静电纺丝法制备组织工程纳/微米纤维支架

静电纺丝是一种简便易行的新型组织工程多孔支架制备方法,电纺支架具有独特的微观结构和适当的力学性能.由于具有与天然细胞外基质相近的纳米级结构,电纺支架能够仿生细胞外基质的结构特点,使之有望成为理想的组织工程支架.文中介绍了静电纺丝和同轴静电纺丝的基本原理和发展过程、电纺支架的加工方法和结构特点以及电纺纤维的定向收集技术,阐述了各种天然和合成聚合物纳/微米电纺支架在软骨、骨、血管、心脏、神经等组织工程领域的应用,并展望其应用前景.     

组织工程三维多孔支架制备技术的最新进展

理想的组织工程支架是由具有一定降解性能的高分子材料制成的,制备的支架除了要有一定的孔隙率和适于细胞生长的孔径外,还要有较高的机械性能和生物活性.为此介绍了用于组织工程中的可降解高分子材料,并详细阐述了最新的制备组织工程支架的方法:超临界CO2技术,计算机辅助成型技术,以及静电纺丝技术.     

静电纺丝技术研究进展及其应用

简述了静电纺丝技术的原理和静电纺丝工艺的主要影响因素;介绍了静电纺丝法在生物医用功能材料、过滤介质材料、增强复合材料、传感器、电子材料、新型特殊纤维等领域的应用;指出静电纺丝制备纳米纤维的研究方向。     

静电纺丝纳米纤维的制备与应用

静电纺丝技术是一种简单有效、廉价、无污染的制备纳米纤维的新方法,近年来在制备纳米纤维领域得到了广泛应用.通过静电纺丝法制备的纳米纤维具有长径比大、孔隙率高、比表面积大等优点,在过滤材料、生物医学、传感器、电子器件等领域都有着良好的应用前景.本文综述了静电纺丝制备纳米纤维的基本原理和最新发展,阐述了近几年来国内外静电纺丝纤维在过滤材料、生物医学、传感器、电子器件及其他一些特殊领域中的研究现状,并展望了静电纺丝纳米纤维的发展趋势和研究方向.     

纤维基组织工程心脏瓣膜支架研究进展

心脏瓣膜损坏或缺陷所导致的疾病已成为危害人类健康的主要疾病之一.由纤维材料成型技术制备的组织工程支架具有良好的可设计性和较好的力学和生物性能,逐渐成为组织工程心脏瓣膜支架的主要制备方法.全文重点介绍了纤维基组织工程心脏瓣膜支架的研究进展,对采用针织、非织造以及静电纺丝制备技术得到的微纳米纤维基支架的各自特点进行了对比分析,由此表明具有优良生物相容性和可控力学性能的三维多孔纳米纤维基支架将是组织工程心脏瓣膜支架的发展方向.     

熔体静电纺丝技术研究进展

熔体静电纺丝技术作为一种不使用溶剂的超细纤维绿色制备工艺，在高性能无纺布、生物医药和高效过滤等方面有着广泛的应用。本文简单回顾了熔体静电纺丝研究历史，阐述了熔体静电纺丝工艺特点，综述了近年来熔体静电纺丝工艺、材料、装置及应用新进展，介绍了笔者团队熔体微分静电纺丝技术，并在最后提出几点对未来熔体静电纺丝研究重点的看法。通过本文，以期增进对超细纤维绿色制造新理论、新方法和新装备的认识。     

