牛血清白蛋白改性壳聚糖纤维及其细胞亲和性研究

采用牛血清白蛋白对壳聚糖纤维进行化学改性，通过扫描电镜和含水量测定对改性的牛血清白蛋白-壳聚糖纤维进行表征．并对改性材料进行细胞相容性和细胞亲和性测定与评价．结果表明：牛血清白蛋白-壳聚糖纤维表面有明显附着物，纤维略微变粗；含水量增加到93．49％(质量分数)；细胞在改性克聚糖纤维上的形态无异常，粘附、生长、增殖情况良好；细胞毒性试验结果呈阴性．该改性壳聚糖纤维具有良好的生物学特性，能够应用于器官组织工程及生物医药领域．     

Compatibility of Chitosan-Gelatin Films with Adipose Tissue Derived Stromal Cells

Introduction Chitosan, the partially N-deacetylated form of chitin, is the second most abundant biomaterial after cellulose. Due to its biocompatibility, biodegradability, and bio- activity, chitosan and its derivant complexes have been studied in various…     

丙烯酸改性黏胶纤维及其吸水性研究

为提高黏胶纤维的吸水性,以硝酸铈铵(CAN)硝酸溶液为引发剂、丙烯酸(AA)为亲水单体、去离子水为溶剂,采用自由基聚合法进行黏胶纤维的接枝共聚反应。利用红外光谱仪(FT-IR)、X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)和X射线衍射仪(XRD)等对接枝黏胶纤维的结构进行研究,同时探讨了接枝共聚反应条件对改性黏胶纤维接枝率和吸水性能的影响。结果表明,黏胶纤维表面成功接枝上聚丙烯酸,且当硝酸铈铵、硝酸、丙烯酸的质量分数分别为10%、1.0%、2.0%,反应温度为60℃时,改性黏胶纤维的接枝率和吸水倍率达到最大值。     

Fiber-Based Chitosan Tubular Scaffolds for Soft Tissue Engineering： Fabrication and in Vitro Evaluation

Porous, two-ply tubular chitosan conduits for guided tissue regeneration were fabricated by combining the textile technique （inner layer） with the thermally induced phase separation process （outer layer）. A hollow chitosan tube was prepared using an industrial warp knitting process with chitosan yarns. Then, an appropriate diameter mandrel was inserted into the pre-fabricated tube. The tube and the mandrel were dipped into the chitosan solution together, taken out, and freeze-dried. After being neutralized in alkaline solution and dried at room temperature, the mandrel was removed to create the chitosan tubular scaffold. Scanning electron micrographs show that the resulting tubes have a biphasic wall structure, with a fibrous inner layer and a semipermeable outer layer. The swelling properties and the mechanical strength before and after in vitro degradation were investigated. The biocompatibility of the scaffolds was also investigated by co-culturing neuroblastoma cells （N2A, mouse） with the scaffolds. The results suggest that these chitosan tubular scaffolds are useful for the regeneration of tissues requiring a tubular scaffold.     

新型明胶纳米纤维毡的制备及其细胞培养

以水为溶剂通过静电纺丝法制备出了新型明胶纳米纤维。结果表明，当明胶的质量分数为33%和体系温度为40℃时，所得明胶纳米纤维毡具有均匀多孔的微观形貌，纤维直径分布在120～210nm。用质量分数为1.5%的1-(3-二甲氨基丙基)-3-乙基碳二亚胺（EDC）/N-羟基琥珀酰亚胺（NHS）的乙醇/水溶液对纤维毡进行交联，所得明胶纳米纤维毡中纤维的形态得到较好的保持，且其焓值降低，耐热性和力学性能均有所提高。将制备的明胶纳米纤维毡进行牙周基质细胞（PDLCs）培养实验，初步的结果表明PDLCs能够在该纳米纤维毡上粘附、伸展和繁殖。     

Incorporation of hydroxyapatite in crosslinked gelatin/chitosan/poly(vinyl alcohol) hybrids utilizing as reinforced composite sponges,and their water absorption ability

