碳纳米管/聚氨酯复合材料的制备及生物相容性评价

目的 制备和评价碳纳米管/聚氨酯复合材料的生物相容性。方法 通过溶胶-凝胶方法制备碳纳米管/聚氨酯复合材料,对其力学性能进行测试;根据ISO10993指南,选取溶血实验、动态凝血实验、血小板黏附实验、血小板活化实验、细胞毒性实验和材料局部植入方法对复合材料的生物相容性进行评价。结果 复合材料无明显细胞毒性,并表现出比聚氨酯材料更好的抗溶血性能、动态凝血性能、抑制血小板黏附性能以及组织相容性。结论 碳纳米管－聚氨酯复合材料具有优良的生物相容性,可以作为制备组织工程细胞生长支架、人工血管、药物载体的基础材料。     

两种交联剂制备软骨细胞移植支架的比较

目的：试用两种交联剂对小牛真皮基质来源的支架材料进行交联,比较支架的细胞毒性、结构、生物相容性和细胞贴附的差异,为在体动物试验提供实验依据。方法将脱细胞真皮基质分为两组,分别浸入0.05%戊二醛溶液和0.2%水溶性交联剂进行交联,MTT 法检测细胞毒性和溶血率。将交联后的支架分别植入大鼠皮下,评价生物相容性。以排液法粗测孔隙率,并在电镜下观察支架的结构和孔隙大小。培养间充质干细胞并贴附于两种方法处理的材料表面,电镜下观察贴附情况。结果以戊二醛溶液和水溶性交联剂两种方法处理的支架细胞毒性检测均合格,溶血率分别为4.61%与2.97%,均符合国家标准。经戊二醛交联的支架生物相容性差,炎症反应始终存在,水溶性交联剂处理的真皮基质组织相容性较好,仅有轻微的炎症反应。水溶性交联剂制备的支架材料孔隙率为84.3%±5.0%,戊二醛制备的支架材料孔隙率为79.7%±10.8%,差异不具有统计学意义（P >0.05）。戊二醛交联的支架细胞贴附差,而水溶性交联剂制备的支架细胞贴附良好。结论应用水溶性交联剂处理的支架细胞毒性和溶血率检测均合格,具有良好的生物相容性、孔隙率和细胞贴附性,该法可以作为后期制备软骨细胞移植支架的交联方法。     

人角膜接触镜材料生物相容性的研究

目的研究本室制备的人角膜接触镜材料的生物性能。方法采用细胞毒性试验、红细胞溶血试验以及蛋白质沉积试验方法。结果所制备的人角膜接触镜材料对人胚肺纤维细胞(HEFC)毒性评价为1级无毒性;红细胞溶血率为1.62%合格;在体温范围内抗蛋白质沉积作用较好。结论本室制备的人角膜接触镜材料具有较好的生物相容性。     

人角膜接触镜材料生物相容性的研究

目的 研究本室制备的人角膜接触镜材料的生物性能.方法 采用细胞毒性试验、红细胞溶血试验以及蛋白质沉积试验方法.结果 所制备的人角膜接触镜材料对人胚肺纤维细胞(HEFC)毒性评价为1级无毒性;红细胞溶血率为1.62%合格;在体温范围内抗蛋白质沉积作用较好.结论 本室制备的人角膜接触镜材料具有较好的生物相容性.     

多孔铌基生物材料的制备及其性能研究

目的 制备多孔铌并评价其相关性能.方法 采用新型的泡沫浸渍法,以聚氨酯泡沫为载体制备出具有较高强度和良好生物相容性的多孔铌基材料.并借助分析天平、XRD、CS600碳硫测试仪和SEM对多孔铌的孔隙率、性能和微观结构进行了测试及观察,运用细胞生物学技术评价多孔铌的细胞生物相容性.结果 多孔铌具有三维、连通孔隙结构且无任何杂质相,孔隙率为71.4％,孔径500 μm,平均密度为2.45 g/cm3,具有与人体松质骨相匹配的弹性模量和抗压强度;多孔铌不影响成骨细胞的增殖、黏附和表型表达.结论 多孔铌具有高孔隙率结构,良好的力学性能及细胞生物相容性.     

