这项工作是从内布拉斯加医疗中心和美国国立卫生研究院（授权号1R15 AR063901-01）大学的启动资金部分支持。

1.溶液的制备<ol><li>在100毫克/毫升的近似浓度制备的聚（ε -己内酯）（PCL）（M W =80000克/摩尔）的溶液中。以4:1的比例溶解的PCL在二氯甲烷（DCM）和N，N-二dimethlyformamide酰胺（DMF）的混合物:1（V / V）的10％的浓度（重量/体积）。 </li><li>放置在20毫升玻璃试管中的溶液混合。放置玻璃管入超声波清洗30分钟，或直到溶液是半透明的。 </li></ol> 2.设备准备<ol><li>加入制备的PCL溶液加到5毫升注射器附有一个21号钝针头。 </li><li>放置注射器泵在上下电纺丝位置，根据图1。 </li><li>使用的不锈钢集电极间隙为2厘米×5厘米为对齐纤维衬底上的开放空间。放置集电极从针尖端12公分。 </li><li>连接的直流（DC）高压电源向针和接地收藏家。确保集电极分别与没有接触到其他实验室设备接地。 </li></ol> 3.静电<ol><li>组注射泵至1.50毫升/小时，直到在针尖形成液滴除去时立即更换。然后，设置流速0.50毫升/小时。 </li><li>关闭电压操作员12千伏。 </li><li>静电纺丝直到单轴排列的纤维完全覆盖在收集器的间隙。 </li><li>应用胶水小玻璃板的边缘，并从该间隙集电极转移纤维玻璃板。放置在玻璃板上的一块铝箔具有相同的尺寸的玻璃板上，并接地的顶部。 </li><li>根据图3的位置第二注射器收集器。 </li><li>附加塑料掩模到第二注射器泵和位置它2毫米集电极上方。 </li><li>添加香豆素6在1％（W / W）至PCL溶液，如果楠oencapsulation是desired-并混合直到溶液是半透明的。 </li><li>加载PCL或PCL /香豆素6溶液到5ml针的钝21号针头。设置立式泵至0.50毫升/小时和水平拉以9ml / hr或以1mm /分钟的近似速度。 </li><li>静电纺丝直到掩模已经移动几乎完全关闭的集，但与边缘区域仍掩模之下。 </li></ol> 4.光纤鉴定<ol><li>将样品用双面导电胶带到金属螺栓和外套与铂为40秒，用溅射涂布机，在40毫安。 <ol><li>根据我们以前的研究17,18检查通过扫描电子显微镜（SEM）的纤维。 </li><li>在15千伏的加速电压采集图像。 </li></ol></li><li>执行在一个单独的纤维样本的快速傅立叶变换（FFT）分析，以测量纤维取向。在测量光纤对准了FFT的详细信息，可以参考吨Ø以往的研究19,20。 </li></ol> 5.播种的干细胞。 <ol><li>通过浸泡在2小时的70％的乙醇溶液消毒的纤维样品。然后洗涤该纤维用蒸馏水以除去任何污染物。 </li><li>在95％空气/ 5％CO 2的气氛中获得人脂肪干细胞和培养细胞中的25cm 2烧瓶中，在37℃。每隔10天改变细胞培养基。 </li><li> Trypsinize细胞并计数细胞的数目。具体而言，除去从细胞培养烧瓶中的所有培养基并用磷酸盐缓冲盐水（PBS）洗细胞两次。然后加入1 M L的0.25％胰蛋白酶-EDTA溶液（预温水浴中以37℃），以覆盖细胞单层并孵育在所述细胞培养孵化器的烧瓶中2-3分钟。加入4毫升培养介质和洗出从表面所有单元吹打的介质在整个表面。离心细胞悬浮液，并再分散第ë细胞沉淀在培养基中。算上通过血球细胞。约1×10 4个细胞的纳米纤维支架放置在35毫米的培养皿-文化和种子孵育3和7天。 </li><li>使用荧光素二乙酸酯（5毫克/毫升的丙酮）（FDA）的图像，然后使用荧光显微镜的样品染色的细胞。具体来说，加100微升的FDA解决培养皿和孵育30分钟。前三次荧光成像洗涤细胞，用PBS。通过基于我们以往的研究10定制垫实验室程序分析细胞方向。 </li></ol>

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The authors have nothing to disclose.

