电纺丝技术制备生物活性复合纤维支架及其体外降解性

背景:聚乳酸/羟基磷灰石类复合材料支架常用的制备方法主要有冷压法、粒子沥滤法、热致相分离法等,但是在增强材料界面的结合、调节材料的降解速率、改善材料的强度等方面仍不能满足要求。目的:制备左旋聚乳酸/羟基磷灰石复合纳米纤维支架。方法:采用静电纺丝法制备聚乳酸/羟基磷灰石复合纳米纤维支架。以扫面电镜对纤维的结构形态进行分析,并观察其在PBS中浸泡不同时间的体外降解过程。结果与结论:羟基磷灰石纳米粒子与聚乳酸/基体间存在化学键合,纳米粒子使纤维直径增大且表面粗糙程度增加,这种结构将有利于细胞在纤维膜上的伸展和和繁殖。羟基磷灰石的引入,抑制了聚乳酸降解过程中的自催化作用,减缓了聚乳酸的降解速度。说明电纺丝技术制备的聚乳酸/羟基磷灰石复合支架在组织工程支架材料方面具有潜在的应用前景。     

电纺丝技术制备生物活性复合纤维支架及其体外降解性

背景：聚乳酸/羟基磷灰石类复合材料支架常用的制备方法主要有冷压法、粒子沥滤法、热致相分离法等,但是在增强材料界面的结合、调节材料的降解速率、改善材料的强度等方面仍不能满足要求。目的：制备左旋聚乳酸/羟基磷灰石复合纳米纤维支架。方法：采用静电纺丝法制备聚乳酸/羟基磷灰石复合纳米纤维支架。以扫面电镜对纤维的结构形态进行分析,并观察其在PBS中浸泡不同时间的体外降解过程。结果与结论：羟基磷灰石纳米粒子与聚乳酸/基体间存在化学键合,纳米粒子使纤维直径增大且表面粗糙程度增加,这种结构将有利于细胞在纤维膜上的伸展和和繁殖。羟基磷灰石的引入,抑制了聚乳酸降解过程中的自催化作用,减缓了聚乳酸的降解速度。说明电纺丝技术制备的聚乳酸/羟基磷灰石复合支架在组织工程支架材料方面具有潜在的应用前景。     

气电纺纳米羟基磷灰石/聚羟基丁酸酯复合纤维支架对大鼠骨髓基质细胞成骨分化的影响

背景:利用静电纺丝技术制备的纤维支架材料具有类似于细胞外间质的形态和结构,且其独特的生产工艺可以很便捷地将功能性纳米颗粒复合入高分子纤维内,在制备组织工程支架方面具有独特的优势.目的:创新性地将物理共混法与气流-高压静电纺丝技术相结合,仿生构建纳米羟基磷灰石/聚羟基丁酸酯复合纳米纤维支架材料,评价其作为骨组织工程支架在体外的生物活性.设计、时间及地点:细胞学体外实验,于2008-03/2009-04在四川大学口腔疾病研究国家重点实验室完成.材料:按照预定参数进行气流-高压静电纺丝,分别制备气电纺纯聚羟基丁酸酯纤维支架及含质量分数为10%纳米羟基磷灰石的纳米羟基磷灰石,聚羟基丁酸酯复合纤维支架.方法:将大鼠骨髓基质细胞接种于纳米羟基磷灰石/聚羟基丁酸酯纳米纤维支架后进行体外培养(实验组),以接种于气电纺纯聚羟基丁酸酯纳米纤维支架为对照组,接种于细胞培养板为空白对照组.主要观察指标:通过RT-PCR检测连续培养14 d后细胞成骨分化标志物碱性磷酸酶、I型胶原和骨钙素的mRNA表达.结果:各组均能检测到3种成骨标志物碱性磷酸酶、I型胶原和骨钙素的mRNA表达.通过Quantity One软件分析计算目的条带吸光度值与内参β-actin条带吸光度值的比值,可以发现3种目的基因在实验组具有最高表达水平,其次为对照组,空白对照组的表达明显最弱.结论:气电纺纳米羟基磷灰石,聚羟基丁酸酯复合纤维支架可促进大鼠骨髓基质细胞成骨分化,证实其在体外具有优良的生物活性.     

