肝素涂层医用聚氯乙烯的细胞毒性研究

本研究通过肝素—氯烃基二甲基代苯甲胺复合物(A组)、肝素—苯扎溴胺复合物(B组)和肝素—聚乙烯亚胺复合物对医用聚氯乙烯体外循环管道进行了肝素涂层,同时采用材料直接接触细胞培养法和四唑盐(MTT)比色试验评价各种涂层材料的细胞毒性。结果显示A、B组材料直接接触L-929细胞后24h即引起细胞大量死亡,而C组材料直接接触后具有良好的细胞相容性。MTT比色试验也表明A、B两种涂层材料具有较低的OD值。A、B两种涂层材料具有较强的细胞毒性,而C方法处理的聚氯乙烯材料不引起细胞死亡,具有进一步临床应用前景。     

起搏器封装用环氧树脂材料的细胞毒性研究

对两种环氧树脂进行细胞毒性研究,探讨环氧树脂对L929成纤维细胞的细胞增殖影响,为其在植入式人工心脏起搏器的封装应用提供依据.按照GB/T 16886制备样品及材料的浸提液,在48 h、72 h、96 h对细胞生长状况进行拍照观察,并通过MTT方法,检测材料浸提液对成纤维细胞的细胞毒性作用,根据细胞相对增值率,对材料毒性进行分级.细胞在两种环氧树脂浸提液中生长正常,细胞形态良好,实验期内浸提液对成纤维细胞的相对增殖率均在90%以上,材料细胞毒性分级为0-1级.说明实验选用的两种环氧树脂与L929细胞相容性良好,无细胞毒性,符合心脏起搏器植入材料的细胞毒性要求.     

三种比色法评价4种牙科金属材料对L-929细胞的毒性

背景：采用不同方法评价材料的细胞毒性可能会得出不同的实验结果。 目的：采用3种比色法评价镍铬合金、钴铬合金、3铬13及纯钛等牙科金属材料对小鼠成纤维细胞(L-929细胞)的细胞毒性。 方法：以镍铬合金、钴铬合金、3铬13及纯钛4种牙科金属材料的浸提液分别作用于体外培养的L-929细胞24,72 h。以体积分数10%小牛血清+高糖DMEM培养液培养的L-929细胞为阴性对照组,以0.7%丙烯酰胺+体积分数10%小牛血清+高糖DMEM培养液培养的L-929细胞为阳性对照组,分别采用MTT、CCK-8及结晶紫3种比色法检测上述材料的细胞毒性。 结果与结论：①4种材料浸提液中培养的细胞形态正常,胞内结构清晰,随着培养时间延长细胞大量增殖,与阴性对照组细胞形态无明显差异。阳性对照组细胞数量明显减少,形态完整性受破坏,形成大量细胞碎片。②培养24 h时,CCK-8比色法检测中钴铬合金组的细胞相对增殖率低于阴性对照组(P < 0.05),MTT及结晶紫比色法检测中钴铬合金组的细胞相对增殖率与阴性对照组比较差异无显著性意义(P > 0.05);培养72 h时,MTT比色法检测中4种牙科金属材料组细胞相对增殖率低于阴性对照组(P < 0.01),CCK-8及结晶紫比色法检测中4组的细胞相对增殖率与阴性对照组比较差异无显著性意义(P > 0.05),但材料细胞毒性均为0-1级。表明上述4种牙科金属材料细胞毒性均在临床应用的允许范围内,具有良好的生物安全性。     

肝素涂层体外循环管道的制备及生物学性能评价

通过离子键方式将肝素分子结合于体外循环医用聚氯乙烯管道中 ,进行了体外转流抗凝血性能测定和细胞毒性、肌肉植入等生物学性能评价 ,结果显示肝素分子结合于聚氯乙烯材料表面 ,同时筛选出具有抗凝血活性和良好生物相容性的聚乙烯亚胺 肝素涂层方法。     

纳米载银磷酸锆抗菌聚氨酯的细胞毒性检测

背景：聚氨酯是一种研究热门的医用高分子材料,并在许多人工器官和医疗装置中发挥着至关重要的作用。 目的：制备并观察纳米载银磷酸锆抗菌聚氨酯生物材料对L929细胞增殖活性的影响及细胞毒性反应。 方法：采用MTT法检测各组抗菌聚氨酯对传代培养小鼠成纤维细胞L929的细胞毒性,L929细胞接种于96孔板,随机分为3组进行培养,实验组用抗菌聚氨酯浸提液处理,阳性对照组用苯酚溶液,阴性对照组用高密度聚乙烯浸提液,于24,48,72 h后在倒置相差显微镜下观察细胞形态,通过MTT比色法检测各组细胞的相对增殖率,并评价材料的细胞毒性。 结果与结论：实验组作用于小鼠成纤维细胞24,48,72 h后,相对增殖率分别为94.3%~97.9%,94.5%~99.8%和90.8%~96.3%,材料细胞毒性评级为Ⅰ级。提示添加低浓度纳米载银无机抗菌剂RHA-2(添加比例<5%)的热塑性聚氨酯,无细胞毒性,符合医用生物材料安全标准。     

