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1.
Nat Commun ; 11(1): 4465, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901012

RESUMO

Titanium implants have been widely used in bone tissue engineering for decades. However, orthopedic implant-associated infections increase the risk of implant failure and even lead to amputation in severe cases. Although TiO2 has photocatalytic activity to produce reactive oxygen species (ROS), the recombination of generated electrons and holes limits its antibacterial ability. Here, we describe a graphdiyne (GDY) composite TiO2 nanofiber that combats implant infections through enhanced photocatalysis and prolonged antibacterial ability. In addition, GDY-modified TiO2 nanofibers exert superior biocompatibility and osteoinductive abilities for cell adhesion and differentiation, thus contributing to the bone tissue regeneration process in drug-resistant bacteria-induced implant infection.


Assuntos
Antibacterianos/química , Grafite , Nanofibras/química , Próteses e Implantes , Infecções Relacionadas à Prótese/prevenção & controle , Titânio , Células 3T3 , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Teste de Materiais , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Nanocompostos/química , Osteogênese , Processos Fotoquímicos , Infecções Estafilocócicas/prevenção & controle
2.
Small ; 16(38): e2003010, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32815251

RESUMO

Currently, mesenchymal stem cells (MSCs)-based therapies for bone regeneration and treatments have gained significant attention in clinical research. Though many chemical and physical cues which influence the osteogenic differentiation of MSCs have been explored, scaffolds combining the benefits of Zn2+ ions and unique nanostructures may become an ideal interface to enhance osteogenic and anti-infective capabilities simultaneously. In this work, motivated by the enormous advantages of Zn-based metal-organic framework-derived nanocarbons, C-ZnO nanocarbons-modified fibrous scaffolds for stem cell-based osteogenic differentiation are constructed. The modified scaffolds show enhanced expression of alkaline phosphatase, bone sialoprotein, vinculin, and a larger cell spreading area. Meanwhile, the caging of ZnO nanoparticles can allow the slow release of Zn2+ ions, which not only activate various signaling pathways to guide osteogenic differentiation but also prevent the potential bacterial infection of implantable scaffolds. Overall, this study may provide new insight for designing stem cell-based nanostructured fibrous scaffolds with simultaneously enhanced osteogenic and anti-infective capabilities.


Assuntos
Carbono/química , Células-Tronco Mesenquimais/citologia , Nanofibras/química , Osteogênese/fisiologia , Tecidos Suporte/química , Óxido de Zinco/química , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Sialoproteína de Ligação à Integrina/metabolismo , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Nanofibras/ultraestrutura , Transdução de Sinais , Engenharia Tecidual , Vinculina/metabolismo
3.
Int J Nanomedicine ; 15: 4991-5004, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764931

RESUMO

Introduction: Various materials and approaches have been used to reduce the mesh-induced inflammatory response and modify the mesh with tissue-matched mechanical properties, aiming to improve the repair of abdominal wall defects. Materials and Methods: In this study, we fabricated a polycaprolactone (PCL)/silk fibroin (SF) mesh integrated with amoxicillin (AMX)-incorporating multiwalled carbon nanotubes (MWCNTs) via electrospinning, grafting and crosslinking, developing a sustainable antibiotic and flexible mesh. AMX was loaded into the hollow tubular MWCNTs by physical adsorption, and a nanofibrous structure was constructed by electrospinning PCL and SF (40:60 w/w). The AMX@MWCNTs were then chemically grafted onto the surfaces of the PCL/SF nanofibers by treating with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS) solution for simultaneous crosslinking and coating. The incorporation of AMX into the MWCNTs (AMX@MWCNTs) and the integration of the AMX@MWCNTs with the PCL/SF nanofibers were characterized. Then, the functional mesh was fabricated and fully evaluated in terms of antibacterial activity, mechanical properties and host response. Results: Our results demonstrated that the PCL/SF nanofibrous structure was fabricated successfully by electrospinning. After integrating with AMX@MWCNT by grafting and crosslinking, the functional mesh showed undeformed structure, modified surface hydrophilicity and biocompatible interfaces, abdominal wall-matched mechanical properties, and a sustained-release antibiotic profile in E. coli growth inhibition compared to those of PCL/SF mesh in vitro. In a rat model with subcutaneous implantation, the functional mesh incited less mesh-induced inflammatory and foreign body responses than PCL/SF mesh within 14 days. The histological analysis revealed less infiltration of granulocytes and macrophages during this period, resulting in the loosely packed collagen deposition on the functional mesh and prominent collagen incorporation. Discussion: Therefore, this designed PCL/SF-AMX@MWCNT nanofibrous mesh, functionalized with antibacterial and tissue-matched mechanical properties, provides a promising alternative for the repair of abdominal wall defects.