The most critical part of the protocol is generation of the gradient scaffold. It is imperative that the mask covering the collector moves at a constant velocity so there is a gradual change within the fiber scaffold. The correct preparation of PCL solution is also important to ensure electrospinning success. Checking the fiber morphology prior to electrospinning is recommendable, especially after the encapsulation of Coumarin-6, which may require a higher voltage to electrospin correctly. 
Fu...

纳米纤维，因为它们以模仿细胞外基质的结构和相对大小1能力用于组织工程一种流行工具。然而，一些天然组织界面，如腱-骨插入位点，含有胶原纤维，其显示出一个可变的组织结构，增加在对准朝向腱并降低在骨部位2-5。因此，对于有效的组织再生，有必要以制造支架，可以有效地模拟这种结构梯度。 在纤维组合物中的逐渐变化进行以前，已经研究，具体而言，矿物质含量6。然而，重建结缔组织的结构成分在很大程度上仍然未开发。早期的研究调查形态梯度通过研究大鼠颅骨成骨细胞的增殖表面的二氧化硅粒子密度的影响，并发现了一个INVER硅石颗粒密度和细胞增殖7之间本身关系。但介导的细胞增殖前期工作的形态变化，多与表面粗糙度缺乏模仿纤维组织变革7,8的能力。最近的一项研究试图制造的支架，通过使用一种新的收集器，用于电纺丝9模仿的独特胶原纤维取向。虽然本研究成功地制造与两个对准的和随机的纤维的支架，它未能模仿呈现在天然组织中的逐渐变化。另外，在产生了独立的部件，具有从对齐无规取向立即改变，这支架的生物力学特性显著降低。以前没有工作，已经能够生产出适用的纳米纤维支架与对齐和随机连续渐变的纤维取向。我们最近的研究表明纳米纤维支架的成功娱乐在纤维组织层次可以潜在模拟天然胶原组织在腱-骨插入10。这项工作的目的是提出用于生产纳米纤维支架的带结构非常类似于该纤维组织的在天然腱 - 骨组织界面的协议。 梯度纳米纤维结构都可能产生深远跨越各种领域的应用程序。我们集中在应用到腱-骨插入部位的组织工程用脂肪来源的干细胞（ADSC中），它们已经用于组织再生在各种基材上11-14结合我们的支架。此外，脂肪干细胞在性质上骨髓干细胞非常相似于多能的术语和其资源丰富，可以用一个简单的吸脂过程15,16收获。播种这些细胞渐变纳米纤维支架进一步增强他们的那朵通过允许所述细胞可以潜在分化成各种组织的受控分布告工程应用。除了接种干细胞，纳米纤维可以被封装与信号分子对细胞响应的调节。耦合nanoencapsulation这些支架的组织梯度允许的细胞行为或可能的植入物的设计和涂料的研究。的官能分子，如骨形态发生蛋白2（BMP2），这已被证明是诱导成骨细胞分化15,16，封装可以进一步提高这些支架10的组织工程应用。

<table><tbody><tr><td>Polycaprolactone</td><td>Sigma-Aldrich</td><td>440744</td><td></td></tr><tr><td>N,N-Dimethlyformamide</td><td>Fisher Chemical</td><td>D-119-1</td><td></td></tr><tr><td>Dichloromethane</td><td>Fisher Chemical</td><td>AC61093-1000</td><td></td></tr><tr><td>Coumarin 6</td><td>Sigma-Aldrich</td><td>546283</td><td></td></tr><tr><td>Adipose Derived Stem Cells</td><td>Cellular engineering Technologies</td><td>HMSC.AD-100</td><td></td></tr><tr><td>Fetal Bovine Serum</td><td>Life Technologies</td><td>26140-111</td><td></td></tr><tr><td>Fluorescein Diacetate</td><td>Sigma-Aldrich</td><td>F7378</td><td></td></tr><tr><td>Ethanol</td><td>Sigma-Aldrich</td><td>E7023</td><td></td></tr><tr><td>Trypsin-EDTA</td><td>Invitrogen</td><td>25300-054</td><td></td></tr><tr><td>&amp;alpha;-Modified Eagle&#039;s Medium</td><td>Invitrogen</td><td>a10490-01</td><td></td></tr><tr><td>Acetone</td><td>Fisher Scientific</td><td>s25120a</td><td></td></tr><tr><td>Phosphate Buffered Saline</td><td>Invitrogen</td><td>10010023</td><td></td></tr><tr><td>Glass Slides</td><td>VWR international, LLC</td><td>101412-842</td><td></td></tr><tr><td>Syringe Pump</td><td>Fisher Scientific</td><td>14-831-200</td><td>Single syringe</td></tr><tr><td>Ultrasonic Cleaner</td><td>Branson</td><td>1510</td><td></td></tr><tr><td>High Voltage DC Power Supply</td><td>Gamma High Voltage Research</td><td>ES30</td><td></td></tr><tr><td>Scanning Electron Microscope</td><td>FEI</td><td>Nova 2300</td><td></td></tr><tr><td>Fluorescence Microscope</td><td>Zeiss</td><td>Axio Imager 2</td><td></td></tr></tbody></table>