The crosslinked gelatin/chitosan/poly(vinyl alcohol)/hydroxyapatite (GEL/CTS/PVA/HAp, GCPH) sponges were fabricated by a freeze-drying method to yield the reinforced composite sponges with proper features. The porosity value and pore size of the crosslinked GCPH sponges reached ∼80% and 50–100 ​μm, respectively, which can be an appropriate range to allow cells to migrate into the reinforced composite sponges in the tissue engineering technology. Besides, the proper bonding presence between HAp particles and the crosslinked polymeric matrix or the crosslinked network formation between the polymers were also proved through fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermal gravimetric (TG/DTG) analysis. Owing to incorporation of HAp particles and good distribution of HAp particles inside the crosslinked polymeric matrix, their mechanical properties were improved through the determination of compression tests. Concomitantly, their water absorption ability reached effectively in both the distilled water and NaCl solution, and their recovery also maintained well for 10 absorbing–squeezing cycles to be considered as an effective reusability for the crosslinked sponge system. Thereby, the crosslinked GCPH sponge prepared in the present study can become a potential candidate to apply especially in the biomedical/medical applications and tissue engineering technology.     

Fabrication and Characterization of Chitosan Nerve Conduits with Microtubular Architectures

Porous multi-channel chitosan conduits were fabricated using a novel phase-separation technique with an axial temperature gradient. First, porous chitosan tubes were made with a mold that was composed of two concentric polytetrafiuoroethylene tubes. Then 1%-3% （w/v） chitosan solution was injected into the chitosan tube while the two ends of the tube were closed with steel rods. Then the outside of the tube was wrapped with a layer of thermal insulating material to reduce the heat transfer through the outside, and the tubes were placed in a freezer. The resulting phase separation then occurred in the presence of an axial temperature gradient. The porosity, microtubule diameter, and orientation were controlled by adjusting the polymer concentration and temperature gradient. After the preparation course, no poisonous substances remained on the conduits. The mechanical properties, swelling, and biodegradability of the chitosan conduits were investigated, and a scanning electron microscope was used to observe the tubular morphology and growth of neuroblastoma cells （N2A, mouse） in the conduits. The results demonstrate that the multi-channel chitosan conduits have suitable mechanical strength, swelling, degradation properties, and nerve cell affinity, so they hold promise for use as neural tissue engineering scaffolds.     

Surface Graft Polymerization of PET and PE Fibers by UV Irradiation and Their Characteristics

Polyethylene terephthalate(PET)and polyethylene(PE)fibers were surface photo-grafted with acrylic acid(AA)by using UV irradiation photochemical initiationduring a continuous winding process within 1-2 min-utes.The grafted fibers were characterized by measure-ments of dye uptaking,moisture regain,pull-out forcesof monofilament from cured matrix,as well as by analy-sis of ESCA and ATR-FTIR spectra.All these resultsconfirm that the surface behavior of the UV-irradiationgrafted fibers was greatly improved.It was also provedthat the original excellent mechanical properties of the fi-bers were well-retained after the surface grafting treat-ment.     

Preparation and mineralization of PLGA/Gt electrospun fiber mats

Poly(lactic-co-glycolic acid)(PLGA)/gelatin(Gt) ultrafine composite fibers were fabricated via electro-spinning.The effect of gelatin on the morphology and tensile property of the electrospun fiber mats was investigated.Mineralization was carried out in 10×simulated body fluid(10SBF).The deposited calcium phosphate(CaP) was identified by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),X-ray diffraction(XRD) and Fourier transform infrared spectroscopy(FTIR).Results indicated that the av...     

一种新型两亲性壳聚糖衍生物的合成及性质的研究

首次合成了一种新型非离子型两亲性壳聚糖衍生物(2-羟基-3-丁氧基)丙基-丁二酰化壳聚糖(HBP-SCCHS)。用红外光谱和元素分析等手段对产物结构进行了表征，证明在壳聚糖分子上已成功地引入了疏水和亲水基团。研究表明，该新型壳聚糖衍生物具有良好的表面活性、泡沫性和乳化性，可以作为高分子表面活性剂使用。     

Fabrication and characterization of electrospun poly-L-lactide/gelatin graded tubular scaffolds: Toward a new design for performance enhancement in vascular tissue engineering

In this study, a new design of graded tubular scaffolds have been developed for the performance enhancement in vascular tissue engineering. The graded poly-L-lactide (PLLA) and gelatin fibrous scaffolds produced by electrospining were then characterized. The morphology, degradability, porosity, pore size and mechanical properties of four tubular scaffolds (graded PLLA/gelatin, layered PLLA/gelatin, PLLA and gelatin scaffolds) have been investigated. The tensile tests demonstrated that the mechanical strength and also the estimated burst pressure of the graded scaffolds were significantly increased in comparison with the layered and gelatin scaffolds. This new design, resulting in an increase in the mechanical properties, suggested the widespread use of these scaffolds in vascular tissue engineering in order to prepare more strengthened vessels.     