纳米羟基磷灰石/聚己内酯复合大鼠骨髓间充质干细胞的生物相容性

背景:纳米羟基磷灰石/聚己内酯是一种具有优良生物相容性和生物活性的典型生物复合材料.目的:分析纳米羟基磷灰石/聚己内酯电纺薄膜作为组织工程骨支架的可行性.方法:采用静电纺丝技术制备纳米羟基磷灰石/聚己内酯电纺薄膜,将其与第3代 SD 大鼠骨髓间充质干细胞复合培养,在地塞米松、β-磷酸甘油钠、维生素C成骨诱导剂诱导下,诱导骨髓间充质干细胞向成骨细胞转化.结果与结论:纳米羟基磷灰石/聚己内酯支架具有合适的微孔结构,且孔道相互贯通.①倒置显微镜观察:复合培养7 d后细胞大部分为梭形,细胞开始分裂;14 d后,细胞生长比较旺盛,数量明显增多,细胞分泌基质并黏附于支架上.②扫描电镜观察:复合培养7 d后大量细胞位于支架孔隙内生长,增殖良好,细胞大多呈梭形,双极突起,形态较佳,呈立体状生长,并分泌基质,有纤维连接蛋白生成.表明纳米羟基磷灰石/聚己内酯支架具有良好的生物相容性,是骨组织工程的良好载体.     

骨修复用纳米羟基磷灰石/聚酰胺66的体内外生物相容性(英文)

背景:采用基于纳米羟基磷灰石溶胶新方法制备纳米羟基磷灰石/聚酰胺66复合材料,该材料提高了纳米羟基磷灰石在聚酰胺66基体中的均匀分布和二者的有效键合,进而有利于改善材料的生物性能,有望成为新型骨修复材料.目的:评价纳米羟基磷灰石/聚酰胺66复合材料体内外生物相容性.方法:①将原代培养的成骨细胞与纳米羟基磷灰石/聚酰胺66及聚酰胺66材料复合培养,使用倒置相差显微镜和场发射扫描电子显微镜观察材料周围及表面的细胞形态.②将纳米羟基磷灰石/聚酰胺66复合材料植入兔右侧胫骨,将聚酰胺66作为对照组材料植入兔左侧胫骨.在术后2,8周,取材料周围骨组织进行病理组织切片观察.结果与结论:①纳米羟基磷灰石/聚酰胺66和聚酰胺66未表现出明显的细胞毒性,纳米羟基磷灰石,聚酰胺66材料周围细胞形态好于聚酰胺66,且纳米羟基磷灰石僳酰胺66表面细胞数量多于聚酰胺66,在复合培养的第3天差异尤其显著(P<0.01).②在植入早期,与纳米羟基磷灰石僳酰胺66相接的骨组织成骨细胞活跃且该组材料周围的骨形成过程较对照组更快.结果说明纳米羟基磷灰石/聚酰胺66复合材料较聚酰胺66有更好的生物相容性.     