electrospun nanofiber scaffolds with gradations in fiber organization

The goal of this protocol is to report a simple method for generating nanofiber scaffolds with gradations in fiber organization and test their possible applications in controlling cell morphology/orientation. Nanofiber organization is controlled with a new fabrication apparatus that enables the gradual decrease of fiber organization in a scaffold. Changing the alignment of fibers is achieved through decreasing deposition time of random electrospun fibers on a uniaxially aligned fiber mat. By covering the collector with a moving barrier/mask, along the same axis as fiber deposition, the organizational structure is easily controlled. For tissue engineering purposes, adipose-derived stem cells can be seeded to these scaffolds. Stem cells undergo morphological changes as a result of their position on the varied organizational structure, and can potentially differentiate into different cell types depending on their locations. Additionally, the graded organization of fibers enhances the biomimicry of nanofiber scaffolds so they more closely resemble the natural orientations of collagen nanofibers at tendon-to-bone insertion site compared to traditional scaffolds. Through nanoencapsulation, the gradated fibers also afford the possibility to construct chemical gradients in fiber scaffolds, and thereby further strengthen their potential applications in fast screening of cell-materials interaction and interfacial tissue regeneration. This technique enables the production of continuous gradient scaffolds, but it also can potentially produce fibers in discrete steps by controlling the movement of the moving barrier/mask in a discrete fashion.

使用该协议，形成纤维垫与组织梯度。 图3示出了在对纳米纤维支架的不同位置拍摄的SEM图像。定性，可以判断为存在来自单轴排列的纤维，在0毫米（ 图3A）到一个随机纤维品种在6毫米（ 图3D）一个进展。在FFT给出的定量值对纤维取向，在定量过程细节详见这里19。纤维在0毫米展品的FFT表示纤维取向，并以6毫米的FFT模式表示一个随机的取向。有一个...

Watch this Scientific Journal Video about Electrospun Nanofiber Scaffolds with Gradations in Fiber Organization at JoVE.com

Electrospun Nanofiber Scaffolds with Gradations in Fiber Organization

在这里，我们提出了一个协议，以制造静电纳米纤维支架与纤维的顺层组织，并探索在调节细胞形态/定位他们的应用程序。梯度对于纳米纤维支架的物理和化学性质提供了各种各样的在生物医学领域的应用程序。

静电纳米纤维支架与渐变的纤维组织

The goal of this protocol is to report a simple method for generating nanofiber scaffolds with gradations in fiber organization and test their possible ...

electrospun-nanofiber-scaffolds-with-gradations-in-fiber-organization

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Bioengineering

9.8K 次观看.  University of Nebraska Medical Center. 在这里，我们提出了一个协议，以制造静电纳米纤维支架与纤维的顺层组织，并探索在调节细胞形态/定位他们的应用程序。梯度对于纳米纤维支架的物理和化学性质提供了各种各样的在生物医学领域的应用程序。 

