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1.
Gene ; 720: 144096, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31476405

RESUMO

Biologically active materials and polymeric materials used in tissue engineering have been one of the most attractive research areas in the past decades, especially the use of easily accessible materials from the patients that reduces or eliminates any patient's immune response. In this study, electrospun nanofibrous scaffolds were fabricated by using polyvinyl-alcohol (PVA), chitosan and hydroxyapatite (HA) polymers and platelet-rich plasma (PRP) as a bioactive substance isolated from human blood. Fabricated scaffold's structure and cytotoxicity were evaluated using scanning electron microscope and MTT assays. Scaffolds osteoinductivity was investigated by osteogenic differentiation of the mesenchymal stem cells (MSCs) at the in vitro level and then its osteoconductivity was examined by implanting at the critical-sized rat calvarial defect. The in vitro results showed that scaffolds have a good structure and good biocompatibility. Alkaline phosphatase activity, calcium content and gene expression assays were also demonstrated that their highest amount was detected in MSCs-seeded PVA-chitosan-HA(PRP) scaffold. For this reason, this scaffold alone and along with the MSCs was implanted to the animal defects. The in vivo results demonstrated that in the animals implanted with PVA-chitosan-HA(PRP), the defect was repaired to a good extent, but in those animals that received MSCs-seeded PVA-chitosan-HA(PRP), the defects was almost filled. It can be concluded that, PVA-chitosan-HA(PRP) alone or when stem cells cultured on them, has a great potential to use as an effective bone implant.


Assuntos
Diferenciação Celular , Nanofibras/química , Osteogênese , Plasma Rico em Plaquetas/química , Procedimentos Cirúrgicos Reconstrutivos , Crânio/cirurgia , Animais , Células Cultivadas , Quitosana/química , Durapatita/química , Masculino , Células-Tronco Mesenquimais/citologia , Álcool de Polivinil/química , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Tecidos Suporte
2.
J Agric Food Chem ; 67(35): 9907-9915, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31436102

RESUMO

The impact of covalent or non-covalent bound gallic acid (GA) on the formation, physicochemical properties, and digestion of ovotransferrin (OTF) nanofibrils was comprehensively studied. Thioflavin T fluorescence results revealed that bound GA could inhibit OTF nanofibrillation and that the fibril-inhibitory activity of bound GA was dose dependent. Covalent bound GA exerted stronger inhibition on OTF nanofibrillation than an equal amount of non-covalent bound GA. Atomic force microscopy revealed that covalent bound GA shortened OTF nanofibrils significantly, while non-covalent bound GA did not change the contour length of OTF fibrils remarkably. Bound GA altered diameter of OTF nanofibrils. Both covalent and non-covalent bound GA could alter the zeta potential, surface hydrophobicity, and rheological properties of OTF nanofibrils. Bound GA endowed OTF nanofibrils with a strong antioxidant activity. In vitro gastrointestinal digestion results showed that covalent bound GA elevated the fibril digestion rate better than non-covalent bound GA. Polyphenol binding provided a new approach to modulating the physicochemical properties of protein nanofibrils.


Assuntos
Conalbumina/química , Ácido Gálico/química , Nanofibras/química , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Galinhas , Conalbumina/metabolismo , Digestão , Ácido Gálico/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Modelos Biológicos , Reologia
3.
Int J Nanomedicine ; 14: 5033-5050, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371945

RESUMO

Background: Repairs to deep skin wounds continue to be a difficult issue in clinical practice. A promising approach is to fabricate full-thickness skin substitutes with functions closely similar to those of the natural tissue. For many years, a three-dimensional (3D) collagen hydrogel has been considered to provide a physiological 3D environment for co-cultivation of skin fibroblasts and keratinocytes. This collagen hydrogel is frequently used for fabricating tissue-engineered skin analogues with fibroblasts embedded inside the hydrogel and keratinocytes cultivated on its surface. Despite its unique biological properties, the collagen hydrogel has insufficient stiffness, with a tendency to collapse under the traction forces generated by the embedded cells. Methods: The aim of our study was to develop a two-layer skin construct consisting of a collagen hydrogel reinforced by a nanofibrous poly-L-lactide (PLLA) membrane pre-seeded with fibroblasts. The attractiveness of the membrane for dermal fibroblasts was enhanced by coating it with a thin nanofibrous fibrin mesh. Results: The fibrin mesh promoted the adhesion, proliferation and migration of the fibroblasts upwards into the collagen hydrogel. Moreover, the fibroblasts spontaneously migrating into the collagen hydrogel showed a lower tendency to contract and shrink the hydrogel by their traction forces. The surface of the collagen was seeded with human dermal keratinocytes. The keratinocytes were able to form a basal layer of highly mitotically-active cells, and a suprabasal layer. Conclusion: The two-layer skin construct based on collagen hydrogel with spontaneously immigrated fibroblasts and reinforced by a fibrin-coated nanofibrous membrane seems to be promising for the construction of full-thickness skin substitute.


