cartilage treatment using cells and scaffolds. In this study we tried to evaluate electrospun scaffolds composed of gelatin/glycosaminoglycan (G/GAG) blend nanofibers in chondrogenesis of bone marrow-derived mesenchymal stem cells (BMMSCs). Scaffolds were fabricated by electrospinning technique with different concentration of glycosaminoglycan (0%, 5%, 10%, and 15%) in gelatin matrix. BMMSCs were cultured on the scaffolds for chondrogenesis process. MTT assay was done for scaffold's biocompatibility and cells viability evaluation. Alcian blue staining was carried out to determine the release of GAG and reverse transcription polymerase chain reaction (RT-PCR) was done for expression of COL2A1 and also immunocytochemistry assay were used to confirm expression of type II collagen. Scaffold with 15% GAG showed better result for biocompatibility (p =0.02). Scanning electron microscopy (SEM) micrographs showed that MSCs have good attachment to the scaffolds. Alcian blue staining result confirmed that cells produce GAG during differentiation time different from GAG in the scaffolds. Also the results for RT-PCR showed the expression of COL2A1 marker. Immunocytochemistry assay for type II collagen confirm that this protein expressed. Scaffold comprising 15% GAG is better results for chondrogenesis and it can be a good applicant for cartilage tissue engineering. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 38-48, 2019.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Gelatina , Glicosaminoglicanos , Células-Tronco Mesenquimais/metabolismo , Nanofibras/química , Células da Medula Óssea/citologia , Gelatina/química , Gelatina/farmacologia , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia
13.
Mater Sci Eng C Mater Biol Appl ; 92: 800-806, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184809

RESUMO

Bead-on-string mats based on poly(lactide-co-glycolide) (PLGA) releasing ß-carotene (ßC) as a natural osteogen were fabricated and used for bone tissue engineering. Mesenchymal stem cells (MSCs) seeded on the scaffolds successfully differentiated to osteoblasts without using any a differential medium. The mats showed a small burst of ß-carotene (24-27%) during the first day and a sustained slow release up to 21 days. The MTT and SEM results indicated good attachment and proliferation of MSCs on the scaffolds. Calcination of scaffolds and expression of RUNX2, SOX9, and osteonectin genes approved the differentiation of seeded MSCs to osteoblasts without using any external osteogenic differential agent. The scaffold loaded with 4% ß-carotene not only induced the early phase of osteogenesis but also advanced the differentiation to the osteoblast maturation phase. Thus, these bead-on-string scaffolds can be used as a substrate for direct bone tissue engineering.


Assuntos
Osso e Ossos/citologia , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Engenharia Tecidual/métodos , beta Caroteno/química , Materiais Biocompatíveis/química , Diferenciação Celular/fisiologia , Humanos , Osteoblastos/citologia , Osteogênese/fisiologia , Tecidos Suporte/química
14.
Prog Biomater ; 7(3): 207-218, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30141130

RESUMO

The nanofibrous structure containing protein and polysaccharide has good potential in tissue engineering. The present work aims to study the role of chitosan in gelatin/chitosan nanofibrous scaffolds fabricated through electrospinning process under optimized condition. The performance of chitosan in gelatin/chitosan nanofibrous scaffolds was evaluated by mechanical tests, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and in vitro cell culture on scaffolds with different gelatin/chitosan blend ratios. To assay the influence of chitosan ratio on biocompatibility of the electrospun gelatin/chitosan scaffolds for skin tissue engineering, the culturing of the human dermal fibroblast cells (HDF) on nanofibers in terms of attachment, morphology and proliferation was evaluated. Morphological observation showed that HDF cells were attached and spread well on highly porous gelatin/chitosan nanofibrous scaffolds displaying spindle-like shapes and stretching. The fibrous morphologies of electrospun gelatin/chitosan scaffolds in culture medium were maintained during 7 days. Cell proliferation on electrospun gelatin/chitosan scaffolds was quantified by MTS assay, which revealed the positive effect of chitosan content (around 30%) as well as the nanofibrous structure on the biocompatibility (cell proliferation and attachment) of substrates.