视频: Electrospun Nanofiber Scaffolds with Gradations in Fiber Organization

Electrospinning Fundamentals: Optimizing Solution and Apparatus Parameters

Electrospun nanofiber scaffolds have been shown to accelerate the maturation, improve the growth, and direct the migration of cells in vitro. Electrospinning is a process in which a charged polymer jet is collected on a grounded collector; a rapidly rotating collector results in aligned nanofibers while stationary collectors result in randomly oriented fiber mats. The polymer jet is formed when an applied electrostatic charge overcomes the surface tension of the solution. There is a minimum concentration for a given polymer, termed the critical entanglement concentration, below which a stable jet cannot be achieved and no nanofibers will form - although nanoparticles may be achieved (electrospray). A stable jet has two domains, a streaming segment and a whipping segment. While the whipping jet is usually invisible to the naked eye, the streaming segment is often visible under appropriate lighting conditions. Observing the length, thickness, consistency and movement of the stream is useful to predict the alignment and morphology of the nanofibers being formed. A short, non-uniform, inconsistent, and/or oscillating stream is indicative of a variety of problems, including poor fiber alignment, beading, splattering, and curlicue or wavy patterns. The stream can be optimized by adjusting the composition of the solution and the configuration of the electrospinning apparatus, thus optimizing the alignment and morphology of the fibers being produced. In this protocol, we present a procedure for setting up a basic electrospinning apparatus, empirically approximating the critical entanglement concentration of a polymer solution and optimizing the electrospinning process. In addition, we discuss some common problems and troubleshooting techniques.

Electrospinning techniques can create a variety of nanofibrous scaffolds for tissue engineering or other applications. We describe here a procedure to optimize the parameters of the electrospinning solution and apparatus to obtain fibers with the desired morphology and alignment. Common problems and troubleshooting techniques are also presented.

静电基础：优化解决方案和设备参数

Electrospun nanofiber scaffolds have been shown to accelerate the maturation, improve the growth, and direct the migration of cells in vitro. ...

科研

生物工程

The Culture of Primary Motor and Sensory Neurons in Defined Media on Electrospun Poly-L-lactide Nanofiber Scaffolds

Electrospinning is a technique for producing micro- to nano-scale fibers. Fibers can be electrospun with varying degrees of alignment, from highly aligned to completely random. In addition, fibers can be spun from a variety of materials, including biodegradable polymers such as poly-L-lactic acid (PLLA). These characteristics make electrospun fibers suitable for a variety of scaffolding applications in tissue engineering. Our focus is on the use of aligned electrospun fibers for nerve regeneration. We have previously shown that aligned electrospun PLLA fibers direct the outgrowth of both primary sensory and motor neurons in vitro. We maintain that the use of a primary cell culture system is essential when evaluating biomaterials to model real neurons found in vivo as closely as possible. Here, we describe techniques used in our laboratory to electrospin fibrous scaffolds and culture dorsal root ganglia explants, as well as dissociated sensory and motor neurons, on electrospun scaffolds. However, the electrospinning and/or culture techniques presented here are easily adapted for use in other applications.

Aligned electrospun fibers direct the growth of neurons in vitro and are a potential component of nerve regeneration scaffolds. We describe a procedure for preparing electrospun fiber substrates and the serum-free culture of primary rat E15 sensory (DRG) and motor neurons. Visualization of neurons by immunocytochemistry is also included.

初级运动和感觉神经元上的静电聚- L -乳酸纳米纤维支架中定义的媒体文化

Electrospinning is a technique for producing micro- to nano-scale fibers. Fibers can be electrospun with varying degrees of alignment, from highly aligned ...

神经科学

Postproduction Processing of Electrospun Fibres for Tissue Engineering

Electrospinning is a commonly used and versatile method to produce scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo undergo biaxial distension to varying extents such as skin, bladder, pelvic floor and even the hard palate as children grow. In producing scaffolds for these purposes there is a need to develop scaffolds of appropriate biomechanical properties (whether achieved without or with cells) and which are sterile for clinical use. The focus of this paper is not how to establish basic electrospinning parameters (as there is extensive literature on electrospinning) but on how to modify spun scaffolds post production to make them fit for tissue engineering purposes - here thickness, mechanical properties and sterilisation (required for clinical use) are considered and we also describe how cells can be cultured on scaffolds and subjected to biaxial strain to condition them for specific applications.
Electrospinning tends to produce thin sheets; as the electrospinning collector becomes coated with insulating fibres it becomes a poor conductor such that fibres no longer deposit on it. Hence we describe approaches to produce thicker structures by heat or vapour annealing increasing the strength of scaffolds but not necessarily the elasticity. Sequential spinning of scaffolds of different polymers to achieve complex scaffolds is also described. Sterilisation methodologies can adversely affect strength and elasticity of scaffolds. We compare three methods for their effects on the biomechanical properties on electrospun scaffolds of poly lactic-co-glycolic acid (PLGA).
Imaging of cells on scaffolds and assessment of production of extracellular matrix (ECM) proteins by cells on scaffolds is described. Culturing cells on scaffolds in vitro can improve scaffold strength and elasticity but the tissue engineering literature shows that cells often fail to produce appropriate ECM when cultured under static conditions. There are few commercial systems available that allow one to culture cells on scaffolds under dynamic conditioning regimes - one example is the Bose Electroforce 3100 which can be used to exert a conditioning programme on cells in scaffolds held using mechanical grips within a media filled chamber.4 An approach to a budget cell culture bioreactor for controlled distortion in 2 dimensions is described. We show that cells can be induced to produce elastin under these conditions. Finally assessment of the biomechanical properties of processed scaffolds cultured with or without cells is described.