Assuntos
Colágeno/farmacologia , Fibrina/farmacologia , Hidrogéis/farmacologia , Membranas Artificiais , Nanofibras/química , Poliésteres/farmacologia , Pele Artificial , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Derme/citologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Recém-Nascido , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Ratos
4.
Chem Commun (Camb) ; 55(68): 10158-10161, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31389420

RESUMO

We developed a chemical method to covalently functionalize cellulose nanofibers and cellulose paper with mannoside ligands displaying a strong affinity for the FimH adhesin from pathogenic E. coli strains. Mannose-grafted cellulose proved efficient to selectively bind FimH lectin and discriminate pathogenic E. coli strains from non-pathogenic ones. These modified papers are valuable tools for diagnosing infections promoted by E. coli, such as cystitis or inflammatory bowel diseases, and the concept may be applicable to other life-threatening pathogens.


Assuntos
Celulose/química , Escherichia coli K12/isolamento & purificação , Mananas/química , Nanofibras/química , Adesinas de Escherichia coli/metabolismo , Aderência Bacteriana/efeitos dos fármacos , Técnicas de Tipagem Bacteriana/instrumentação , Técnicas de Tipagem Bacteriana/métodos , Linhagem Celular Tumoral , Celulose/metabolismo , Escherichia coli K12/química , Fezes/microbiologia , Proteínas de Fímbrias/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Mananas/metabolismo , Papel , Ligação Proteica
5.
Int J Nanomedicine ; 14: 4261-4276, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31289441

RESUMO

Purpose: In the field of small-caliber vascular scaffold research, excellent vascular remodeling is the key to ensuring anticoagulant function. We prepared an off-the-shelf bi-layered vascular scaffold with a dense inner layer and a loose outer layer and evaluated its remodeling capabilities by in vivo transplantation. Materials and Methods: Based on poly(L-lactide-co-ε-caprolactone) (PLCL), silk fibroin(SF), and heparin (Hep), PLCL/SF/Hep bi-layered scaffolds and PLCL/Hep bi-layered scaffolds were prepared by electrospinning. The inner layer was a PLCL/SF/Hep or PLCL/Hep nanofiber membrane, and the outer layer was PLCL/SF nano yarn. The in vitro tests included a hydrophilicity test, mechanical properties test, and blood and cell compatibility evaluation. The in vivo evaluation was conducted via single rabbit carotid artery replacement and subsequent examinations, including ultrasound imaging, immunoglobulin assays, and tissue section staining. Results: Compared to the PLCL/Hep nanofiber membrane, the hydrophilicity of the PLCL/SF/Hep nanofiber membrane was significantly improved. The mechanical strength met application requirements. Both the blood and cell compatibility were optimal. Most importantly, the PLCL/SF/Hep scaffolds maintained lumen patency for 3 months after carotid artery transplantation in live rabbits. At the same time, CD31 and α-SMA immunofluorescence staining confirmed bionic endothelial and smooth muscle layers remodeling. Conclusion: Using this hybrid strategy, PLCL and SF were combined to manufacture bi-layered small-caliber vascular scaffolds; these PLCL/SF/Hep scaffolds showed satisfactory vascular remodeling.