新型生物可吸收房间隔缺损封堵器的生物相容性研究

目的评价自主研究的新型房间隔封堵器的生物相容性,为动物实验提供依据。方法封堵器框架由生物可吸收聚左旋乳酸(poly-L-lactic acid,PLLA)单丝网编织成型。通过对PLLA单丝进行体外细胞毒性测试、体外溶血测试、全身急性毒性测试、肌肉植入实验,评价新型房间隔封堵器的生物相容性。结果 PLLA房间隔缺损封堵器无体外细胞毒性,体外溶血率0.9%,无急性全身毒性反应。通过分析样品植入肌肉1个月、3个月和6个月后组织病理,观察样品与组织之间的反应,未发现明显的组织损伤和组织增生。结论生物可吸收PLLA房间隔封堵器的生物相容性良好,可进行下一步的动物实验研究。     

甲壳素短纤维增强聚己内酯复合材料的制备及生物学评价

用共混法制备甲壳察短纤维增强聚己内酯复合材料，并对纯聚己内酯和甲壳察短纤维增强聚己内酯复合材料进行体外细胞毒性和生物相容性评价，为临床应用提供有价值的实验依据。对该两种材料进行体外细胞毒性试验、急性全身毒性试验、溶血试验、热源试验和过敏试验。结果显示受试材料最终细胞毒性级为0级，对细胞生长和增殖无明显抑制作用，材料中不存在潜在致敏性物质，浸提液无溶血反应和急性全身毒性反应，无热源反应，表明该复合材料具有良好的细胞和组织相容性，其作为胸壁缺损修补材料应用于临床具有可行性和安全性。     

交联透明质酸凝胶膜的制备及其生物相容性的研究

制备交联透明质酸凝胶膜并评价其生物相容性.本研究采用己二酸二酰肼作为交联剂制备交联透明质酸凝胶膜,并采用GB/T16886医疗器械生物学评价标准规定的方法,对凝胶膜进行体外溶血试验、细胞毒性试验、急性毒性试验、眼刺激试验、皮内反应试验、致敏试验以及鼠伤寒沙门氏菌回复突变试验、哺乳动物培养细胞染色体畸变试验和小鼠骨髓嗜多染红细胞微核试验等三项遗传毒性试验.结果表明交联透明质酸凝胶膜无溶血性、无眼刺激作用、无皮内刺激和致敏作用,未见急性毒性反应,细胞毒性0～1级;三项遗传毒性试验均为阴性.交联透明质酸凝胶膜具有良好的生物相容性,是一种理想的医用生物材料.     

一种眼巩膜生物补片的制备及生物相容性研究

目的 制备一种适用于眼后巩膜加固术的新型生物补片,通过对其生物相容性进行研究,评价其生物安全性.方法 首先采用新鲜的牛心包经去除表面脂肪组织、脱细胞、扩孔和梳整后,与京尼平进行生物交联,制备出一种眼巩膜生物补片.然后进行体外细胞毒性试验、溶血试验、皮内反应试验、皮肤致敏试验、急性全身毒性试验和植入试验,通过检测细胞存活率、溶血率、皮内反应记分、皮肤致敏反应等级、毒性反应和植入刺激指数分析眼巩膜生物补片的生物相容性.结果 眼巩膜生物补片无细胞毒性反应、无潜在的动物皮内刺激和肌肉刺激作用、无皮肤致敏性和无急性全身毒性反应;溶血率符合要求.结论 通过扩孔和梳整工艺等技术所制备的眼巩膜生物补片具有良好的生物相容性,符合国家相关标准要求,为其在临床上眼后巩膜加固术中的安全应用提供参考.     

肌腱缝合线生物相容性的实验研究

为了解肌腱缝合线的生物相容性，在细胞毒性实验的基础上，进行了全身急性毒性试验、热原试验、皮肤刺激试验、溶血试验等生物学研究。根据标准对试验数据进行分析和评估。结果显示人工肌腱缝合线的急性毒性试验、溶血试验、热原试验、皮肤刺激试验均为阴性，表明此种缝合线的生物相容性良好，是理想的医用生物材料。     

The role of reactive silicates on the structure/property relationships and cell response evaluation in polyurethane nanocomposites

Precursors of polyurethane chains have been reacted by means of in situ polymerization with organically modified montmorillonite clay to obtain polyurethane nanocomposites containing from 1 to 4 wt % of nanoreinforcement. The effective final dispersion of inorganic component at nanometric scale was investigated by X-ray diffraction, atomic force microscopy, and transmission electron microscopy. In addition, the effect of the nanoreinforcement incorporation on thermal and mechanical behavior of polyurethane nanocomposites was evaluated. Nanocomposites showed similar mechanical properties to polyurethanes containing high-hard segment contents with higher tensile modulus and a decrease in elastomeric properties of polyurethane materials. Finally, biocompatibility studies using L-929 fibroblast have been carried out to examine in vitro cell response and cytotoxicity of the matrix and their nanocomposite materials. Results suggested that the organic modifier in the clay is unsuitable for biomedical devices in spite of the fact that the matrix is a good candidate for cell adhesion and proliferation.     