Electrospun scaffolds can be processed post production for tissue engineering applications. Here we describe methods for spinning complex scaffolds (by consecutive spinning), for making thicker scaffolds (by multi-layering using heat or vapour annealing), for achieving sterility (aseptic production or sterilisation post production) and for achieving appropriate biomechanical properties.

静电纤维组织工程的后期处理

Electrospinning is a commonly used and versatile method to produce  scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo ...

Expansion of Two-dimension Electrospun Nanofiber Mats into Three-dimension Scaffolds

Electrospinning has been the preferred technology in producing a synthetic, functional scaffold due to the biomimicry to extracellular matrix and the ease control of composition, structure, and diameter of fibers. However, despite these advantages, traditional electrospun nanofiber scaffolds come with limitations including disorganized nanofiber orientation, low porosity, small pore size, and mainly two-dimensional mats. As such, there is a great need for developing a new process for fabricating electrospun nanofiber scaffolds that can overcome the above limitations. Herein, a novel and simple method is outlined. A traditional 2D nanofiber mat is transformed into a 3D scaffold with desired thickness, gap distance, porosity, and nanotopographic cues to allow for cell seeding and proliferation through the depressurization of subcritical CO2 fluid. In addition to providing a scaffold for tissue regeneration to occur, this method also provides the opportunity to encapsulate bioactive molecules such as antimicrobial peptides for local drug delivery. The CO2 expanded nanofiber scaffolds hold great potential in tissue regeneration, wound healing, 3D tissue modeling, and topical drug delivery.

This article demonstrates the technique of expanding a traditional, two-dimension (2D) electrospun nanofiber mat into a three-dimension (3D) scaffold through the depressurization of subcritical CO2 fluid. These augmented scaffolds are 3D, closely mimic cellular nanotopographic cues, and preserve the functions of biologic molecules encapsulated within the nanofibers.

将二维电纺纳米纤维垫扩展到三维支架中

Electrospinning has been the preferred technology in producing a synthetic, functional scaffold due to the biomimicry to extracellular matrix and the ease ...

遗传学

Self-reporting Scaffolds for 3-Dimensional Cell Culture

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting 3D cellular construct can often be more relevant to studying the molecular events and cell-cell interactions than similar experiments studied in 2D. To create effective 3D cultures with high cell viability throughout the scaffold the culture conditions such as oxygen and pH need to be carefully controlled as gradients in analyte concentration can exist throughout the 3D construct. Here we describe the methods of preparing biocompatible pH responsive sol-gel nanosensors and their incorporation into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds along with their subsequent preparation for the culture of mammalian cells. The pH responsive scaffolds can be used as tools to determine microenvironmental pH within a 3D cellular construct. Furthermore, we detail the delivery of pH responsive nanosensors to the intracellular environment of mammalian cells whose growth was supported by electrospun PLGA scaffolds. The cytoplasmic location of the pH responsive nanosensors can be utilized to monitor intracellular pH (pHi) during ongoing experimentation.

Biocompatible pH responsive sol-gel nanosensors can be incorporated into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds. The produced self-reporting scaffolds can be used for in&#160;situ monitoring of microenvironmental conditions whilst culturing cells upon the scaffold. This is beneficial as the 3D cellular construct can be monitored in real-time without disturbing the experiment.

自我报告的支架3维细胞培养

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting ...