Assuntos
Fibroínas/química , Heparina/farmacocinética , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Artérias Carótidas , Proliferação de Células , Liberação Controlada de Fármacos , Heparina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Nanofibras/química , Adesividade Plaquetária , Próteses e Implantes , Coelhos
6.
Int J Nanomedicine ; 14: 2693-2703, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354260

RESUMO

Background: Silver, incorporation with natural or synthetic polymers, has been used as an effective antibacterial agent since decades. Silver has potential applications in healthcare especially in nanoparticles form but silver sulfadiazine (AgSD) is the most efficient antibacterial agent especially for burn wound dressings. Method: In this report, mechanical, structural, and antibacterial properties of PAN nanofibers incorporation with silver sulfadiazine are mainly focused. AgSD was loaded for the first time on electrospinning as well as self-synthesized AgSD on PAN nanofibers by solution immersion method and then compared the results of both. Results: Occurrence of chemical reaction among the functional groups of AgSD and PAN were analyzed using FTIR, for both types of specimen. Morphological and surface properties of prepared nanofiber mats were characterized by scanning electron microscope, and it resulted in uniform nanofibers without bead formation. Diameter of nanofibers was slightly increased with addition of AgSD by in situ and immersion methods respectively. Nanoparticles distribution was analyzed by transmission electron microscopy. Thermal properties were analyzed by thermo-gravimetric analyzer and it was observed that AgSD decreased thermal stability of PAN which is better from biomedical perspective. X-ray diffraction declared crystalline structure of nanofiber mats. Presence of Ag and S contents in nanofiber mats was analyzed by X-ray photo spectroscopy. Antibacterial properties of nanofiber mats were investigated by disc diffusion method was carried out. E. coli and Bacillus bacteria strain were used as gram-negative and gram-positive respectively. Zone inhibition of the bacteria was used as a tool to determine effectiveness of AgSD released from PAN nanofiber mats. The antibacterial properties of PAN nanofibers impregnated with AgSD were determined with both types of bacteria strains to compare with control one. Conclusion: On the basis of characterization results it is concluded that PAN/AgSD (immersion) nanofiber mats have better structural and antibacterial properties than that of PAN/AgSD (in situ) nanofiber mats. So, from our point of view, self-synthesized AgSD is recommended for further production of nanofiber mats for antibacterial applications.


Assuntos
Resinas Acrílicas/química , Antibacterianos/farmacologia , Nanofibras/química , Sulfadiazina de Prata/farmacologia , Bacillus/efeitos dos fármacos , Módulo de Elasticidade , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Espectroscopia Fotoeletrônica , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Resistência à Tração , Termogravimetria , Difração de Raios X
7.
Food Chem ; 298: 125041, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261000

RESUMO

Edible packaging films play an important role in extending the shelf life of food products. In this work, the properties of cellulose nanofiber (CNF) reinforced hemicelluloses/chitosan-based edible films with xylooligosaccharides (XOS) have been evaluated. Results showed that the tensile strength (TS) of the film can be increased by 2.5 times with adding 5 wt% CNF. Incorporating 1.79-7.18% XOS into hemicelluloses-chitosan matrix only caused slightly higher water vapor permeability, and the composite films exhibited good hydrophobicity, thermal stability, and high transparency. The hemicelluloses/chitosan films with 1.79-5.38% XOS had higher TS (42.7-50.7 MPa) and lower oxygen permeability (OP, 4.95-5.06 cm3 µm/m2·day·kPa) than those containing 7.18% XOS. Additionally, ∼92.6% XOS in films can be released in simulated gastric fluid within 60 min. Overall, XOS (1.79-5.38%) with prebiotic properties can be added to films successfully to improve the functionality and the films were fit for food-packaging where high TS and low OP are required.


Assuntos
Celulose/química , Quitosana/química , Glucuronatos/química , Nanofibras/química , Oligossacarídeos/química , Embalagem de Alimentos/métodos , Suco Gástrico , Humanos , Microscopia Eletrônica de Varredura , Permeabilidade , Polissacarídeos/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Difração de Raios X
8.
Chem Commun (Camb) ; 55(59): 8564-8566, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31271158

RESUMO

Diphenylalanine (FF), as the smallest unit and core recognition motif of ß-amyloid (Aß), could self-assemble into nanofibers, which induces an early onset of Alzheimer's disease (AD). Green/near-infrared fluorescent BODIPY probes were designed and synthesized to detect FF-assembly, providing unique insights into the chemical and molecular mechanism of Aß aggregation and drug development for AD.