15.
Carbohydr Polym ; 198: 509-517, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30093028

RESUMO

In the present work, we discuss how oxidation conditions can affect the physical properties of oxidized alginate and crosslinking it with gelatin. We show that the amount of aldehyde groups produced on oxidized alginate backbone increases by increasing alginate concentration even in constant molar ratio of sodium periodate to alginate's repeating units. Increasing the concentration of alginate solution, promote the extent of chain scission and decreases the molecular weight of oxidized alginate, which can be due to the increased possibility of molecular collisions and oxidizing two adjacent uronic acids in the chain. By changing the oxidation condition, therefore, we can produce oxidized alginate with same degree of oxidation but different molecular weights, which change the sol-gel state of alginate-gelatin mixtures. Using oxidized alginates with different molecular weights, we suggest that the aldehyde end groups in alginate chains have the dominant effect in crosslinking with gelatin.

16.
Dent Mater ; 34(9): 1263-1270, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29801684

RESUMO

OBJECTIVES: This is a confirmatory study to evaluate the effect of photoinitiator type and concentration, matrix monomer chemical structure, and nanoparticle incorporation on the physical and mechanical properties of an experimental dentin bonding agent. MATERIALS AND METHODS: Different concentrations of camphorquinone-amine (CQ-A) system, butanedione (BD), and phenylpropanedione (PPD), as photoinitiator, BTDMA, as a comonomer containing carboxylic acid groups, and silica nanoparticles as reinforcing inorganic filler were incorporated into a methacrylate base experimental dental adhesive. The effect of these ingredients, as independent variables, on the shrinkage kinetics, flexural strength and modulus, and microshear bond strength of the adhesives were then investigated. The results were analyzed using one-way ANOVA and Tukey's post-hoc test at the significance level of 0.05. RESULTS: The results indicate that the efficiency of CQ-A initiator system is diminished in the presence of the acidic monomer BTDMA while the photopolymerization is efficiently progressed with BD as initiator. PPD shows the lowest efficiency in the photopolymerization of the adhesives. BTDMA as a monomer with the capability of interaction with tooth structure provides adhesive with improved microshear bond strength to dentin. Incorporation of silica nanoparticles at low concentrations enhances the flexural and microshear strength of the dentin bonding agent. SIGNIFICANCE: Understanding the structure-property relationship in dental adhesives may help the material selection in clinical dentistry. The study elucidates the relationship between monomer structure, initiator type, and nanofiller and physical and mechanical properties in dental adhesives.


Assuntos
Adesivos Dentinários/química , Nanopartículas/química , Fotoiniciadores Dentários/química , Relação Estrutura-Atividade , Condicionamento Ácido do Dente , Aminas/química , Butanonas/química , Cânfora/análogos & derivados , Cânfora/química , Módulo de Elasticidade , Resistência à Flexão , Humanos , Técnicas In Vitro , Teste de Materiais , Polimerização , Resistência ao Cisalhamento , Dióxido de Silício/química
17.
Int J Biol Macromol ; 114: 1248-1256, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29627465

RESUMO

Electrospun nanofibers have attracted a lot of attention in recent years in tissue engineering applications. In this research, novel polyvinyl alcohol/gelatin/chondroitin sulfate (PVA/GE/Cs) nanofibrous scaffolds using non-carcinogen solvent system via electrospinning technique was evaluated. A solvent system containing water and acetic acid was used as a safe solvent system to obtain a homogenous mixture with suitable solvent properties and finally non-toxic nanofibrous scaffolds. The effect of water to the acetic acid ratio in the solvent system (7:3, 6:4, 5:5, 4:6, 3:7) and also polymer concentration (8, 9, 10w/v %) on nanofibers morphology was investigated. The appropriate flow rate and voltage ranges to obtain uniform and bead-free electrospun scaffold were investigated. Effect of different Cs ratio (0, 10, 15 and 20wt%) on solution properties was evaluated. Influence of Cs ratio on chemical, physical and thermal properties of the electrospun scaffolds was studied. The results of cell toxicity indicated that prepared PVA/GE/Cs scaffolds have no cell toxicity. SEM results demonstrated that L929 mouse fibroblast cells have suitable interaction with scaffold surface and also attached and proliferated well on the prepared substrate after 24 and 48h and also have a potential for using in tissue engineering.