Assuntos
Amoxicilina/química , Antibacterianos/química , Nanofibras/química , Nanotecnologia/métodos , Telas Cirúrgicas , Amoxicilina/farmacocinética , Amoxicilina/farmacologia , Animais , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Colágeno/química , Colágeno/metabolismo , Reagentes para Ligações Cruzadas/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroínas/química , Inflamação/etiologia , Masculino , Teste de Materiais , Camundongos , Nanotubos de Carbono/química , Poliésteres/química , Ratos Sprague-Dawley , Telas Cirúrgicas/efeitos adversos
4.
Proc Natl Acad Sci U S A ; 117(32): 19201-19208, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32737162

RESUMO

As the hardest tissue formed by vertebrates, enamel represents nature's engineering masterpiece with complex organizations of fibrous apatite crystals at the nanometer scale. Supramolecular assemblies of enamel matrix proteins (EMPs) play a key role as the structural scaffolds for regulating mineral morphology during enamel development. However, to achieve maximum tissue hardness, most organic content in enamel is digested and removed at the maturation stage, and thus knowledge of a structural protein template that could guide enamel mineralization is limited at this date. Herein, by examining a gene-modified mouse that lacked enzymatic degradation of EMPs, we demonstrate the presence of protein nanoribbons as the structural scaffolds in developing enamel matrix. Using in vitro mineralization assays we showed that both recombinant and enamel-tissue-based amelogenin nanoribbons are capable of guiding fibrous apatite nanocrystal formation. In accordance with our understanding of the natural process of enamel formation, templated crystal growth was achieved by interaction of amelogenin scaffolds with acidic macromolecules that facilitate the formation of an amorphous calcium phosphate precursor which gradually transforms into oriented apatite fibers along the protein nanoribbons. Furthermore, this study elucidated that matrix metalloproteinase-20 is a critical regulator of the enamel mineralization as only a recombinant analog of a MMP20-cleavage product of amelogenin was capable of guiding apatite mineralization. This study highlights that supramolecular assembly of the scaffold protein, its enzymatic processing, and its ability to interact with acidic carrier proteins are critical steps for proper enamel development.


Assuntos
Amelogenina/química , Esmalte Dentário/metabolismo , Amelogênese , Amelogenina/metabolismo , Animais , Apatitas/química , Apatitas/metabolismo , Esmalte Dentário/química , Proteínas do Esmalte Dentário/química , Proteínas do Esmalte Dentário/metabolismo , Camundongos , Nanofibras/química
5.
Life Sci ; 258: 118152, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735881

RESUMO

AIMS: Cancer stem cells (CSCs) are the source of tumors and play a key role in the resistance of cancer to therapies. To improve the current therapies against CSCs, in this work we developed a novel system of electrospun polycaprolactone (PCL) nanofibers containing hydroxylated multi-walled carbon nanotubes (MWCNTs-OH) and all-trans retinoic acid (ATRA). MATERIALS AND METHODS: The nanofiber membranes were forged by electrospinning, and the physical and chemical properties of the nanofiber membranes were evaluated by scanning electron microscopy, XRD and Raman etc. The photothermal properties of nanofiber membranes and their effects on CSCs differentiation and cytotoxicity were investigated. Finally, the anti-tumor effect of nanofiber membranes in vivo was evaluated. KEY FINDINGS: The nanofibers formed under optimal conditions were smooth without beads. The nanofibrous membranes with MWCNTs-OH could increase temperature of the medium under near-infrared (NIR) illumination to suppress the viability of glioma stem cells (GSCs). Meanwhile, the added ATRA could further induce the differentiation of GSCs to destroy their stemness and reduce their resistance to heat treatment. Compared with no NIR irradiation, after 2min NIR irradiation, the membranes reduced the in-vitro viability of GSCs by 13.41%, 14.83%, and 26.71% after 1, 2, and 3 days, respectively. After 3 min daily illumination for 3 days, the viability of GSCs was only 22.75%, and similar results were observed in vivo. SIGNIFICANCE: These results showed efficiently cytotoxicity to CSCs by combining heat therapy and differentiation therapy. The nanofiber membranes if inserted at the site after surgical tumor removal, may hinder tumor recurrence.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/terapia , Glioma/terapia , Nanofibras/uso terapêutico , Células-Tronco Neoplásicas/efeitos dos fármacos , Tretinoína/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Glioma/patologia , Humanos , Hipertermia Induzida/métodos , Masculino , Camundongos Endogâmicos BALB C , Nanofibras/química , Nanotubos de Carbono/química , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Células-Tronco Neoplásicas/patologia , Poliésteres/química , Poliésteres/uso terapêutico , Tretinoína/administração & dosagem
6.
Int J Nanomedicine ; 15: 4021-4047, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606662