纳米羟基磷灰石/胶原蛋白/丝素蛋白复合骨组织工程支架材料的生物相容性

背景:通过将两种及两种以上材料共混制备复合支架材料可以弥补各自的不足,利用各种材料的互补特性来满足组织工程对支架的要求。目的:制备纳米羟基磷灰石/胶原蛋白/丝素蛋白复合三维支架材料,并研究其细胞相容性。方法:将纳米羟基磷灰石、胶原蛋白与丝素蛋白分别按质量比为1∶1∶5、1∶2∶5、1∶3∶5的比例混合,制备纳米羟基磷灰石/胶原蛋白/丝素蛋白复合材料,测试其孔隙率、孔径大小、吸水膨胀率及压缩力学性能。将表征结果良好的质量比为1∶2∶5的纳米羟基磷灰石/胶原蛋白/丝素蛋白复合材料与MC3T3-E1细胞体外复合培养,MTT法检测复合培养2,4,6,8,12 d后的细胞活性。结果与结论:羟基磷灰石/胶原蛋白/丝素蛋白按质量1∶2∶5的比例混合更符合要求:孔径98-260μm,孔隙率为(96.72±2.78)%,吸水膨胀率为(549.37±35.29)%,生物力学试验机测定其力学性能稳定、压缩应变及弹性模量等指标适宜骨组织工程研究应用。MC3T3-E1细胞在纳米羟基磷灰石/胶原蛋白/丝素蛋白复合三维支架上生长增殖良好,表明纳米羟基磷灰石/胶原/丝素复合三维支架具有良好的细胞相容性。     

不同组分电纺丝素蛋白/聚己内酯超细纤维膜与小鼠成纤维细胞的相容性

背景:近年来,静电纺丝法已被认为是一种制各纳米至亚微米级纤维组织工程支架的简便方法.目的:对3种由静电纺丝法制备的纤维膜进行生物学评价.设计、时间及地点:观察性实验,于2009 01/04在杭州师范大学临床医学院完成.材料:电纺丝素蛋白/聚己内酯超细纤维膜(SF70/PCL30,SF50/PCL50)以及丝素蛋白/聚己内酯/纳米羟基磷灰石超细纤维膜(SF50/PCL50-nHA,其中纳米羟基磷灰石含量为30%)由浙江理工大学省部共建"先进纺织材料与制备技术教育部重点实验室"制备.方法:将L929细胞以5.5×108L-1浓度接种在3种电纺超细纤维膜上进行培养.在1,3,5 h和1,4,7d时用MTT法测定细胞黏附和增殖情况,在1 d和7 d时扫描电镜观察细胞的形态.主要观察指标:L929细胞在电纺SF70/PCL30,SF50/PCL50,SF50/PCL50-nHA超细纤维膜上的黏附和增殖情况;L929细胞的形态特征.结果:相比于没有加入纳米羟基磷灰石的电纺纤维膜,电纺SF50/PCL50-nHA 超细纤维膜会较好地提高细胞在其上的黏附和增殖能力.扫描电镜观察也表明,L929细胞可以在电纺SF50/PCL5-nHA 超细纤维膜上很好地呈梭形生长,并且在其表面可以观察到丰富的绒毛和伪足,伪足与材料紧密相联.结论:3种电纺超细纤维膜特别是电纺SF50/PCL50-nHA 超细纤维膜可以很好地应用于组织再生.     

胶原-纳米羟基磷灰石复合支架的细胞相容性

背景:观察成骨细胞在生物材料上的形态、增殖和分化等项目,可评估生物支架材料的生物相容性。目的:观察复合支架材料纳米羟基磷灰石/胶原对成骨细胞增殖、分化的影响。方法:取新生24h内Wistar大鼠的颅盖骨,采用改良胶原酶消化法进行成骨细胞原代培养,取第3代细胞与纳米羟基磷灰石/胶原支架或普通羟基磷灰石材料体外复合培养。培养3,6,9d后,观察材料周边的细胞形态及支架材料对细胞分化、增殖的影响。结果与结论:纳米羟基磷灰石/胶原材料较普通的羟基磷灰石材料更有利于成骨细胞的黏附、生长、分化、增殖,证实其生物相容性更好,有望成为一种新型的骨组织工程支架材料。     