Assuntos
Compostos de Boro/química , Corantes Fluorescentes/química , Fenilalanina/análogos & derivados , Técnicas Biossensoriais/métodos , Compostos de Boro/síntese química , Corantes Fluorescentes/síntese química , Nanofibras/química , Fenilalanina/análise , Fenilalanina/química , Multimerização Proteica
9.
J Photochem Photobiol B ; 197: 111539, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31301638

RESUMO

Treatment of burn injury is clinically challenging one, therefore several steps and noteworthy approaches have been taken to improve wound mechanisms. Citrus pectin plays a stabilizing agent to synthesis of ZnO nanoparticles (ZnO NPs). The present study is focused on ZnO loaded collagen/chitosan nanofibrous were synthesized by electrospinning method using ZnO NPs. The chemical structure, phase purity and morphological observation were investigated under spectroscopic and mircoscopic techniques and demonstrated their suitable properties as a wound healing material. In addition, that prepared nanoparticles loaded biopolymeric fibrous nanomaterial showed suitable antibacterial activity against S. aureus and E. coli bacterial pathogens and also in vitro studies was confirmed the enhanced proliferation, cell viability and biocompatibility. In vitro evaluations have been exhibited acceptable cell proliferation is observed throughout the ZnO loaded Coll/CS nanofibrous within 3 days, which was comparable to the control material. In vivo wound healing ability was monitored on the rat wound experimental model. From the in vivo observations, revealed that the loaded of ZnO NPs with Coll/CS nanofibrous can effectively quicken wound healing mechanism, expressed in the initial stage healing process. These results suggest that ZnO loaded collagen/chitosan nanofibrous is a potential candidate for wound healing applications with enhanced biological properties.


Assuntos
Queimaduras/patologia , Quitosana/química , Colágeno/química , Nanopartículas Metálicas/química , Nanofibras/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bacteriemia/prevenção & controle , Queimaduras/veterinária , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Nanofibras/uso terapêutico , Nanofibras/toxicidade , Ratos , Pele/efeitos dos fármacos , Pele/patologia , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química
10.
Anal Bioanal Chem ; 411(16): 3631-3640, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31175397

RESUMO

In this research, electrospun polycaprolactam nanofibers were collected on a fine stainless steel mesh sheet without a binder, and a layer of conductive polyaniline was chemically deposited on the nanofibers. The polyaniline immobilized on the polycaprolactam nanofibers provided high electrical conductivity, acceptable mechanical stability, and a large surface area. This assembly was then used as a working electrode in electrochemically controlled solid-phase microextraction (EC-SPME), a fast and environmentally friendly method. The polymer layers were characterized by SEM and FTIR techniques. Significant factors affecting the EC-SPME efficiency were investigated, including the desorption conditions, the sorbent used, the pH of the sample solution, the extraction voltage, the extraction time, and the ionic strength. Under the optimum conditions, the limits of detection and quantification for the target analytes were 0.9-1.8 µg L-1 and 3.0-6.1 µg L-1, respectively. The linear dynamic range was 5-2000 µg L-1, with R2 > 0.993. The method was coupled with HPLC analysis and applied to the determination of angiotensin ΙΙ receptor antagonists (ARA-ΙΙs) in human plasma, and relative recoveries of 91.1-104.3% with RSDs of ≤8.3% were obtained.


Assuntos
Antagonistas de Receptores de Angiotensina/sangue , Compostos de Anilina/química , Caprolactama/química , Cromatografia Líquida de Alta Pressão/métodos , Técnicas Eletroquímicas/métodos , Nanofibras/química , Microextração em Fase Sólida/métodos , Adsorção , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Concentração Osmolar , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Int J Nanomedicine ; 14: 3929-3941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213809

RESUMO

Introduction: Hierarchical nanofibrous scaffolds are emerging as a promising bone repair material due to their high cell adhesion activity and nutrient permeability. However, the existing method for hierarchical nanofibrous scaffolds fabrication is complicated and not perfectly suitable for further biomedical application in view of both structure and function. In this study, we constructed a hierarchical nanofibrous poly (l-lactic acid)/poly(ε-caprolactone) (PLLA/PCL) scaffold and further evaluated its bone healing ability. Methods: The hierarchical PLLA/PCL nanofibrous scaffold (PLLA/PCL) was prepared by one-pot TIPS and then rapidly mineralized at room temperature by an electrochemical deposition technique. After electrode-positioning at 2 V for 2 hrs, a scaffold coated with hydroxyapatite (M-PLLA/PCL) could be obtained. Results: The pore size of the M-PLLA/PCL scaffold was hierarchically distributed so as to match the biophysical structure for osteoblast growth. The M-PLLA/PCL scaffold showed better cell proliferation and osteogenesis activity compared to the PLLA/PCL scaffold. Further in vivo bone repair studies indicated that the M-PLLA/PCL scaffold could accelerate defect healing in 12 weeks. Conclusion: The results of this study implied that the as-prepared hydroxyapatite coated hierarchical PLLA/PCL nanofibrous scaffolds could be developed as a promising material for efficient bone tissue repair after carefully tuning the TIPS and electrodeposition parameters.