ECM Protein Nanofibers and Nanostructures Engineered Using Surface-initiated Assembly

The extracellular matrix (ECM) in tissues is synthesized and assembled by cells to form a 3D fibrillar, protein network with tightly regulated fiber diameter, composition and organization. In addition to providing structural support, the physical and chemical properties of the ECM play an important role in multiple cellular processes including adhesion, differentiation, and apoptosis. In vivo, the ECM is assembled by exposing cryptic self-assembly (fibrillogenesis) sites within proteins. This process varies for different proteins, but fibronectin (FN) fibrillogenesis is well-characterized and serves as a model system for cell-mediated ECM assembly. Specifically, cells use integrin receptors on the cell membrane to bind FN dimers and actomyosin-generated contractile forces to unfold and expose binding sites for assembly into insoluble fibers. This receptor-mediated process enables cells to assemble and organize the ECM from the cellular to tissue scales. Here, we present a method termed surface-initiated assembly (SIA), which recapitulates cell-mediated matrix assembly using protein-surface interactions to unfold ECM proteins and assemble them into insoluble fibers. First, ECM proteins are adsorbed onto a hydrophobic polydimethylsiloxane (PDMS) surface where they partially denature (unfold) and expose cryptic binding domains. The unfolded proteins are then transferred in well-defined micro- and nanopatterns through microcontact printing onto a thermally responsive poly(N-isopropylacrylamide) (PIPAAm) surface. Thermally-triggered dissolution of the PIPAAm leads to final assembly and release of insoluble ECM protein nanofibers and nanostructures with well-defined geometries. Complex architectures are possible by engineering defined patterns on the PDMS stamps used for microcontact printing. In addition to FN, the SIA process can be used with laminin, fibrinogen and collagens type I and IV to create multi-component ECM nanostructures. Thus, SIA can be used to engineer ECM protein-based materials with precise control over the protein composition, fiber geometry and scaffold architecture in order to recapitulate the structure and composition of the ECM in vivo.

A method to obtain nanofibers and complex nanostructures from single or multiple extracellular matrix proteins is described. This method uses protein-surface interactions to create free-standing protein-based materials with tunable composition and architecture for use in a variety of tissue engineering and biotechnology applications.

细胞外基质蛋白纳米纤维和纳米结构工程采用表面引发大会

The extracellular matrix (ECM) in tissues is synthesized and assembled by cells to form a 3D fibrillar, protein network with tightly regulated fiber ...

Electrospinning Growth Factor Releasing Microspheres into Fibrous Scaffolds

This procedure describes a method to fabricate a multifaceted substrate to direct nerve cell growth. This system incorporates mechanical, topographical, adhesive and chemical signals. Mechanical properties are controlled by the type of material used to fabricate the electrospun fibers. In this protocol we use 30% methacrylated Hyaluronic Acid (HA), which has a tensile modulus of ~500 Pa, to produce a soft fibrous scaffold. Electrospinning on to a rotating mandrel produces aligned fibers to create a topographical cue. Adhesion is achieved by coating the scaffold with fibronectin. The primary challenge addressed herein is providing a chemical signal throughout the depth of the scaffold for extended periods. This procedure describes fabricating&#160;poly(lactic-co-glycolic acid) (PLGA) microspheres that contain Nerve Growth Factor (NGF) and directly impregnating the scaffold with these microspheres during the electrospinning process. Due to the harsh production environment, including high sheer forces and electrical charges, protein viability is measured after production. The system provides protein release for over 60 days and has been shown to promote primary nerve cell growth.

This protocol combines electrospinning and microspheres to develop tissue engineered scaffolds to direct neurons. Nerve growth factor was encapsulated within PLGA microspheres and electrospun into Hyaluronic Acid (HA) fibrous scaffolds. The protein bioactivity was tested by seeding the scaffolds with primary chick Dorsal Root Ganglia and culturing for 4-6 days.

静电生长因子释放到微纤维支架

This procedure describes a method to fabricate a multifaceted substrate to direct nerve cell growth.  This system incorporates mechanical, topographical, ...