聚左旋乳酸/壳聚糖电纺丝纳米纤维支架与兔内皮祖细胞的生物相容性

背景：电纺丝技术能够使许多高分子材料制备出与细胞外基质相似的三维纳米纤维支架。聚乳酸/壳聚糖纳米纤维复合支架材料能够克服材料的不足,提高组织工程支架生物相容性。目的：评价聚左旋乳酸/壳聚糖电纺丝纳米纤维支架与兔内皮祖细胞的生物相容性。方法：电纺丝技术制备聚左旋乳酸,壳聚糖,聚左旋乳酸/壳聚糖的纳米纤维支架,扫描电镜观察其形貌结构。纳米纤维支架与内皮祖细胞进行复合培养后,观察细胞在不同材料上的黏附率、一氧化氮分泌,生长特征和在聚左旋乳酸/壳聚糖纳米纤维支架上的细胞表型特征。结果与结论：聚左旋乳酸/壳聚糖纳米纤维支架比聚左旋乳酸、壳聚糖具有更合适的纤维直径,具有与细胞外基质相似的纳米纤维三维多孔结构。聚左旋乳酸/壳聚糖纳米纤维支架能够促进内皮祖细胞黏附率和细胞的一氧化氮分泌（P〈0.05,P〈0.01）。内皮祖细胞能够在聚左旋乳酸/壳聚糖复合材料膜上融合成片,保持了细胞的完整形态和分化功能,显示了内皮细胞特异性的vWF表型。提示聚左旋乳酸/壳聚糖电纺丝纳米纤维支架与兔内皮祖细胞具有良好的生物相容性。     

骨组织工程纳米复合支架及其生物学评价

目的:综述骨组织工程常用支架材料的种类及其性能,同时,简介一种新型的,可降解的,具有三维空间网络结构的纳米支架材料——细菌纤维素/羟基磷灰石复合材料,并探讨纳米生物材料的安全性评价.资料来源:检索人为第一作者,检索文献时限为1979-01/2009-06,检索数据库为PubMed数据库(http://www.ncbi.nlm.nih.gov/PubMed)及CNKI数据库(www.cnki.net/index.htm).中文检索词"骨组织工程,细菌纤维素,安全性评价";英文检索词为"bone tissue engineering,Bacterial cellulose,safety evaluation".资料选择:①文章所述内容与骨组织工程密切相关.②有关于纳米材料安全性评价的文章.结局评价指标:骨组织工程材料的种类及性能,纳米材料的安全性.结果:常用的3种支架材料有天然生物材料,人工合成高分子生物材料及陶瓷材料.单一材料难以满足组织工程所需的机械强度和生物相容性,而生理状态的磷灰石是纳米级,纳米级复合材料更符合仿生的原则.细菌纤维素与具有极好生物活性、骨传导作用和骨结合能力的纳米羟基磷灰石复合制成纤维状复合支架材料,不仅具有足够的强度,还具有骨传导功能,以满足骨细胞在支架上的黏附和繁殖,成为一种很有前途的骨组织工程纳米支架材料.对生物材料生物相容性的研究与评价,不仅要从整体水平去观察材料对人体各系统的影响,从细胞水平去观察材料对细胞的数量、形态及分化的影响,还要深入到分子水平去观察材料对细胞DNA、mRNA以及蛋白表达水平的影响.结论:由于细菌纤维素,羟基磷灰石复合支架材料结合细菌纤维素和羟基磷灰石两种材料的优点,其复合产物的性能将优于传统的骨组织工程产品.对其完成一系列生物相容性评价后,新一代骨组织工程三维纳米纤维仿生支架材料便可安全的投入到临床应用.     

聚酯酰胺静电纺纳米纤维膜的制备及其生物相容性

采用静电纺技术制备聚酯酰胺纳米纤维膜,用扫描电镜观察纳米纤维的表面形貌,发现随着纺丝液质量浓度的增加,纤维的直径由10%时的180 nm递增到20%时的350 nm;用红外光谱表征聚酯酰胺的化学结构,结果表明化学结构在纺丝前后没有发生明显变化;X射线衍射法测试表明聚酯酰胺在经过溶剂处理和纺丝后,结晶度下降;差示扫描量热法表征了热力学特性,发现聚酯酰胺经过溶剂处理和纺丝后,结晶度下降;力学性能测试表明平均厚度为(0.50±0.05)mm的聚酯酰胺纳米纤维膜的平均断裂强度和平均断裂伸长率分别达到(1.00±0.18)MPa和(18.20±2.86)%;MTT结果表明内皮细胞在聚酯酰胺纳米纤维膜上增殖活跃,内皮细胞在纤维表面黏附并显示出良好的生长形态.     