RESUMO

Purpose: Periodontitis is a chronic inflammatory disease associated with microbial accumulation. The purpose of this study was to reuse the agricultural waste to produce cellulose nanofibers (CNF) and further modification of the CNF with κ-carrageenan oligosaccharides (CO) for drug delivery. In addition, this study is focused on the antimicrobial activity of surfactin-loaded CO-CNF towards periodontal pathogens. Materials and Methods: A chemo-mechanical method was used to extract the CNF and the modification was done by using CO. The studies were further proceeded by adding different quantities of surfactin [50 mg (50 SNPs), 100 mg (100 SNPs), 200 mg (200 SNPs)] into the carrier (CO-CNF). The obtained materials were characterized, and the antimicrobial activity of surfactin-loaded CO-CNF was evaluated. Results: The obtained average size of CNF and CO-CNF after ultrasonication was 263 nm and 330 nm, respectively. Microscopic studies suggested that the CNF has a short diameter with long length and CO became cross-linked to form as beads within the CNF network. The addition of CO improved the degradation temperature, crystallinity, and swelling property of CNF. The material has a controlled drug release, and the entrapment efficiency and loading capacity of the drug were 53.15 ± 2.36% and 36.72 ± 1.24%, respectively. It has antioxidant activity and inhibited the growth of periodontal pathogens such as Streptococcus mutans and Porphyromonas gingivalis by preventing the biofilm formation, reducing the metabolic activity, and promoting the oxidative stress. Conclusion: The study showed the successful extraction of CNF and modification with CO improved the physical parameters of the CNF. In addition, surfactin-loaded CO-CNF has potential antimicrobial activity against periodontal pathogens. The obtained biomaterial is economically valuable and has great potential for biomedical applications.


Assuntos
Carragenina/química , Celulose/química , Lipopeptídeos/química , Nanofibras/química , Peptídeos Cíclicos/química , Periodonto/microbiologia , Animais , Bactérias/metabolismo , Compostos de Bifenilo/química , Sobrevivência Celular , Difusão Dinâmica da Luz , Depuradores de Radicais Livres/química , Malondialdeído/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Oligossacarídeos/química , Picratos/química , Células RAW 264.7 , Soja/química , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Nat Commun ; 11(1): 3541, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669562

RESUMO

Dynamic spatiotemporal patterns that arise from out-of-equilibrium biochemical reactions generate forces in living cells. Despite considerable recent efforts, rational design of spatiotemporal patterns in artificial molecular systems remains at an early stage of development. Here, we describe force generation by a propagating wave of supramolecular nanofibers. Inspired by actin dynamics, a reaction network is designed to control the formation and degradation of nanofibers by two chemically orthogonal stimuli. Real-time fluorescent imaging successfully visualizes the propagating wave based on spatiotemporally coupled generation and collapse of nanofibers. Numerical simulation indicates that the concentration gradient of degradation stimulus and the smaller diffusion coefficient of the nanofiber are critical for wave emergence. Moreover, the force (0.005 pN) generated by chemophoresis and/or depletion force of this propagating wave can move nanobeads along the wave direction.


Assuntos
Modelos Químicos , Nanofibras/química , Hidrogéis/química , Cinética , Fenômenos Mecânicos , Estrutura Molecular , Nanofibras/ultraestrutura , Espectroscopia de Prótons por Ressonância Magnética
8.
Int J Nanomedicine ; 15: 3903-3920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606657