Electrospun Fibrous Scaffolds of Poly(glycerol-dodecanedioate) for Engineering Neural Tissues From Mouse Embryonic Stem Cells

For tissue engineering applications, the preparation of biodegradable and biocompatible scaffolds is the most desirable but challenging task. &#160;Among the various fabrication methods, electrospinning is the most attractive one due to its simplicity and versatility. Additionally, electrospun nanofibers mimic the size of natural extracellular matrix ensuring additional support for cell survival and growth. This study showed the viability of the fabrication of long fibers spanning a larger deposit area for a novel biodegradable and biocompatible polymer named&#160;poly(glycerol-dodecanoate) (PGD)1 by using a newly designed collector for electrospinning. PGD exhibits unique elastic properties with similar mechanical properties to nerve tissues, thus it is suitable for neural tissue engineering applications. The synthesis and fabrication set-up for making fibrous scaffolding materials was simple, highly reproducible, and inexpensive. In biocompatibility testing, cells derived from mouse embryonic stem cells could adhere to and grow on the electrospun PGD fibers. In summary, this protocol provided a versatile fabrication method for making PGD electrospun fibers to support the growth of mouse embryonic stem cell derived neural lineage cells.

Electrospun Fibrous Scaffolds of Polyglycerol-dodecanedioate for Engineering Neural Tissues From Mouse Embryonic Stem Cells

Synthesis and fabrication of electrospun long fibers spanning a larger deposit area via a newly designed collector from a novel biodegradable polymer named poly(glycerol-dodecanoate) (PGD) was reported. The fibers were able to support the growth of cells derived from mouse pluripotent stem cells.

保利的静电纤维支架（甘油 - 十二双）工程神经组织从小鼠胚胎干细胞

For tissue engineering applications, the preparation of biodegradable and biocompatible scaffolds is the most desirable but challenging task. &#160;Among ...

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to intrinsic parameters within the process allow a high degree of control over scaffold characteristics including fiber diameter, alignment and porosity. By developing scaffolds with similar dimensions and topographies to organ- or tissue-specific extracellular matrices (ECM), micro-environments representative to those that cells are exposed to in situ can be created. 
The airway bronchiole wall, comprised of three main micro-environments, was selected as a model tissue. Using decellularized airway ECM as a guide, we electrospun the non-degradable polymer, polyethylene terephthalate (PET), by three different protocols to produce three individual electrospun scaffolds optimized for epithelial, fibroblast or smooth muscle cell-culture. Using a commercially available bioreactor system, we stably co-cultured the three cell-types to provide an in vitro model of the airway wall over an extended time period.
This model highlights the potential for such methods being employed in in vitro diagnostic studies investigating important inter-cellular cross-talk mechanisms or assessing novel pharmaceutical targets, by providing a relevant platform to allow the culture of fully differentiated adult cells within 3D, tissue-specific environments.

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Advancements in biomaterial technologies enable the development of three-dimensional multi-cell-type constructs. We have developed electrospinning protocols to produce three individual scaffolds to culture the main structural cells of the airway to provide a 3D in vitro model of the airway bronchiole wall.

适应静电过程中提供三个独特的环境为一个三层次<em&gt;在体外</em&gt;的气道壁模型

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to ...

Electrospinning Fibrous Polymer Scaffolds for Tissue Engineering and Cell Culture

As the field of tissue engineering evolves, there is a tremendous demand to produce more suitable materials and processing techniques in order to address the requirements (e.g., mechanics and vascularity) of more intricate organs and tissues. Electrospinning is a popular technique to create fibrous scaffolds that mimic the architecture and size scale of the native extracellular matrix. These fibrous scaffolds are also useful as cell culture substrates since the fibers can be used to direct cellular behavior, including stem cell differentiation (see extensive reviews by Mauck et al. and Sill et al. for more information). In this article, we describe the general process of electrospinning polymers and as an example, electrospin a reactive hyaluronic acid capable of crosslinking with light exposure (see Ifkovits et al. for a review on photocrosslinkable materials). We also introduce further processing capabilities such as photopatterning and multi-polymer scaffold formation. Photopatterning can be used to create scaffolds with channels and multi-scale porosity to increase cellular infiltration and tissue distribution. Multi-polymer scaffolds are useful to better tune the properties (mechanics and degradation) of a scaffold, including tailored porosity for cellular infiltration. Furthermore, these techniques can be extended to include a wide array of polymers and reactive macromers to create complex scaffolds that provide the cues necessary for the development of successful tissue engineered constructs.

The process of electrospinning polymers for tissue engineering and cell culture is addressed in this article. Specifically, the electrospinning of photoreactive macromers with additional processing capabilities of photopatterning and multi-polymer electrospinning is described.

静电纤维聚合物支架用于组织工程和细胞培养

As the field of tissue engineering evolves, there is a tremendous demand to produce more suitable materials and processing techniques in order to address ...