Electrospun fibers and their application in drug controlled release,biological dressings,tissue repair,and enzyme immobilization

Electrospinning is a method of preparing microfibers or nanofibers by using an electrostatic force to stretch the electrospinning fluid. Electrospinning has gained considerable attention in many fields due to its ability to produce continuous fibers from a variety of polymers and composites in a simple way. Electrospun nanofibers have many merits such as diverse chemical composition, easily adjustable structure, adjustable diameter, high surface area, high porosity, and good pore connectivity, which give them broad application prospects in the biomedical field. This review systematically introduced the factors influencing electrospinning, the types of electrospun fibers, the types of electrospinning, and the detailed applications of electrospun fibers in controlled drug release, biological dressings, tissue repair and enzyme immobilization fields. The latest progress of using electrospun fibers in these fields was summarized, and the main challenges to be solved in electrospinning technology were put forward.

Electrospun fibers have gained considerable attention in drug controlled release, biological dressings, tissue repair and enzyme immobilization fields.     

Electrospinning of pyrazole-isothiazole derivatives: nanofibers from small molecules

We investigate the electrospinning of small molecules, specifically designed peptide derivatives of the pyrazole-isothiazole scaffold. Such non-natural peptides enhance the spectrum of fundamental materials used for electrospinning. Unlike standard electrospun materials, our peptides are not polymeric, but able to aggregate in solution and especially during processing. They contain donor/acceptor groups that can form hydrogen bonds, and groups that are able to generate π-stacking interactions, which are known as important requirements for assembly processes. The pyrazole-isothiazole derivatives were synthesized by means of a 1,3-dipolar cycloaddition reaction, which is completely regioselective, affording only one isomer. We demonstrate that our compounds can be electrospun from fluoroalcohol solution into solid, quasi-endless micro- and nanofibers. The electrospinnability varies substantially, depending on the amino acids linked to the scaffold. Some compounds provide only short fibers, while Fmoc-glycyl-(N-benzyl)-pyrazole-isothiazole-tert-butyl carboxylate-1,1-dioxide forms continuous, homogenous, and bead-free fibers (droplet-like beads are a common problem in electrospinning). We analyzed the compounds and the fibers with various spectroscopic techniques (MS, IR and Raman). Electrospinning does not change chemical composition and configuration, suggesting the monomeric form of the compounds even in the fibers. Interestingly, we found that the stereochemistry of the scaffold can affect the ability of the peptide to be electrospun.

Pyrazole-isothiazole monomers are electrospun from solution into solid, quasi-endless micro- and nanofibers.     

Fibrous biodegradable l‐alanine‐based scaffolds for vascular tissue engineering

In vascular tissue engineering, three‐dimensional (3D) biodegradable scaffolds play an important role in guiding seeded cells to produce matrix components by providing both mechanical and biological cues. The objective of this work was to fabricate fibrous biodegradable scaffolds from novel poly(ester amide)s (PEAs) derived from l ‐alanine by electrospinning, and to study the degradation profiles and its suitability for vascular tissue‐engineering applications. In view of this, l ‐alanine‐derived PEAs (dissolved in chloroform) were electrospun together with 18–30% w/w polycaprolactone (PCL) to improve spinnability. A minimum of 18% was required to effectively electrospin the solution while the upper value was set in order to limit the influence of PCL on the electrospun PEA fibres. Electrospun fibre mats with average fibre diameters of ~0.4 µm were obtained. Both fibre diameter and porosity increased with increasing PEA content and solution concentration. The degradation of a PEA fibre mat over a period of 28 days indicated that mass loss kinetics was linear, and no change in molecular weight was found, suggesting a surface erosion mechanism. Human coronary artery smooth muscle cells (HCASMCs) cultured for 7 days on the fibre mats showed significantly higher viability (p < 0.0001), suggesting that PEA scaffolds provided a better microenvironment for seeded cells compared with control PCL fibre mats of similar fibre diameter and porosity. Furthermore, elastin expression on the PEA fibre mats was significantly higher than the pure PEA discs and pure PCL fibre mat controls (p < 0.0001). These novel biodegradable PEA fibrous scaffolds could be strong candidates for vascular tissue‐engineering applications. Copyright © 2012 John Wiley & Sons, Ltd.     