Assuntos
Regeneração Óssea/fisiologia , Galvanoplastia/métodos , Minerais/química , Nanofibras/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Eletricidade , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , Engenharia Tecidual/métodos , Microtomografia por Raio-X
12.
Int J Nanomedicine ; 14: 4007-4016, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213812

RESUMO

Background: This study exploited sheath-core-structured lidocaine/human EGF (hEGF)-loaded anti-adhesive poly[(d,l)-lactide-co-glycolide] (PLGA) nanofibrous films for surgical wounds via a co-axial electrospinning technique. Materials and methods: After spinning, the properties of the co-axially spun membranes were characterized by scanning electron microscopy, laser-scanning confocal microscopy, Fourier Transform Infrared spectrometry, water contact angle measurements, and tensile tests. Furthermore, a HPLC analysis and an ELISA evaluated the in vitro and in vivo release curves of lidocaine and hEGF from the films. Results: PLGA anti-adhesion nanofibers eluted high levels of lidocaine and hEGF for over 32 and 27 days, respectively, in vitro. The in vivo evaluation of post-surgery recovery in a rat model demonstrated that no adhesion was noticed in tissues at 2 weeks after surgery illustrating the anti-adhesive performance of the sheath-core-structured nanofibers. Nanofibrous films effectively released lidocaine and hEGF for >2 weeks in vivo. In addition, rats implanted with the lidocaine/hEGF nanofibrous membranes exhibited greater activities than the control demonstrating the pain relief efficacy of the films. Conclusion: The empirical outcomes suggested that the anti-adhesive nanofibrous films with extended release of lidocaine and hEGF offer post-operative pain relief and wound healing.


Assuntos
Adesivos/uso terapêutico , Fator de Crescimento Epidérmico/uso terapêutico , Nanofibras/química , Dor/tratamento farmacológico , Ferida Cirúrgica/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Adesivos/farmacologia , Anestésicos Locais/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Fator de Crescimento Epidérmico/farmacologia , Humanos , Lidocaína/farmacologia , Lidocaína/uso terapêutico , Masculino , Nanofibras/ultraestrutura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Ferida Cirúrgica/patologia
13.
Carbohydr Polym ; 219: 113-120, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151507

RESUMO

Honey is an ancient natural wound-healing agent and has been reintroduced to modern clinical wound care as it has various bioactivities. In this study, honey was incorporated into an alginate/PVA-based electrospun nanofibrous membrane to develop an efficient wound dressing material. The morphology and chemical composition of the nanofibrous membrane were observed by scanning electron microscopy and characterized via Fourier transform infrared spectroscopy, respectively, demonstrating that honey was successfully introduced to the nanofibers. The nanofibrous membranes with increasing honey content showed enhanced antioxidant activity, suggesting the ability to control the overproduction of reactive oxygen species. Disc diffusion assay and dynamic contact assay proved the antibacterial activity of the honey loaded nanofibers towards Gram-positive bacterium (Staphylococcus aureus) and Gram-negative bacterium (Escherichia coli). The cytotoxicity assay illustrated the non-cytotoxicity and biocompatibility of the nanofibrous membranes. Therefore, the developed honey/alginate/PVA nanofibrous membranes are promising for wound dressings.


Assuntos
Alginatos , Antibacterianos , Antioxidantes , Mel , Membranas/química , Nanofibras , Alginatos/química , Alginatos/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Apiterapia , Escherichia coli/efeitos dos fármacos , Humanos , Camundongos , Células NIH 3T3 , Nanofibras/química , Nanofibras/uso terapêutico , Nanofibras/toxicidade , Curativos Oclusivos , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Cicatrização
14.
Chemosphere ; 233: 405-413, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31176904