Chemical Modification of Silk Fibers with Ethylene Glycol Dimethacrylate

Silk fibers have been grafted with ethylene glycol dimethacrylate (EGDMA) and characteristics of the grafted silk fibers were analyzed in relation to the graft yield on the basis of the tensile properties, dyeing behaviour, durability during laundering and solubility of the specimen in NaOH solution. The amount of the acid dye absorbed by the fibers decreased with increasing graft yield, while the value of rating for washing fastness on silk fibers was almost unchanged by the graft treatment The breaking loads of the fiber were almost unchanged whereas rigidity of the fibers increased after graft treatment. Graft treatment enhanced silk fiber durability during laundering and in NaOH solution.     

Immobilization of biomacromolecules on poly-L-lactide surface via a layer-by-layer method for the improving of its cytocompatibility to bone marrow stromal cells

Hyaluronic acid （HA） and chitosan （CS） were immobilized on the surface of poly-L-lactide （PLLA） by the following procedure： Firstly, PLLA was aminolyzed with 1, 6-hexanediamine, and part of the PLLA surface ester groups were converted to free amino groups. Then negatively charged hyaluronic acid and positively charged chitosan were deposited onto the surface of aminolyzed PLLA film in a layer-by-layer assembly manner. The effect of the layer-by- layer deposition was evaluated by ATRoFTIR spectroscopy, Raman spectroscopy and static contact angle measurements. The cytocompatibility of PLLA sample to bone marrow stromal cells （BMSCs） was improved after modification with chitosan and HA. The cell attachment, activity, and proliferation on CS/HA modified PLLA films were enhanced comparing with the control. The cells cultured on the modified PLLA samples excreted abundant cytoplasm and can differentiate to vascular smooth muscle （SM）-like （SM-like） cells. A macroporous three-dimensional PLLA scaffold was prepared by integrating both the technique of freeze-drying and particle leaching. Layer-by-layer modification by HA/CS and cell culture was also applied on this scaffold. The scaffold cultured with BMSCs for 2 weeks has been tested successfully in vivo as a patch for repairing the artificial incision on canine pulmonary artery.     

Structures of Silk Fibers Grafted with Hexafluorobutyl Methacrylate

The relationship between the graft yield and the effect of hexafiuorobutyl methacrylate graft treatment on the structural changes of the silk fibers was studied on the basis of the results of scanning electron micrograph photographs （SEM）, infrared spectroscopy （IR）, Raman spectrum, wide-angle X-ray diffraction patterns （WAXD）, nuclear magnetic resonance（NMR） and amion acid analysis. The results showed that the crystalline regions of grafted fibers were hardly affected and the fiber fission occurred on the cross sections of grafted fibers. The surface of fibers was covered with a high polymer film. The Raman spectrum showed there was little change in the conformation of grafted fibers which mainly remained β-sheet conformation. The IR of the grafted silk fibers showed new absorption of bands occurred which belonged to the stretching-vibrationabsorption-peak bands of Vo-o and VC-F of aliphatic ester species. The CF3-, -CF2- and -CFH- grafted silk macromodecul were verified in the NMR spectrum. The amion acid analysis indicated fluoride monomers were inclined to graft with TYR, ARG and CLU silk fibers.     