静电纺丝聚膦腈/明胶复合纤维支架的生物矿化行为

背景:虽然静电纺丝高分子纤维的生物矿化研究文章已不少见,但国内外尚无关于静电纺丝聚膦腈及其与明胶复合纤维的生物矿化研究报道.目的:考察聚膦腈/明胶复合纤维支架作为骨组织工程支架的可行性.方法:静电纺丝法构建生物可降解聚膦腈/明胶复合纤维支架,采用5 倍模拟体液,并结合扫描电镜、X 射线能谱、X 射线光电子能谱、傅里叶变换红外光谱等手段,观察其生物矿化行为.结果与结论:与纯明胶的纤维膜相比,聚(丙氨酸乙酯-甘氨酸乙酯)膦腈(PAGP)和明胶混合溶液静电纺丝得到的复合纤维膜,经交联处理后仍能够保持良好的纤维形貌和多孔结构.在采用CO2 平衡的改进5 倍模拟体液中,纯PAGP和PAGP/明胶纤维表面沉积的矿物质都经历了片状二水合磷酸一氢钙前驱体的生成及其向羟基磷灰石转化的过程,但后者由于明胶成分的存在,整个过程发生发展的速度要明显快于前者.而对于纯明胶纤维,其在改进5 倍模拟体液中浸泡24 h 后,所生成矿物质仍主要为羟基磷灰石的前驱体二水合磷酸一氢钙.说明复合纤维中,疏水性PAGP的引入不仅有利于纤维形貌的保持,还能抑制明胶的溶出,使PAGP /明胶复合纤维的矿化性能明显改善.     

Nanofibers with diameter below one nanometer from electrospinning

Sub-nanometer materials have received wide attention due to their unique properties in recent years. Most studies focus on the preparation and properties investigation of the inorganic sub-nanometer materials, while there are few reports on organic especially polymeric sub-nanometer materials such as sub-nanometer fiber due to the obstacles with respect to fabricating such small nanofibers. In this work we prepare PAA nanofibers with diameters ranging from hundreds of nanometers down to sub-nanometer via electrospinning from a polyamic acid (PAA) with ultrahigh molecular weight. The morphologies and size of the electrospun ultrathin nanofibers are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). AFM images combined with theoretic calculations show that sub-nanometer fiber of approximate 0.17–0.63 nm only containing one molecular chain was generated via electrospinning from ultra-dilute PAA solutions for the first time. These quite small sub-nanometer fibers would open a new area of electrospinning and provide further explorations on the production and application of electrospun sub-nanometer fibers with single molecular chains.

Super-fine nanofibers with diameter below 1 nanometer are prepared by electrospinning from ultra-dilute solutions.     