Development of biodegradable polyurethane and bioactive glass nanoparticles scaffolds for bone tissue engineering applications

The development of polymer/bioactive glass has been recognized as a strategy to improve the mechanical behavior of bioactive glass-based materials. Several studies have reported systems based on bioactive glass/biopolymer composites. In this study, we developed a composite system based on bioactive glass nanoparticles (BGNP), obtained by a modified St?ber method. We also developed a new chemical route to obtain aqueous dispersive biodegradable polyurethane. The production of polyurethane/BGNP scaffolds intending to combine biocompatibility, mechanical, and physical properties in a material designed for tissue engineering applications. The composites obtained were characterized by structural, biological, and mechanical tests. The films presented 350% of deformation and the foams presented pore structure and mechanical properties adequate to support cell growth and proliferation. The materials presented good cell viability and hydroxyapatite layer formation upon immersion in simulated body fluid.     

In Vitro Biocompatibility Evaluation of Novel Urethane–Siloxane Co-Polymers Based on Poly(ϵ-Caprolactone)-block-Poly(Dimethylsiloxane)-block-Poly(ϵ-Caprolactone)

Abstract

Novel polyurethane co-polymers (TPUs), based on poly(?-caprolactone)-block-poly(dimethylsiloxane)-block-poly(?-caprolactone) (PCL-PDMS-PCL) as soft segment and 4,4’-methylenediphenyl diisocyanate (MDI) and 1,4-butanediol (BD) as hard segment, were synthesized and evaluated for biomedical applications. The content of hard segments (HS) in the polymer chains was varied from 9 to 63 wt%. The influence of the content and length of the HS on the thermal, surface, mechanical properties and biocompatibility was investigated. The structure, composition and HS length were examined using ¹H- and quantitative ¹³C-NMR spectroscopy. DSC results implied that the synthesized TPUs were semicrystalline polymers in which both the hard MDI/BD and soft PCL-PDMS-PCL segments participated. It was found that an increase in the average HS length (from 1.2 to 14.4 MDI/BD units) was accompanied by an increase in the crystallinity of the hard segments, storage moduli, hydrophilicity and degree of microphase separation of the co-polymers. Depending on the HS content, a gradual variation in surface properties of co-polymers was revealed by FT-IR, AFM and static water contact angle measurements. The in vitro biocompatibility of co-polymers was evaluated using the endothelial EA.hy926 cell line and protein adsorption on the polyurethane films. All synthesized TPUs adsorbed more albumin than fibrinogen from multicomponent protein mixture, which may indicate biocompatibility. The polyurethane films with high HS content and/or high roughness coefficient exhibit good surface properties and biocompatible behavior, which was confirmed by non-toxic effects to cells and good cell adhesion. Therefore, the non-cytotoxic chemistry of the co-polymers makes them good candidates for further development as biomedical implants.     

Evaluation of the in vitro biocompatibility of various elastomers

A previous study highlighted the superior shock absorption of silicone rubbers compared to other elastomers. We evaluated and compared the in vitro biocompatibility of silicone-based rubbers and propose them as an alternative to conventional products. We used the MTT colorimetric test to assess cell viability and flow cytometry to evaluate cell proliferation. Tests were conducted at 24 and 72 h. Changes in cell morphology were evaluated by scanning electron microscopy. Positive (polyurethane) and negative (polystyrene) toxicity controls were included. The number of viable cells was significantly higher on polystyrene than on polyurethane. A decrease in the total number of cells from 24 to 72 h compared to the negative control was correlated with a lower percentage of S-phase cells. The differences in cell viability noted between the samples and the polystyrene control mainly resulted from an initial lack of adhesion, which was confirmed by scanning electron microscopy. The biocompatibility of the three silicone rubbers was comparable to the best of the three products currently being used. These results, combined with those of the previous study, indicate that silicone rubber could be considered for the manufacture of mouth guards.     

基于丝素/胶原/羟基磷灰石仿生骨材料的多维结构及其性能

目的 体外构建丝素蛋白（silk fibroin,SF）、I型胶原(type I collagen,Col-I)和羟基磷灰石(hydroxyapatite, HA)共混体系制备二维复合膜和三维仿生支架,研究其理化性质和生物相容性,探讨其在组织工程支架材料中应用的可行性。方法 通过在细胞培养小室底部共混SF/Col-I/HA以及低温3D打印结合真空冷冻干燥法制备二维复合膜及三维支架。通过机械性能测试、电子显微镜和Micro-CT检测材料的理化性质,检测细胞的增殖评估其生物相容性。结果 通过共混和低温3D打印获得稳定的二维复合膜及三维多孔结构支架;力学性能具有较好的一致性,孔径、吸水率、孔隙率和弹性模量均符合构建组织工程骨的要求;支架为网格状的白色立方体,内部孔隙连通性较好; HA均匀分布在复合膜中,细胞黏附在复合膜上,呈扁平状;细胞分布在支架孔壁周围,呈梭形状,生长及增殖良好。结论 利用SF/Col-I/HA共混体系成功制备复合膜及三维支架,具有较好的孔连通性与孔结构,有利于细胞和组织的生长以及营养输送,其理化性能以及生物相容性符合骨组织工程生物材料的要求。     