透明质酸改性PHBV组织工程纳米纤维支架的研究

组织工程支架材料表面性质对细胞的黏附起着重要作用,进而影响细胞的增殖、分化等一系列生长过程.本研究采用天然生物大分子透明质酸(hyaluronic acid,HA)对聚(3-羟基丁酸酯-co-3-羟基戊酸酯)(Poly(3-hydroxybutyrate-co-3-hydroxyvalerate),PHBV)进行表面修饰以提高材料的表面生物活性.首先通过静电纺丝法制备PHBV纳米纤维支架,利用1,6-己二胺胺解在PHBV表面引入自由胺基,并以此为反应活性位点在水溶性的碳化二亚胺/N-羟基琥珀酰亚胺缩合剂体系中将透明质酸固定接枝在PHBV表面.SEM结果表明,静电纺丝制备的PHBV纳米纤维支架表面平滑程度高,纤维直径分布较均匀,且没有串珠;FTIR证明1,6-己二胺改性及透明质酸接枝改性PHBV纳米纤维支架材料均成功实现;茚三酮法表明PHBV表面胺基密度随胺解时间增加而增大,在胺解约50min时达到最大值;水接触角法表明固定接枝透明质酸后,表面亲水性明显改善;细胞实验表明透明质酸改性的PHBV纳米纤维支架可显著促进软骨细胞的体外增殖.综上所述,透明质酸改性的PHBV纳米纤维支架可望应用于软骨组织工程领域.     

纤维基支架在骨和软骨组织再生中的应用

组织工程对于骨和软骨组织缺损的修复具有广阔的发展前景。在组织工程三要素之一的支架中,纤维基支架由于具有较大的比表面积、相互连通的多孔结构以及与天然细胞外基质相似等优势,在骨和软骨修复中展现出巨大的应用潜力。纤维支架的成型通常基于静电纺丝法、热致相分离法、自组装肽法和溶剂热法,血管化和软骨再生是此类支架在临床应用上面临的主要挑战。通过仿生天然骨和软骨组织的复杂结构、综合多种技术手段在结构和功能上设计纤维基三维多孔支架将是改善骨和软骨组织工程支架修复效果的主要发展方向。     

熔体微分静电纺丝纳米纤维高效绿色制备技术

纳米纤维在生物医疗、高效过滤及生化防护等领域有着广泛的应用前景。静电纺丝被学术界及工业界认为是最具产业化制备纳米纤维的前景技术之一,其中熔体静电纺丝无需使用溶剂,相比溶液静电纺丝,避免了有毒溶剂残留、回收及处理等问题,是聚合物纳米纤维绿色制造的发展方向。然而,受到装备复杂、工艺滞后的影响,熔体静电纺丝始终未能突破纤维细化难、制备效率低的瓶颈。为此,团队创新提出了熔体微分静电纺丝新方法,经过十余年探索,围绕其工艺、装备、材料及应用等进行了系统的研究,率先实现了500 nm范围内熔体电纺纳米纤维的工业化制备,并建立了世界上第一套熔体微分静电纺丝纳米纤维工业化生产线。本文将从熔体微分静电纺丝的机理、关键技术、纳米纤维批量绿色制造及应用三个方面介绍熔体微分静电纺丝的研究成果及最新进展。     

静电纺丝实验教学课程的设计及探索

静电纺丝技术作为一种新兴的纳米纤维成型技术,从理论到实践都已日渐成熟。其作为唯一可以连续生产纳米纤维的技术已被广泛应用于生产生活中,例如过滤,传感器,药物释放,组织工程和电池电极材料等。将最新的静电纺丝技术引入实验教学中,不仅扩充和完善了实验教学体系,而且在实验教学过程中新兴前沿技术的引入可极大激发学生的学习兴趣和求知欲。     

Formation of drug-loaded electrospun twin fibers

Electrospinning is a well-known process for producing submicrometer fibers, which have wide applications in many fields, especially in tissue engineering scaffolds and drug-delivery systems. This paper presents the formation of drug-loaded electrospun twin fibers. The correlations between the twin fiber formation and the polymer materials or the loaded drugs were studied by using poly(l-lactide) and poly(l-lactide-co-glycolide) as electrospinning materials, and rifampin and paclitaxel as loaded drugs. Scanning electron microscopy showed that the formation of twin fibers is significantly affected by the loaded drug but not the polymer material. A possible reason for twin fiber formation was analyzed.     