RESUMO

Water-stable PVA/PAA nanofibers were fabricated through electrospinning and evaluated for their performance in lead (Pb(II)) and cadmium (Cd(II)) removal from water in a batch experiment. The adsorption mechanism of Pb(II) was explored using the extended X-ray absorption fine structure (EXAFS) spectroscopic analysis. The PVA/PAA nanofibers showed a pH-dependent behavior for heavy metal removal, and its adsorption capacities for Pb(II) and Cd(II) could reach as high as 159 and 102 mg/g, respectively. The calcium ion (Ca(II)) had no effect on Pb(II) removal at pH 5.0 whereas it significantly reduced Cd(II) removal at pH 7.0. The adsorption of Pb(II) and Cd(II) was spontaneous and exothermic in nature with a decrease in randomness. The saturated PVA/PAA nanofibers could be regenerated using acidic solutions for reuse. The Fourier-transform infrared (FTIR) spectroscopic analysis indicated the formation of surface complexes between adsorbed Pb(II) and Cd(II) and carboxyl groups on PVA/PAA nanofibers. Moreover, EXAFS analysis suggested that a Pb(II) cation was chelated with three carboxyl groups on the nanofibers. This molecular-level adsorption structure was successfully implemented into a surface complexation model for the prediction of the macroscopic Pb(II) and Cd(II) adsorption behaviors. The results gained from this study provided complementary information on heavy metal removal by a new generation of adsorbents and improved the fundamental understanding for the removal process.


Assuntos
Resinas Acrílicas/química , Metais Pesados/análise , Modelos Teóricos , Nanofibras/química , Álcool de Polivinil/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Cádmio/análise , Concentração de Íons de Hidrogênio , Cinética , Chumbo/análise , Águas Residuárias/química
15.
Int J Nanomedicine ; 14: 3893-3909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239663

RESUMO

Background: Photothermal and chemotherapy treatment has been frequently studied for cancer therapy; however, chemotherapy is equally toxic to both normal and cancer cells. The clinical application value of most kinds of photothermal transforming agents remains limited, due to their poor degradation and minimal accumulation in tumors. Materials and methods: We reported the synthesis of photothermal transforming agents (MoS2) and chemotherapeutic (doxorubicin, DOX) co-loaded electrospun nanofibers using blend electrospinning for the treatment of postoperative tumor recurrence. Results: Under the irradiation of an 808 nm laser, the as-prepared chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an admirable photothermal conversion capability with a photothermal conversion efficiency of 23.2%. These composite nanofibers are in vitro and in vivo biocompatible. In addition, they could control the sustained release of DOX and the generated heat can sensitize the chemotherapeutic efficacy of DOX via enhancing its release rate. Their chemo-/photothermal combined therapy efficiency was systematically studied in vitro and in vivo. Instead of circulating with the body fluid, MoS2 was trapped by the nanofibrous matrix in the tumor and so its tumor-killing ability was not compromised, thus rendering this composite nanofiber a promising alternative for future clinical translation within biomedical application fields. Conclusion: Chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an excellent photothermal conversion capability with a photothermal conversion efficiency of 23.2% and can completely inhibit the postoperative tumor reoccurrence.


Assuntos
Dissulfetos/química , Doxorrubicina/uso terapêutico , Molibdênio/química , Nanofibras/química , Nanotecnologia/métodos , Neoplasias/terapia , Fototerapia , Animais , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HT29 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanofibras/ultraestrutura , Recidiva Local de Neoplasia/patologia , Neoplasias/sangue , Neoplasias/patologia , Neoplasias/cirurgia , Padrões de Referência , Resultado do Tratamento
16.
Photochem Photobiol Sci ; 18(8): 1923-1932, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31147667