Fabrication of PEI-Liposome Loaded Fish Gelatin Nanofibers Mats by Green Electrospinning

Polyethyleneimine （PEI） and cationic liposomes were widely used for gent delivery and the combination of PEI and liposome was reported to result in a higher efficiency of cell transfection in vitro. In recent years, better transfection was observed for the drug-loaded iiposome fixed on the tissue engineering scaffolds via embedding, surface adsorption or covalent grafting thus protected and bound by the scaffolds. In the present study, a novel PEI-liposome loaded fish gdatin composite nanofiber was successfully fabricated by a green electrosplnning process. The existence of PEI- liposome in the composite nanofibers was determined by Fourier transform infrared （ FTIR ） spectra, transmission electron microscopy （TEM）, and confoeal laser scanning microscopy （CLSM）. As shown by scanning electron microscopy （SEM）, the dectrospun composite nanofibers with uniform diameter were smooth and round, and the morphology of the fish gelatin fibers did not change significantly after the incorporation of PEI-liposomes. The transfection results in vitro suggest PEI-liposome loaded fish gelatin material may have a promising application in non-viral gene delivery systems.     

内置式膜式氧合器模型氧合效果的评价

设计了三种不同编排方式的静脉内中空纤维膜式氧合器(IVOX)模型,用Na2SO3的水溶液进行了氧合器的水气传质实验,以Na2SO3的氧化反应来模拟血红蛋白的氧合,并且建立了符合此体系的半经验数学模型,求算相应的血氧交换速率。结果表明,纤维的编排方式对氧合器的氧合效果有显著的影响,网线式的编排具有最好的氧合效果。     

One-Pot Synthesis of Mesoporous Hollow Silica Nanospheres(MHSNS) by Templating Calcium Carbonate

Mesoporous hollow silica nanospheres(MHSNS) with an average diameter of 100 nm and wall thickness of approximately 10 nm were synthesized via core-shell structure of CaCO3@SiO2 by a one-pot route. Hollow silica nanospheres with mesoporous shell were obtained by dissolving CaCO3 in HCl dilute solution. The characterization of as-prepared hollow products by BET indicates that MHSNS have a specific surface area of 865 m2/g and a narrow pore size of 3.78 nm.     

壳聚糖/牛蒡提取物复合膜的制备及应用

为开发新型复合涂膜保鲜剂,以壳聚糖、牛蒡提取物为原料,明胶、甘油为添加剂制备复合膜,并测试其力学性能、抑菌性能、抗氧化性能,同时将复合膜应用于圣女果保鲜中.结果表明:共混液中壳聚糖质量浓度为0.02 g/mL、牛蒡提取物质量浓度为0.1 g/mL、明胶质量浓度为0.03 g/mL、甘油体积分数为0.5 %时制得的复合膜综合性能最佳,抗拉强度为(26.97±2.26)MPa、断裂伸长率为(104.3±5.4)%、羟基自由基清除率为(94.67±4.3)%、抑菌率为(99.32±3.28)%,表面和断裂面比较平整,未出现分相.该复合膜处理的圣女果硬度、可溶性固形物质量分数、VC质量分数、丙二醛(MDA) 质量摩尔浓度均优于壳聚糖单膜处理和未处理的圣女果,且差异显著(P＜0.05).     

Feasibility of Using Chitosan in Nerve Repair

IntroductionChitin,themajorpolysaccharideininsectexoskeletonsandcrustaceanshells,hasβ(1-4)-linkedN-acetylglucosaminerepeatunitsandisthesecondmostabundantformofpolymerizedcarbonfoundinnature[1].Chitosan,thefullyorpartiallyN-deacetyledformofchitin,isacationicpolysaccharidecomposedofglucosamineandN-acetylglucosamineresidueswitha1,4-β-linkage.Ithasastructuresimilartoglycosaminoglycans,whicharethecomponentsofanextracellularmatrixandisbiocompatible[2].Duetoitspositivesurfacechargeandbiocompatibi…     

壳聚糖/玉米淀粉基质复合膜的制备与性能分析

以壳聚糖和玉米淀粉为主要基质,分别加入甘油、聚乙烯醇、明胶和气相二氧化硅,采用溶液共混后流延方法制备食品包装膜。分析了壳聚糖和玉米淀粉的最佳质量比以及添加剂的用量对包装膜力学性能和吸水率的影响。结果表明：当壳聚糖和玉米淀粉质量比为100：214,甘油含量为玉米淀粉质量的20%时,壳聚糖/玉米淀粉膜的综合性能较好;聚乙烯醇含量为玉米淀粉质量的60%、明胶固含量为玉米淀粉质量的10%、气态二氧化硅固含量为玉米淀粉质量的4%时,所得膜在各自系列膜中的性能较佳。