RESUMO

Background: Researchers are trying to study the mechanism of neural stem cells (NSCs) differentiation to oligodendrocyte-like cells (OLCs) as well as to enhance the selective differentiation of NSCs to oligodendrocytes. However, the limitation in nerve tissue accessibility to isolate the NSCs as well as their differentiation toward oligodendrocytes is still challenging. Purpose: In the present study, a hybrid polycaprolactone (PCL)-gelatin nanofiber scaffold mimicking the native extracellular matrix and axon morphology to direct the differentiation of bone marrow-derived NSCs to OLCs was introduced. Materials and Methods: In order to achieve a sustained release of T3, this factor was encapsulated within chitosan nanoparticles and chitosan-loaded T3 was incorporated within PCL nanofibers. Polyaniline graphene (PAG) nanocomposite was incorporated within gelatin nanofibers to endow the scaffold with conductive properties, which resemble the conductive behavior of axons. Biodegradation, water contact angle measurements, and scanning electron microscopy (SEM) observations as well as conductivity tests were used to evaluate the properties of the prepared scaffold. The concentration of PAG and T3-loaded chitosan NPs in nanofibers were optimized by examining the proliferation of cultured bone marrow-derived mesenchymal stem cells (BMSCs) on the scaffolds. The differentiation of BMSCs-derived NSCs cultured on the fabricated scaffolds into OLCs was analyzed by evaluating the expression of oligodendrocyte markers using immunofluorescence (ICC), RT-PCR and flowcytometric assays. Results: Incorporating 2% PAG proved to have superior cell support and proliferation while guaranteeing electrical conductivity of 10.8 × 10-5 S/cm. Moreover, the scaffold containing 2% of T3-loaded chitosan NPs was considered to be the most biocompatible samples. Result of ICC, RT-PCR and flow cytometry showed high expression of O4, Olig2, platelet-derived growth factor receptor-alpha (PDGFR-α), O1, myelin/oligodendrocyte glycoprotein (MOG) and myelin basic protein (MBP) high expressed but low expression of glial fibrillary acidic protein (GFAP). Conclusion: Considering surface topography, biocompatibility, electrical conductivity and gene expression, the hybrid PCL/gelatin scaffold with the controlled release of T3 may be considered as a promising candidate to be used as an in vitro model to study patient-derived oligodendrocytes by isolating patient's BMSCs in pathological conditions such as diseases or injuries. Moreover, the resulted oligodendrocytes can be used as a desirable source for transplanting in patients.


Assuntos
Materiais Biomiméticos/farmacologia , Células da Medula Óssea/citologia , Diferenciação Celular , Nanofibras/química , Células-Tronco Neurais/citologia , Oligodendroglia/citologia , Tecidos Suporte/química , Compostos de Anilina/química , Animais , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condutividade Elétrica , Gelatina/química , Grafite/química , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/ultraestrutura , Células-Tronco Neurais/metabolismo , Oligodendroglia/efeitos dos fármacos , Poliésteres/química , Ratos , Suínos , Tri-Iodotironina/farmacologia
9.
PLoS One ; 15(7): e0235979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706773

RESUMO

Alzheimer's disease (AD) is proposed to be induced by abnormal aggregation of amyloidß in the brain. Here, we designed a brain-permeable peptide nanofiber drug from a fragment of heat shock protein to suppress aggregation of the pathogenic proteins. To facilitate delivery of the nanofiber into the brain, a protein transduction domain from Drosophila Antennapedia was incorporated into the peptide sequence. The resulting nanofiber efficiently suppressed the cytotoxicity of amyloid ßby trapping amyloid ß onto its hydrophobic nanofiber surface. Moreover, the intravenously or intranasally injected nanofiber was delivered into the mouse brain, and improved the cognitive function of an Alzheimer transgenic mouse model. These results demonstrate the potential therapeutic utility of nanofibers for the treatment of AD.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/administração & dosagem , Encéfalo/metabolismo , Modelos Animais de Doenças , Transtornos da Memória/prevenção & controle , Nanofibras/administração & dosagem , Placa Amiloide/prevenção & controle , Administração Intranasal , Doença de Alzheimer/etiologia , Doença de Alzheimer/patologia , Animais , Encéfalo/efeitos dos fármacos , Feminino , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Camundongos , Camundongos Transgênicos , Nanofibras/química , Placa Amiloide/etiologia , Placa Amiloide/patologia
10.
J Chromatogr A ; 1625: 461305, 2020 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-32709348