RESUMO

Drug-resistant pathogens, particularly those that result in hospital acquired infections (HAIs), have emerged as a critical priority for the World Health Organization. To address the need for self-disinfecting materials to counter the threat posed by the transmission of these pathogens from surfaces to new hosts, here we investigated if a cationic BODIPY photosensitizer, embedded via electrospinning into nylon and polyacrylonitrile (PAN) nanofibers, was capable of inactivating both bacteria and viruses via antimicrobial photodynamic inactivation (aPDI). Materials characterization, including fiber morphology and the degree of photosensitizer loading, was assessed by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and demonstrated that the materials were comprised of nanofibers (125-215 nm avg. diameter) that were thermostable to >300 °C. The antimicrobial potencies of the resultant Nylon-BODIPY(+) and PAN-BODIPY(+) nanofiber materials were evaluated against four strains of bacteria recognized by the World Health Organization as either critical or high priority pathogens: Gram-positive strains methicillin-resistant S. aureus (MRSA; ATCC BAA-44) and vancomycin-resistant E. faecium (VRE; ATCC BAA-2320), and Gram-negative strains multidrug-resistant A. baumannii (MDRAB; ATCC BAA-1605) and NDM-1 positive K. pneumoniae (KP; ATCC BAA-2146). Our results demonstrated the detection limit (99.9999%; 6 log units reduction in CFU mL-1) photodynamic inactivation of three strains upon illumination (30-60 min; 40-65 ± 5 mW cm-2; 400-700 nm): MRSA, VRE, and MDRAB, but only minimal inactivation (47-75%) of KP. Antiviral studies employing PAN-BODIPY(+) against vesicular stomatitis virus (VSV), a model enveloped virus, revealed complete inactivation. Taken together, the results demonstrate the potential for electrospun BODIPY(+)-embedded nanofiber materials as the basis for pathogen-specific anti-infective materials, even at low photosensitizer loadings.


Assuntos
Resinas Acrílicas/farmacologia , Antibacterianos/farmacologia , Compostos de Boro/farmacologia , Nylons/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Resinas Acrílicas/química , Antibacterianos/química , Compostos de Boro/química , Klebsiella pneumoniae/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanofibras/química , Nylons/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Enterococos Resistentes à Vancomicina/efeitos dos fármacos
17.
Nat Commun ; 10(1): 2156, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089136

RESUMO

The extended life expectancy and the raise of accidental trauma call for an increase of osteoarticular surgical procedures. Arthroplasty, the main clinical option to treat osteoarticular lesions, has limitations and drawbacks. In this manuscript, we test the preclinical safety of the innovative implant ARTiCAR for the treatment of osteoarticular lesions. Thanks to the combination of two advanced therapy medicinal products, a polymeric nanofibrous bone wound dressing and bone marrow-derived mesenchymal stem cells, the ARTiCAR promotes both subchondral bone and cartilage regeneration. In this work, the ARTiCAR shows 1) the feasibility in treating osteochondral defects in a large animal model, 2) the possibility to monitor non-invasively the healing process and 3) the overall safety in two animal models under GLP preclinical standards. Our data indicate the preclinical safety of ARTiCAR according to the international regulatory guidelines; the ARTiCAR could therefore undergo phase I clinical trial.


Assuntos
Cartilagem Articular/fisiopatologia , Transplante de Células-Tronco Mesenquimais/métodos , Nanofibras/química , Osteoartrite/terapia , Tecidos Suporte/química , Animais , Regeneração Óssea , Linhagem Celular , Terapia Combinada/métodos , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais , Osteoartrite/fisiopatologia , Ratos , Ratos Nus , Ovinos , Engenharia Tecidual/métodos , Cicatrização/fisiologia
18.
Talanta ; 201: 474-479, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122453

RESUMO

In the present study, a new graphene based nanofibers material (Polyacrylonitrile/Graphene Oxide (PAN/GO)) was used for microextraction by packed sorbent (MEPS). The PAN/GO nanofiber was synthesized using the electrospinning technique. MEPS online with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilized for the extraction and determination of two local anesthetic drugs (lidocaine, prilocaine) and their major metabolites (2,6-xylidine, o-toluidine) in human plasma samples. Parameters affecting the extraction efficiency were investigated and optimized (including sample pH, washing solution and elution solution). The validation of the method was based on FDA (Food and Drug Administration) guidelines for bioanalytical methods. The calibration curve ranged from 2.00 to 2000 nmol/L for lidocaine and prilocaine, and from 10.0 to 2000 nmol/L for 2,6-xylidine and o-toluidine. The coefficient of determination (R2) values were 0.996, 0.995, 0.995, 0.996 (n = 3) for lidocaine, prilocaine, 2,6-xylidine and o-toluidine, respectively. The extraction recovery was 93.0% for lidocaine, 96.0% for prilocaine, 68.0% for 2,6-xylidine and 69.0% for o-toluidine. The limits of detection (LODs) were 0.25, 0.50, 2.50, 1.25 nmol/L for lidocaine, prilocaine, 2,6-xylidine and o-toluidine, respectively. The lower limits of quantification (LLOQs) were 2.0 nmol/L for lidocaine and prilocaine, and 10 nmol/L for 2,6-xylidine and o-toluidine, respectively. The accuracy values for the quality control (QC) samples were in the range of 91.0-111% for lidocaine, 92.0-118% for prilocaine, 84.0-98.0% for 2,6-xylidine and 82.0-90.0% for o-toluidine. The inter-day precisions for QC samples ranged from 7.0% to 11.8% for lidocaine, from 8.6% to 11.7% for prilocaine, from 8.0% to 10.0% for 2,6-xylidine and from 8.0% to 9.0% for o-toluidine. The matrix effect values were in the range of -2.3% to -8.6% for lidocaine, -2.7% to -10.2% for prilocaine, 4.8%-5.2% for 2, 6-xylidine and -8.2% to 9.4% for o-toluidine.