人工气管组分材料的毒理学评价

目的 对人工气管的相关组分材料进行毒理学评价实验.方法 本实验按照国际国内既定标准,对纳米碳纤维、胶原蛋白-纳米羟基磷灰石等组分材料进行体外毒理学实验研究,包括细胞毒性实验、遗传毒性实验、急性毒性实验.结果 本实验涉及的生物材料以及混合材料没有发现细胞毒性及遗传毒性作用.各组材料浸渍液与L-929细胞共培养7 d,细胞相对增殖率均>100%(纳米碳纤维:136.21%;胶原蛋白.纳米羟基磷灰石:135.10%;混合材料:112.05%),毒性分级均为0级.动物实验亦未见明显的全身毒性作用,均符合毒理学评价实验的安全标准.结论 利用纳米碳纤维、胶原蛋白-纳米羟基磷灰石设计制作的人工气管符合生物相容性毒理学评价实验的安全标准.     

新型医用无镍不锈钢的生物相容性评价

背景：BIOSSN4无镍不锈钢是一种奥氏体医用不锈钢材料,在中国药品生物制品检定所通过了标准的溶血实验、细胞毒性实验和致敏实验。 目的：评价新型医用BIOSSN4无镍不锈钢的体外细胞毒性及抗腐蚀性。 方法：将小鼠L929成纤维细胞悬液以1×108 L-1的浓度接种于96孔板,分5组培养,分别加入BIOSSN4无镍不锈钢浸提液、316L不锈钢浸提液、金合金浸提液、铅材料浸提液(阳性对照)及RPMI1640培养液(阴性对照)。培养1,2,3 d,观察细胞形态,采用MTT法检测各组吸光度值,计算细胞相对增殖率,评价毒性分级。在模拟口腔环境中,检测BIOSSN4无镍不锈钢、316L不锈钢及金合金的自腐蚀电位、自腐蚀电流密度及极化电阻。 结果与结论：培养3 d内,铅材料浸提液组细胞皱缩,细胞数量明显减少,细胞相对增殖率低于其余4组(P < 0.05);其余4组细胞形态良好,增殖旺盛,细胞相对增殖率均在75%以上。BIOSSN4无镍不锈钢浸提液、316L不锈钢浸提液与金合金浸提液的毒性均为1级,铅材料浸提液的毒性为2至3级,表明BIOSSN4无镍不锈钢具有良好的生物相容性。BIOSSN4无镍不锈钢的抗腐蚀性高于316L不锈钢,低于金合金。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

温敏性壳聚糖水凝胶对大鼠成骨细胞的毒性

背景：温敏性壳聚糖与多种细胞相容性良好,是组织工程中不可多得的优良载体,但其对成骨细胞毒性研究相对缺乏。 目的：验证温敏性壳聚糖水凝胶对成骨细胞的毒性。 方法：成骨细胞在温敏性壳聚糖水凝胶中进行培养,显微镜下观察细胞形态及扩增情况,同时,SD大鼠成骨细胞在不同浓度的温敏性壳聚糖水凝胶浸提液中体外培养24,48,72,96 h,MTT法测定细胞相对增殖率,判断细胞毒性的级别。 结果与结论：SD大鼠成骨细胞在温敏性壳聚糖水凝胶中培养24 h内镜下观察呈圆形,48 h后开始伸出触角并扩增;温敏性壳聚糖水凝胶浸提液中培养的各组细胞在不同时间点相对增殖率在92%~112%之间,各浓度的温敏性壳聚糖水凝胶材料浸提液的细胞毒性均为0级或1级,完全符合生物材料的安全评价标准。     

MTT法评价肝素涂层医用聚氯乙稀的细胞毒性

目的　评测 3种肝素涂层医用聚氯乙稀材料的细胞毒性。方法　采用肝素氯烃基二甲基代苯甲胺复合物(HBC)、肝素苯扎溴胺复合物 (HBB)和肝素聚乙烯亚胺复合物 (HPEI) 3种方法对医用聚氯乙稀材料进行肝素涂层 ;根据国家标准提取各种材料的浸提液 ;通过体外细胞培养 ,四唑盐 (MTT)比色法评价各种涂层材料的细胞毒性。结果　HBC和HBB方法涂层的医用聚氯乙稀材料具有较低的光吸收 (OD)值 ,而HPEI方法涂层的医用聚氯乙稀材料OD值高于其它 2组 (P <0 .0 1) ,并随时间延长呈上升趋势。结论　HBC和HBB 2种方法涂层的医用聚氯乙稀材料具有较强的细胞毒性 ,而HPEI方法处理的聚氯乙稀材料细胞相容性好 ,具有进一步应用前景     