Preparation of fiber-microsphere scaffolds for loading bioactive substances in gradient amounts

Gradient scaffolds are needed for interface tissue regeneration. In this study, a technique combining electrospinning and electrospraying was developed for preparing poly(L-lactide-co-glycolide) (PLGA) fiber-microsphere scaffolds for loading bioactive substances in gradient amounts. The gradient fiber-microsphere scaffolds contain two sheets of electrospun membranes and a sheet of microspheres loaded with bioactive substances in gradient amounts between the electrospun membranes. The morphologies of the gradient scaffolds were characterized and bovine serum albumin (BSA) was loaded as a model bioactive substance. The amount of BSA-loaded microspheres decreased gradually along the length of the gradient scaffold. The addition of poly (ethylene glycol) significantly improved the hydrophilicity of the gradient scaffold and the release behavior of BSA with respect to the gradient became apparent, with differences in the release amounts along the length of the gradient scaffold being observed. The biocompatibility of the gradient scaffold was verified using MC3T3-E1 pre-osteoblastic cells. The study demonstrated that the combination of electrospinning and electrospraying was a feasible method for the preparation of gradient scaffolds for potential applications in interface tissue engineering.     

Green Electrospun Silk Fibroin/Galactose Chitosan Composite Nanofibrous Scaffolds for Hepatic Tissue Engineering

The electrospun nanofibrous scaffolds made of proteins and polysaccharides were thought to be able to simulate the structure of natural extracellular matrix well.Silk fibroin(SF)and chitosan(CS)are probably the most widely used natural materials in biomedical fields including liver tissue engineering for their good properties and wide variety of sources.The asialoglycoprotein receptors of hepatocyte were reported to specifically recognize and interact with galactose.In this work,a green electrospun SF/galactosylated chitosan(GC)composite nanofibrous scaffold was fabricated and characterized.The data indicated that the addition of GC greatly influenced the spinning effect of SF aqueous solution,and the average diameter of the composite nanofibers was about 520nm.Moreover,the green electrospun SF/GC nanofibrous scaffolds were demonstrated significantly enhancing the adhesion and proliferation of hepatocyte(RH35)according to our data.The present study did a useful exploration on constructing scaffolds for liver regeneration by green electrospinning,and also laid a good foundation for the further applicative research of this green electrospun scaffolds in liver tissue engineering.     

静电纺丝参数对聚乳酸超细纤维支架形貌的影响

以聚乳酸为原料,采用静电纺丝技术制备纤维支架,研究了溶剂种类和工艺参数对纤维支架和纤维直径的影响规律.结果表明,采用四氢呋喃纯溶剂,所获纤维表面粗糙多孔,采用二氯甲烷可以获得表面光洁的纤维;随着纺丝液浓度的增加,电纺纤维直径增加,串珠形状由不规则形过渡至扁平形和球形,并且纤维直径显著增加;随着纺丝电压的升高,纤维直径呈下降趋势.     

Disc-Electrospun PCL Nanofiber Formed Micro-patterned Structure Scaffold

Disc-electrospinning using a disc as spinneret and a rotary drum as collector is a novel technology to prepare nanofiber which has been applied in tissue engineering scaffolds. In this study, nanofibrous mats with mlcro-patterned structure were fabricated via disc-electrospinning. Poly （ε-eaprolactone） （PCL） was dissolved in trifluoroethanol （TFE） at various concentrations （ 2 %-7 % ） （w/v） for electrospinning and the applied voltage ranged from 40 to 70 kV. Scanning electron microscopy （SEM） was employed to observe the morphology of the nanofibrous scaffolds. SEM images illustrated that the nanofibers with beads formed micro-patterned structure such as triangles and other polygons. The average diameter of nanofibers presented various size with the concentration increased from 2% to 7%. The beads on the nanofibers constructed the vertexes of the polygons, while nanofibers bridged between adjacent vertexes. The concentration of solution and applied voltage may be two dominant factors to influence the topological structure of the nanofibrons scaffolds. Cells cultured on the micro-patterned scaffold spread along the edges of the polygons. The scaffold with patterned structure may have a promising application in tissue engineering.     