Assuntos
Resinas Acrílicas/química , Anestésicos Locais/sangue , Compostos de Anilina/sangue , Grafite/química , Nanofibras/química , Microextração em Fase Sólida/métodos , Resinas Acrílicas/síntese química , Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Grafite/síntese química , Humanos , Concentração de Íons de Hidrogênio , Lidocaína/sangue , Limite de Detecção , Prilocaína/sangue , Espectrometria de Massas em Tandem/métodos , Toluidinas/sangue
19.
J Chromatogr A ; 1600: 87-94, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31060784

RESUMO

In this paper, poly m-aminophenol/nylon 6/graphene oxide (PmAP/N6/GO) electrospun nanofiber was fabricated and applied as an efficient sorbent for thin film microextraction (TFME) of phthalate esters (PAEs). The porosity, morphology, wettability, solvent stability and chemical structure of the prepared nanofiber were evaluated. The prepared PmAP/N6/GO nanofiber film exhibited some prominent advantages such as large surface area, porous fibrous structure, high stability, good hydrophilicity and excellent extraction efficiency. Afterward, thin film microextraction-gas chromatography-mass spectroscopy (TFME-GC-MS) method was developed for the quantitative analysis of PAEs, and the effective parameters on the extraction performance were investigated systematically. At the optimal operating conditions, the large linearity range (0.5-250 ng mL-1) with excellent correlation coefficient (<0.998) had been acquired for this method. Moreover, low limits of detection (LODs) (0.1-0.15 ng mL-1) exhibited the satisfactory sensitivity of the proposed method. Finally, the TFME-GC-MS method was successfully utilized for the measurement of PAEs in milk solutions and drinking water preserved in baby bottle with satisfactory relative recoveries (RRs) (88-101%) and relative standard deviations (RSDs) lower than 8.0% (n = 3). Totally, a simple, rapid, sensitive and highly efficient method was introduced to analyze trace PAEs in complex samples.


Assuntos
Ésteres/isolamento & purificação , Microextração em Fase Líquida/métodos , Leite/química , Nanofibras/química , Água/química , Aminofenóis/química , Animais , Caprolactama/análogos & derivados , Caprolactama/química , Ésteres/análise , Ésteres/química , Cromatografia Gasosa-Espectrometria de Massas , Grafite/química , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Ácidos Ftálicos/química , Polímeros/química , Poluentes Químicos da Água/análise
20.
Chemosphere ; 228: 390-397, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31048236

RESUMO

Sustainable bio nano composite comprising of nanoMgS/FeS doped cellulose nanofibres (FeMgSCNF) was prepared, characterized by various techniques and assessed for the decontamination of Cr(VI). Cellulose nanofibres (CNF) acts as a template and stabilizer and prevents agglomeration of FeS/MgS nano particles. MgS present in the nano-composite provides a barrier to suppress aerial oxidation of Fe(II) and provided additional source of sulfide ions. An adsorption capacity in the order of 142.8 mg/g of the bionano composite was exhibited towards hexavalent chromium. Both FeSCNF and FeMgSCNF followed pseudo first order and pseudo second order kinetics with regression coefficients >0.96. X-ray photoelectron spectroscopy (XPS) studies indicated that decontamination of Cr(VI) follows the route of electrostatic attraction, ion-exchange followed by reduction of Cr(VI) to Cr(III) and immobilization of Cr(III) as chromic oxide and Fe-Cr mixed oxide. Toxicity characteristics leaching tests revealed the efficacy of immobilization. Finally the developed sorbents were successfully applied to the removal of chromium from tannery waste effluents.


Assuntos
Celulose/química , Cromo/química , Descontaminação/métodos , Sulfato de Magnésio/química , Nanofibras/química
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