小口径组织工程血管基质材料的生物学和力学评价

目的研制一种具备正常血管的生理结构和良好的生物相容性,而且具有血管力学特性的小口径组织工程血管基质材料,并按医用输血材料的力学及生物学国家标准评价。方法以去细胞生物衍生材料作为基质,按照国家标准对其进行力学和生物学评价。结果血管的轴向、径向拉伸应力分别为23.14 N和36.79 N,均大于标准规定的7.5 N;拉伸率分别为95.19%和80.24%,大于标准规定的20%。血管的缝合强度为13.71 N,不小于0.5 N,血管符合力学规定。生物学检测主要用血管或其浸提液检测血管的pH值在对照去离子水pH(7.52±1.5)范围内、溶血率1.397 2%,小于5%、全血凝固时间比对照长50%、对细胞毒性为0级,皮内注射无刺激。结论血管基质材料具有良好的力学及生物学性能,它将在小口径血管替代治疗中起重要作用。     

医用级硅凝胶的生物学实验研究

有机硅凝胶(GNY—514,GNY—515)具有较好的物理机械性能而被用于医学各个领域,但对该材料的毒性及生物相容性研究报道较少,作者参考了有关标准,对硅凝胶材料及制品进行了系统的毒性及生物相容性研究。结果表明红外分析制品内未查出残留单体,从细胞培养试验证实无细胞毒性,Ames试验未见致突变现象,三种刺激试验表明均无刺激反应,硅凝胶的四种介质浸提液无急性毒性反应,小鼠微核试验微核率正常,材料肌肉植入无明显的组织学改变。该研究结果证明了硅凝胶材料是无毒、无刺激、生物相容好的生物医用材料。     

封闭式负压引流(VSD)急诊治疗大面积皮肤脱套伤患者1例

目的报道下肢皮肤脱套伤的手术方法及疗效。方法应用全厚皮片原位回植加封闭式负压引流﹙VSD﹚技术治疗下肢皮肤脱套伤。结果术后回植皮片成活率98%,伤肢的色泽、外形、功能恢复满意,感觉恢复良好。结论应用全厚皮片原位回植加封闭式负压引流﹙VSD﹚技术治疗大面积皮肤脱套伤是一种安全、有效的方法,值得推广应用。     

九种医用金属材料的生物相容性

作者对九种金属材料:包括四种316L不锈钢,三种钛金属及二种钴铬钼合金材料,采用体外鸡胚股骨培养法和细胞毒性试验法进行了生物相容性评价,并将其中六种材料作了溶血试验,急性毒性试验及热源试验。 实验结果表示:九种金属材料在鸡胚股骨培养及细胞毒性试验中毒性低,其中六种金属材料的急性毒性、溶血及热源试验全部合格。这为筛选出较优良的临床使用材料,提供了一定的依据。     

Polyurethane-covered mammary prosthesis: a nine year follow-up assessment.

We have examined ten tissue capsules from patients ranging from five months to nine years of mammary implantation. Contrary to published reports of polyurethane foam "fragmentation" or "disappearance" in the capsules evaluated, the polyurethane foam was still present and embedded in the surrounding tissue capsule. The foam was nearly always invisible by gross observation, or manual palpation. Only after enzymatic digestion of the tissue capsule did the foam become clearly visible as continuous sheets. ESCA analyses show that explanted foams are devoid of nitrogen peaks. Only carbon, oxygen and silicone signals are observed. The same foams do show nitrogen peaks (due to urethane linkages) when probed by FTIR. Since ESCA only analyzes the first 40-50 Angstroms of a surface, we believe that a "protective coating" composed of soft segments has formed. Beneath this "coating" the original polyurethane composition is still present as evidenced by FTIR analysis. Three possible explanations are advanced: (1) The surface hydrolysis, which takes place within the soft segment of the polyurethane polymer, results in the formation of oligomer(s). These oligomers, devoid of urethane linkages, appear to protect the polymer from further bioresorption, by significantly retarding the rate of additional surface hydrolysis. (2) Chain cleavage occurs in the soft segment producing a hydrophilic polyester chain end which orients into the interfacial area. These chain ends then produce a skin effect which increases the distance from the surface to the hard segments, or urethane-containing linkages. (3) Macromolecular motion in the soft segment phases of the polymer could be reorienting under the influence of the in vivo environment, thus producing a surface layer or "coating" which is predominantly soft segment in composition. Regardless of which of the three hypotheses proves to be most plausible, we interpret the data as showing that the polyurethane foam cover undergoes very slow bioresorption, even after 9 years of human implantation. The data further suggests that the in vivo surface of the polyurethane foam cover is biocompatible and interfacial interactions with inflammatory cells are downregulated or reduced because of the apparent biocompatibility of the material.