Assuntos
Sulfatos de Condroitina/química , Fibroblastos/metabolismo , Gelatina/química , Nanofibras/química , Álcool de Polivinil/química , Tecidos Suporte/química , Animais , Linhagem Celular , Fibroblastos/citologia , Teste de Materiais , Camundongos
18.
Int J Biol Macromol ; 115: 243-248, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29654862

RESUMO

This research focused on the physical properties and cell compatibility of nanofibrous scaffolds based on polycaprolactone/chitosan (PCL/CTS) and PCL/carboxymethyl chitosan (PCL/CMC) blends for bone tissue engineering application. Scaffolds were fabricated by electrospinning technique. SEM images showed that the undesirable ultrafine and splitting fibers in PCL/CTS scaffolds are eliminated by replacing CTS with CMC. PCL/CMC scaffolds exposed significantly improved surface hydrophilicity improvement comparing to PCL/CTS ones. The water contact angle of PCL scaffold was reduced on the addition of 15% CMC from 123 ±â€¯1° to 51 ±â€¯3° in high concentration of CMC scaffold. The average diameter of fibers in PCL/CTS 15% and PCL/CMC 15% were 439 and 356 nm, respectively, which demonstrated higher concentrations of CMC resulted in decrease fibers diameter than other blended scaffolds. FTIR spectroscopy confirmed the composition of PCL/CTS and PCL/CMC scaffolds. The culturing of human osteoblast cells (MG63) on the scaffolds showed that all scaffolds are biocompatible. The PCL/CMC nanofibers exhibited promoting proliferation trend, compared to the PCL and PCL/CTS ones, especially at maximum concentrations of CMC. The results demonstrate that the PCL/CMC electrospun scaffolds can be an excellent candidate for bone tissue engineering application.


Assuntos
Materiais Biocompatíveis/farmacologia , Osso e Ossos/citologia , Quitosana/análogos & derivados , Nanofibras/química , Poliésteres/química , Engenharia Tecidual , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Osso e Ossos/efeitos dos fármacos , Linhagem Celular , Quitosana/química , Teste de Materiais
19.
Prog Biomater ; 7(1): 73, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29363003

RESUMO

The original version of this article unfortunately contained a mistake: The spelling of the Ebrahim Gafar-Zadehs' name was incorrect. The corrected name is given above.

20.
Prog Biomater ; 6(3): 67-74, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28508183

RESUMO

A multi-component acrylate-based copolymer system especially designed for application as ocular lenses is developed through free-radical, bulk polymerization of a system containing hydroxyethyl methacrylate, methyl methacrylate, triethylene glycol dimethacrylate, dimethyl itaconate, 3-(trimethoxysilyl) propylmethacrylate, Polyhedraloligomeric silsesquioxane-acrylate (POSS-acrylate) and AIBN as an initiator. The progress of the reaction was monitored by Fourier transform infrared spectroscopy (FTIR). The effect of increasing concentration of the components on the hardness of the synthesized lenses was measured by Shore Durometer before and after immersion in PBS solutions. Extraction test method was performed to analyze the biocompatibility of the fabricated lenses. In this research the Taguchi method was employed to achieve the optimal hardness property which plays a critical role in final application of the lens materials. The Taguchi trial for ocular lens hardness was configured in an L16 orthogonal array, by five control factors, each with four level settings. The results showed that 3-(trimethoxysilyl) propyl methacrylate decreases and 2-hydroxyethylmethacrylate increases, polyhedraloligomeric silsesquioxane with a cage-like structure, methyl methacrylate and dimethyl itaconate increase the hardness. Proliferation and growth of the cells showed that there is no toxic substance extracted from the lenses which can interfere with the cell growth.

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