RESUMO

A novel kind of magnetic porous carbon nano-fibers (Fe3O4@P-CNFs) materials was successfully prepared and used as an adsorbent. Based on the above-mentioned adsorbent, a simple and effective magnetic disperse solid-phase extraction (MSPE) method was developed and first utilized to the enrichment and purification of five Sudan dyes (including Sudan I, Sudan II, Sudan III, Sudan IV, and Sudan Red 7B) in foodstuffs for the first time. High-performance liquid chromatography was used to determine the content of the Sudan dyes. The parameters affecting the extraction performance were studied and optimized, including the amount of the adsorbent and inorganic salt, type and the volume of the eluent, pH of the sample solution and extraction time. Under the optimized experimental conditions, the results show that the proposed method has a good linear relationship (r≥ 0.9993). The limits of detection range from 0.88 µg L-1 to 1.27 µg L-1. The recoveries range from 86.6% to 99.7% with the relative standard deviations ranging from 0.6% to 7.9% in the methodology validation. The above-mentioned results indicate that the proposed method is a sensitive and reliable procedure with good reproducibility for the detection of Sudan dyes residues in foodstuffs.


Assuntos
Compostos Azo/análise , Fibra de Carbono/química , Corantes/análise , Análise de Alimentos , Fenômenos Magnéticos , Nanofibras/química , Adsorção , Compostos Azo/química , Corantes/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanofibras/ultraestrutura , Porosidade , Análise de Regressão , Reprodutibilidade dos Testes , Sais/química , Fatores de Tempo
11.
Proc Natl Acad Sci U S A ; 117(25): 14602-14608, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32522869

RESUMO

Bioinspired actuators with stimuli-responsive and deformable properties are being pursued in fields such as artificial tissues, medical devices and diagnostics, and intelligent biosensors. These applications require that actuator systems have biocompatibility, controlled deformability, biodegradability, mechanical durability, and stable reversibility. Herein, we report a bionic actuator system consisting of stimuli-responsive genetically engineered silk-elastin-like protein (SELP) hydrogels and wood-derived cellulose nanofibers (CNFs), which respond to temperature and ionic strength underwater by ecofriendly methods. Programmed site-selective actuation can be predicted and folded into three-dimensional (3D) origami-like shapes. The reversible deformation performance of the SELP/CNF actuators was quantified, and complex spatial transformations of multilayer actuators were demonstrated, including a biomimetic flower design with selective petal movements. Such actuators consisting entirely of biocompatible and biodegradable materials will offer an option toward constructing stimuli-responsive systems for in vivo biomedicine soft robotics and bionic research.


Assuntos
Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Biônica/métodos , Celulose/química , Elastina/química , Elastina/genética , Hidrogéis/química , Conformação Molecular , Nanofibras/química , Engenharia de Proteínas , Robótica/métodos , Seda/química , Seda/genética
12.
Int J Nanomedicine ; 15: 3729-3740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547025

RESUMO

Background: Duraplasty is one of the most critical issues in neurosurgical procedures because the defect of dura matter will cause many complications. Electrospinning can mimic the 3D structure of the natural extracellular matrix whose structure is similar to that of dura matter. Poly(L-lactic acid) (PLLA) has been used to fabricate dura matter substitutes and showed compatibility to dural tissue. However, the mechanical properties of the PLLA substitute cannot match the mechanical properties of the human dura mater. Methods and Results: We prepared stereocomplex nanofiber membranes based on enantiomeric poly(lactic acid) and poly(D-lactic acid)-grafted tetracalcium phosphate via electrospinning. X-ray diffraction results showed the formation of stereocomplex crystallites (SC) in the composite nanofiber membranes. Scanning electron microscope observation images showed that composites nanofibers with higher SC formation can keep its original morphologies after heat treatment, suggesting the heat resistance of composite nanofiber membranes. Differential scanning calorimeter tests confirmed that the melting temperature of composite nanofiber membranes was approximately 222°C, higher than that of PLLA. Tensile testing indicated that the ultimate tensile strength and the elongation break of the stereocomplex nanofiber membranes were close to human dura matter. In vitro cytotoxicity studies proved that the stereocomplex nanofiber membranes were non-toxic. The neuron-like differentiation of marrow stem cells on the stereocomplex nanofiber membranes indicated its neuron compatibility. Conclusion: The stereocomplex nanofiber membranes have the potential to serve as a dura mater substitute.