静电纺丝聚膦腈/明胶复合纤维支架的生物矿化行为

背景：虽然静电纺丝高分子纤维的生物矿化研究文章已不少见,但国内外尚无关于静电纺丝聚膦腈及其与明胶复合纤维的生物矿化研究报道。目的：考察聚膦腈/明胶复合纤维支架作为骨组织工程支架的可行性。方法：静电纺丝法构建生物可降解聚膦腈/明胶复合纤维支架,采用5倍模拟体液,并结合扫描电镜、X射线能谱、X射线光电子能谱、傅里叶变换红外光谱等手段,观察其生物矿化行为。结果与结论：与纯明胶的纤维膜相比,聚（丙氨酸乙酯-甘氨酸乙酯）膦腈（PAGP）和明胶混合溶液静电纺丝得到的复合纤维膜,经交联处理后仍能够保持良好的纤维形貌和多孔结构。在采用CO2平衡的改进5倍模拟体液中,纯PAGP和PAGP/明胶纤维表面沉积的矿物质都经历了片状二水合磷酸一氢钙前驱体的生成及其向羟基磷灰石转化的过程,但后者由于明胶成分的存在,整个过程发生发展的速度要明显快于前者。而对于纯明胶纤维,其在改进5倍模拟体液中浸泡24h后,所生成矿物质仍主要为羟基磷灰石的前驱体二水合磷酸一氢钙。说明复合纤维中,疏水性PAGP的引入不仅有利于纤维形貌的保持,还能抑制明胶的溶出,使PAGP/明胶复合纤维的矿化性能明显改善。     

Controlled three-dimensional polystyrene micro- and nano-structures fabricated by three-dimensional electrospinning

The combination of electrospinning with extrusion based 3D printing technology opens new pathways for micro- and nanofabrication, which can be applied in a wide range of applications. This simple and inexpensive method has been proven to fabricate 3D fibrous polystyrene structures with controlled morphology and micro- to nano-scale fibers diameter. The controllable movement of the nozzle allows precise positioning of the deposition area of the fibers during electrospinning. A programmed circular nozzle pattern results in the formation of controllable 3D polystyrene designed shapes with fiber diameters down to 550 nm. The assembly of the fibrous structures starts instantaneously, and a 4 cm tall and 6 cm wide sample can be produced within a 10 minutes electrospinning process. The product exhibits high stability at ambient conditions. The shape, size, and thickness of fibrous polystyrene structures can be easily controlled by tuning the process parameters. It is assumed that the build-up of 3D fibrous polystyrene structures strongly depends on charge induction and polarization of the electrospun fibers.

The combination of electrospinning and extrusion based 3D printing opens new pathways for micro- and nanofabrication in a wide range of applications. The fast production of a highly stable self-standing polystyrene 3D structure is demonstrated.     

静电纺丝纳米纤维组织工程支架的研究进展

背景：静电纺丝纳米纤维具有促进细胞生长的作用。目的：描述静电纺纳米支架对细胞生长的促进作用以及静电纺纳米支架孔径大小、机械强度缺陷改进的研究进展。方法：检索数据库为CNKI数字图书馆全文、PubMed数据库2001至2011年有关静电纺丝和组织工程支架的文献。检索关键词为“组织工程,静电纺丝,支架;electrospinning,tissue engineering scaffolds,nanofiber”。结果与结论：静电纺丝纳米纤维直径、孔径大小及纤维表面对细胞生长行为有重要影响,小孔径静电纺丝纳米纤维支架不利于细胞浸润生长,且用单一电纺技术制备得到的纳米纤维支架机械性能较差,如何增加静电纺丝纳米纤维支架孔径大小以提高细胞的浸润以及提高其机械性能强度,是目前应用研究应解决的问题。     

Bioactive bacterial cellulose sulfate electrospun nanofibers for tissue engineering applications

Cellulosic materials have been of tremendous importance to mankind since its discovery due to its superior properties and its abundance in nature. Recently, an increase in demand for alternate green materials has rekindled the interest for cellulosic materials. Here, bacterial cellulose has been functionalized with sulfate groups through acetosulfation to gain solubility in aqueous media, which provides access to several applications. The cell viability, antioxidant, and hemocompatibility assays have verified the biocompatible and antioxidant characteristics of bacterial cellulose sulfate (BCS) in both in vitro and ex vivo conditions. Further, novel BCS/polyvinyl alcohol nanofibers were fabricated by simple electrospinning route to engineer ultrafine nanoscale fibers. The biological evaluation of BCS/polyvinyl alcohol nanofiber scaffolds was done using L929 mouse fibroblast cells, which confirmed that these nanofibers are excellent matrices for cell adhesion and proliferation.