Control of the morphology of micro/nanostructures of polycarbonate via electrospinning

Many of the applications proposed for bioassays, scaffolds for tissue engineering, filtrations, and supports for catalysts require polymeric membranes with large specific surface areas. Polycarbonate （PC） is a possible candidate for these applications because of its excellent mechanical performance and good biocompatibility. Electrospinning is a simple and effective method for large-scale fabrication of micro-/nanofibrous membranes with large specific surface areas. How to control the morphology of electrospun PC fibers, however, has not been systematically investigated. We describe the controllable fabrication of continuous and uniform PC fibers. We electrospin PC/chloroform solutions doped with different types of surfactants including anionic, zwitterionic, nonionic and cationic surfactants. Only cationic surfactants can lead to the successful fabrication of uniform PC fibers. After the analysis of the correlation between solution properties such as viscosity, surface tension, and conductivity and the morphology of electrospun fibers, we conclude that the addition of cationic surfactants such as cetane trimethyl ammonium bromide （CTAB） that leads to a decrease in viscosity is the main factor responsible for the formation of PC fibers. The demonstration of the fabrication of uniform PC fibers will lend experience to processing other polymers into fibers via electrospinning.     

骨组织工程聚左旋乳酸多孔框架快速成形研究

为制备用于骨组织工程的细胞载体框架结构 ,对快速成形技术制备聚左旋乳酸多孔框架结构的若干基础问题进行了研究。提出了聚左旋乳酸快速成形的精密挤出成形工艺 ,研究了此工艺制备多孔框架结构的设备与工艺过程 ,分析了制备的多孔框架结构应用于组织工程人工骨的可行性。制备的多孔框架结构具有合适的分子量、孔隙结构、孔隙率、机械强度和生物降解性能 ,可以用作骨组织工程的组织再生框架结构     

VE TPGS-Loaded Silk Fibroin/Hydroxybutyl Chitosan Nanofibrous Scaffolds for Skin Care Application

Vitamin E（ VE） is an ideal antioxidant and a stabilizing agent in biological membranes. In this study,silk fibroin（ SF） /hydroxybutyl chitosan（ HBC） nanofibrous scaffolds are loaded with VE tocopherol polyethylene glycol 1000 succinate（ VE TPGS） via electrospinning. SEM images show that the average nanofibrous diameter has no significant difference when the content of VE TPGS increases to 4. 0%（ SF / HBC）. However,the average nanofibrous diameter decreases largely to 200 nm when the VE TPGS content reaches 6. 0%. Furthermore,VE TPGS presents a sustained release behavior from the nanofibrous scaffolds. Cell viability studies of mouse skin fibroblasts（ L929） demonstrate that VE TPGS loaded SF / HBC nanofibrous scaffolds present good cellular compatibility.Moreover,the incorporation of VE TPGS could strengthen the ability of SF / HBC nanofibrous scaffolds on protecting the cells against oxidation stress using the Tertbutyl hydroperoxide（ t-BHP）-induced oxidative injury model. Therefore,VE TPGS-loaded SF /HBC nanofibrous scaffolds might be potential candidates for personal skin care,wound dressing and skin tissue engineering scaffolds.     

小直径血管支架的仿生构建及其种子细胞

静电纺丝仿生天然细胞外基质(ECM)结构,所制备的高度多孔、高比表面积的纳米级(50～500nm)纤维赋予了丰富的分子架构和生化信号,为种子细胞提供理想的生长微环境.不同组分、纤维尺寸及取向和种子细胞类型,可以裁剪获得不同生化和力学性能的电纺支架细胞复合物.总结了血管组织工程仿生ECM的设计与构建,并强调与支架复合的种子细胞在血管组织工程的作用.