Assuntos
Materiais Biomiméticos/química , Dura-Máter/fisiologia , Nanofibras/química , Poliésteres/química , Animais , Fosfatos de Cálcio/química , Varredura Diferencial de Calorimetria , Diferenciação Celular , Linhagem Celular , Cristalização , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos , Nanofibras/ultraestrutura , Neurônios/citologia , Ratos Sprague-Dawley , Estereoisomerismo , Temperatura , Difração de Raios X
13.
Int J Nanomedicine ; 15: 3511-3522, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547010

RESUMO

Introduction: Diabetic wounds are challenging to treat due to a wide range of pathophysiological changes. Hypoxia is one of the predominant contributing factors of poor vascularization and chronicity in diabetic wounds. This study was designed to develop polycaprolactone (PCL)-based oxygen-releasing electrospun wound dressings and evaluate their efficacy for improved full thickness wound healing in diabetic rats. Methods: PCL-based oxygen releasing wound dressings were made using electrospinning technology. The developed dressings were characterized in terms of physical as well as biological properties both in vitro and in vivo. E-spun nanofibrous dressings were physically characterized with scanning electron microscopy, Fourier-transform infrared spectroscopy, and Energy-dispersive X-ray spectroscopy. To study the likely impact of the fabricated wound dressings in hypoxic conditions, HIF-1α expression analysis was carried out both at gene and protein levels. Wound dressings were further evaluated for their healing potential for extensive wounds in diabetic rat models. Results: The experimental results showed that the developed dressings were capable of continuously generating oxygen for up to 10 days. Cell studies further confirmed pronounced expression of HIF-1α at gene and protein levels in cells seeded on PCL-sodium percarbonate (SPC) and PCL scaffolds compared with the cells cultured on a tissue culture plate. Chorioallantoic membrane assay revealed the supportive role of oxygen releasing dressings on angiogenesis compared to the control group. Histological assessment of the regenerated skin tissues proved that full thickness wounds covered with SPC loaded PCL dressings had a comparatively better vascularized and compact extracellular matrix with completely covered thick epithelium. Discussion: The developed oxygen generating polymeric nanofibrous wound dressings could potentially be used as an envisioned approach for the efficient recovery of chronic diabetic wounds.


Assuntos
Diabetes Mellitus/patologia , Nanofibras/química , Neovascularização Fisiológica/efeitos dos fármacos , Oxigênio/química , Poliésteres/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Bandagens , Bioensaio , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Nanofibras/ultraestrutura , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Pele/patologia , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Chemosphere ; 259: 127391, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32590176

RESUMO

Sodium dodecylbenzenesulfonate (SDBS) is commonly used to remove radioactive nuclides such as Cs ions during decontamination of shut-down nuclear power plants. Potential environmental problems still remain because of the incomplete removal of large amounts of SDBS from radioactive liquid waste. For the first time, mesoporous silica nanofibers (MSFs) were fabricated for an efficient SDBS separation. MSFs were prepared by electrospinning using tetraethyl orthosilicate, a surfactant, and a template polymer; the product had a large surface area, a high pore volume, and a uniform pore size distribution. The internal pores or external surface were modified with quaternary ammonium salt, providing affinity to water and an electrostatic interaction with SDBS. The MSF-based adsorbent had excellent adsorption ability for SDBS (158.98 mg/g) over conventional adsorbents. In addition, the MSF-based adsorbent could selectively adsorb SDBS from a mixed solution of SDBS and Cs ions. Judging from the Freundlich pseuso second-order kinetic adsorption, the adsorption isotherm indicated that the SDBS adsorption was a kind of multilayer physisorption.


Assuntos
Benzenossulfonatos/química , Césio/química , Poluentes Químicos da Água/química , Adsorção , Íons , Cinética , Nanofibras/química , Compostos de Amônio Quaternário , Dióxido de Silício/química , Tensoativos , Água
15.
J Chromatogr A ; 1622: 461098, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376014

RESUMO

In the current study, a novel covalent organic frameworks COF-SCU1 incorporated electrospun nanofibers (PAN@COF-SCU1 nanofibers) was fabricated via a facile electrospinning method and utilized as adsorbent in pipette tip solid-phase extraction (PT-SPE) of tetracycline antibiotics (TCs) from foods. The prepared PAN@COF-SCU1 nanofibers possessed both of the unique characteristics of electrospun nanofibers and COFS-CU1, and thus improving the adsorption capacity of the electrospun nanofibers and preventing the problems of leakage and high pressure caused by directly using the nanosize COFs as adsorbent in PT-SPE. The experiments affected the adsorption and desorption efficiencies, such as the loading ratios of COFS-CU1 in nanofibers, the amount of nanofibers, the matrix pH and desorption solvent, were studied in detail. Eventually, a new pipette tip solid-phase extraction-high performance liquid chromatography (PT-SPE/HPLC) method was proposed for the analysis of three TCs from food. Satisfied linearity for TCs was obtained in the range of 4-70 ng mL-1. The limits of detection and quantification were ranged from 0.6 to 3 ng mL-1 and from 2 to 10 ng mL-1, respectively. The interday and intraday precisions (RSD) were all lower than 9%. The proposed PT-SPE/HPLC method was used to determine TCs residues in grass carp and duck samples for the first time. The results could not only explore the availability of PT-SPE in the extraction of TCs in food samples, but also broadened the potential applications of COFs in sample preparation.


Assuntos
Carpas , Patos , Análise de Alimentos , Estruturas Metalorgânicas , Nanofibras , Extração em Fase Sólida , Tetraciclinas , Adsorção , Animais , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Análise de Alimentos/métodos , Estruturas Metalorgânicas/síntese química , Nanofibras/química , Tetraciclinas/isolamento & purificação
16.
Int J Nanomedicine ; 15: 2633-2646, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368045

RESUMO

Objective: The aim of this study is to fabricate functional scaffolds to gene delivery bone morphogenetic protein-2 (BMP-2) plasmid for bone formation in bone tissue engineering. Methods: Dendriplexes (DPs) of generation 4 polyamidoamin (G4-PAMAM)/BMP-2 plasmid were prepared through microfluidic (MF) platform. The physiochemical properties and toxicity of DPs were evaluated by DLS, AFM, FESEM and MTT assay. In order to create a suitable environment for stem cell growth and differentiation, poly-l-lactic acid (PLLA) and poly-l-lactic acid/poly (ethylene oxide) (PLLA/PEO) scaffolds containing hydroxyapatite nanoparticles (HA) and DPs were fabricated by the electrospinning method. The osteogenic potency of the scaffolds on human adipose tissue-derived mesenchymal stem cells (hASCs) was investigated. Results: The results revealed that tuning the physical properties of DPs by adjusting flow parameters in microfluidic platform can easily improve the cell viability compared to conventional bulk mixing method. Also, the result showed that the presence of HA and DPs in PLLA/PEO scaffold enhanced alkaline phosphatase (ALP) activity and increased the amount of deposited Ca, as well as, related to osteogenesis gen markers. Conclusion: This study indicated that on using the MF platform in preparation of DPs and loading them along with HA in PLLA/PEO scaffold, the osteogenic differentiation of hASCs could be tuned.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Osso e Ossos/fisiologia , Durapatita/química , Microfluídica , Nanofibras/química , Poliaminas/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Adesão Celular , Morte Celular , Diferenciação Celular , Proliferação de Células , Forma Celular , DNA/metabolismo , Dendrímeros/química , Humanos , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Tamanho da Partícula , Plasmídeos/metabolismo , Poliésteres/química , Resistência à Tração
17.
Nat Commun ; 11(1): 2405, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415064

RESUMO

Fiber-based electronics enabling lightweight and mechanically flexible/stretchable functions are desirable for numerous e-textile/e-skin optoelectronic applications. These wearable devices require low-cost manufacturing, high reliability, multifunctionality and long-term stability. Here, we report the preparation of representative classes of 3D-inorganic nanofiber network (FN) films by a blow-spinning technique, including semiconducting indium-gallium-zinc oxide (IGZO) and copper oxide, as well as conducting indium-tin oxide and copper metal. Specifically, thin-film transistors based on IGZO FN exhibit negligible performance degradation after one thousand bending cycles and exceptional room-temperature gas sensing performance. Owing to their great stretchability, these metal oxide FNs can be laminated/embedded on/into elastomers, yielding multifunctional single-sensing resistors as well as fully monolithically integrated e-skin devices. These can detect and differentiate multiple stimuli including analytes, light, strain, pressure, temperature, humidity, body movement, and respiratory functions. All of these FN-based devices exhibit excellent sensitivity, response time, and detection limits, making them promising candidates for versatile wearable electronics.


Assuntos
Nanopartículas Metálicas/química , Nanofibras/química , Dispositivos Eletrônicos Vestíveis , Consumo de Bebidas Alcoólicas , Técnicas Biossensoriais , Testes Respiratórios , Cobre/química , Elastômeros , Etanol/análise , Análise de Elementos Finitos , Gálio/química , Humanos , Índio/química , Teste de Materiais , Movimento (Física) , Poliestirenos/química , Semicondutores , Espectrofotometria Ultravioleta , Temperatura , Têxteis , Óxido de Zinco/química
18.
PLoS One ; 15(5): e0232851, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392238

RESUMO

Here we present the synthesis and characterization of two new conducting materials having a high electro-chemo-mechanical activity for possible applications as artificial muscles or soft smart actuators in biomimetic structures. Glucose-gelatin nanofiber scaffolds (CFS) were coated with polypyrrole (PPy) first by chemical polymerization followed by electrochemical polymerization doped with dodecylbenzensulfonate (DBS-) forming CFS-PPy/DBS films, or with trifluoromethanesulfonate (CF3SO3-, TF) giving CFS-PPy/TF films. The composition, electronic and ionic conductivity of the materials were determined using different techniques. The electro-chemo-mechanical characterization of the films was carried out by cyclic voltammetry and square wave potential steps in bis(trifluoromethane)sulfonimide lithium solutions of propylene carbonate (LiTFSI-PC). Linear actuation of the CFS-PPy/DBS material exhibited 20% of strain variation with a stress of 0.14 MPa, rather similar to skeletal muscles. After 1000 cycles, the creeping effect was as low as 0,2% having a good long-term stability showing a strain variation per cycle of -1.8% (after 1000 cycles). Those material properties are excellent for future technological applications as artificial muscles, batteries, smart membranes, and so on.


Assuntos
Órgãos Artificiais , Materiais Biomiméticos , Materiais Revestidos Biocompatíveis/química , Nanofibras , Polímeros/química , Pirróis/química , Tecidos Suporte , Benzenossulfonatos/química , Condutividade Elétrica , Eletroquímica , Gelatina/química , Glucose/química , Mesilatos/química , Microscopia Eletrônica de Varredura , Músculos , Nanofibras/química , Nanofibras/ultraestrutura , Polimerização , Potenciometria , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de Superfície , Tecidos Suporte/química
19.
Food Chem ; 328: 126768, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32470772

RESUMO

A colorimetric pH indicator was developed using nanofibers of poly(lactic acid) (PLA) and polyethylene oxide (PEO) combined with biomass of the microalga Spirulina sp. LEB 18. This study evaluates the potential use of microalgal biomass encapsulated in polymer nanofibers to develop a colorimetric pH indicator. Nanofibers containing the biomass were exposed to solutions with different pH values (pH 1-10), and color variations were measured using a colorimeter. The wettability analysis of the nanofibers showed hydrophilicity (zero angle with water), which allows ions to interact with the biomass, indicating a fast color response as a function of pH. When subjected to pH variations, indicators containing 1, 2 or 3% (w v-1) of biomass provided ΔΕ values >12, indicating an absolute difference in color. Therefore, this innovative material has the potential to be applied as a intelligent indicator to verify food quality through a visual signal of the product condition.


Assuntos
Colorimetria/métodos , Nanofibras/química , Spirulina/fisiologia , Biomassa , Cor , Concentração de Íons de Hidrogênio , Poliésteres/química , Polietilenoglicóis/química , Molhabilidade
20.
Food Chem ; 328: 127097, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32470774

RESUMO

In this study, polyaniline modified polyacrylonitrile nanofibers mat (PANI NFsM) was prepared as a novel adsorbent for the solid-phase extraction (SPE) of non-steroidal anti-inflammatory drug residues in meat or egg samples. The solvent extracts of samples were simply diluted with water to perform the SPE, and then the eluent was directly analyzed. Significant reduction of the matrix effect was obtained after SPE using only 5 mg of PANI NFsM. The entire sample preparation time is 5-10 times lower than the existing methods. The limits of detection of the target analytes ranging from 0.6 to 12.2 µg kg-1 had already met the demand of food safety monitoring by only 1 g sample. The recoveries ranged from 85.18% to 107.31%, with the intra-day and inter-day relative standard deviations of 2.74% to 16.01%, revealing satisfactory accuracy and precision. Finally, real samples analyses were applied to verify the practicability of the method.


Assuntos
Compostos de Anilina/química , Ração Animal/análise , Resíduos de Drogas/análise , Resíduos de Drogas/isolamento & purificação , Nanofibras/química , Extração em Fase Sólida/métodos , Resinas Acrílicas/química , Animais , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/isolamento & purificação , Química Verde , Limite de Detecção , Fatores de Tempo
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