MTT法评价医用高分子材料的细胞毒性

为研究医用高分子材料的细胞毒性，采用能快速评定细胞增殖率和细胞毒性的比色分析方法-MTT比色法，分别检测三类医用高分子材料的浸提液对小鼠成纤维细胞L929细胞相对增殖率的影响，评价其细胞毒性。参照美国药典的评价标准，三类医用高分子材料均呈现出高的细胞相对增殖率，其细胞毒性为l级，即无细胞毒性。     

不同浸提介质对一次性使用球囊扩张导管体外细胞毒性评价的影响

研究不同浸提介质对一次性使用球囊扩张导管体外细胞毒性评价的影响。采用不同的浸提介质制备了一次性使用球囊扩张导管浸提液,以MTT法评价浸提液对小鼠成纤维细胞L929活性与增殖的影响,计算相对增殖率（RGR）。一次性使用球囊扩张导管不同浸提液之间的OD值存在差异,四种浸提液的RGR值均〉80%,细胞毒性均为1级。选择含血清的MEM是评价介入类医疗器械体外细胞毒性实验的理想浸提介质。     

Effect of biologically active coating on biocompatibility of Nitinol devices designed for the closure of intra-atrial communications

Anti-thrombogenicity and rapid endothelialisation are prerequisites for the use of closure devices of intra-atrial communications in order to reduce the risk of cerebral embolism. The purpose of this study was therefore to assess the effect of bioactive coatings on biocompatibility of Nitinol coils designed for the closure of intra-atrial communications. Nitinol coils (n = 10, each) and flat Nitinol bands (n = 3, each) were treated by basic coating with poly(amino-p-xylylene-co-p-xylylene) and then coated with either heparin, r-hirudin or fibronectin. Anti-thrombogenicity was studied in vitro in a dynamic model with whole blood by partial thromboplastin time (PTT), platelet binding and thrombin generation, respectively, and cytotoxicity by hemolysis. Endothelialisation was studied on Nitinol bands with human umbilical venous endothelial cells (HUVEC) by 3-(4,5-dimethylthiazole-2yl)-2,5-triphenyl tetrazolium (MTT) assay and immnuofluorescence analysis of Ki67, vinculin, fibronectin and von Willebrand Factor. Uncoated or coated devices did not influence hemolysis and PTT. r-Hirudin (but not heparin) and fibronectin coating showed lower platelet binding than uncoated Nitinol (p < 0.005, respectively). Heparin and r-hirudin coating reduced thrombin formation (p < 0.05 versus Nitinol, respectively). HUVEC adhesion, proliferation, and matrix formation decreased in the order: fibronectin coating > uncoated Nitinol > r-hirudin coating > heparin coating > basic coating. MTT assay corroborated these findings. In conclusion, r-hirudin and fibronectin coating, by causing no acute cytotoxicity, decreasing thrombogenicity and increasing endothelialisation improve in vitro biocompatibility of Nitinol devices designed for the closure of intra-atrial communications.     

Novel quantitative methods for the determination of biomaterial cytotoxicity.

Two novel methods for the determination of biomaterial cytotoxicity using cell culture are presented. The methods combine a standardized protocol for producing extracts from medical devices with either the established MTT assay or a new fluorimetric assay. The suitability of both methods for evaluating the toxicity of candidate materials was demonstrated by resolution of the differences in the toxic effects of serial dilutions of a PVC extract on BHK21 and HT1080 cells. The tests yield highly reproducible, quantitative results and can be applied to materials in the usual physical forms applicable to artificial organs.     

Coating of commercially available materials with a new heparinizable material.

Different commercial materials, such as polyurethane (PU), plasticized PVC (PVC), glass, Gore-tex, and Dacron, were coated with a well-characterized biomaterial (PUPA) based on polyurethane and poly(amido-amine) components. Two different classes of coating were obtained due to the different characteristics of the substrates. In the case of PVC and polyurethane which are soluble in the solvent of the PUPA-coating solution, there was penetration and blending of the coating and underlying materials. In the case of glass, Gore-tex, and Dacron, which are insoluble in the solvent of the coating solution, only a superficial layer of PUPA could be obtained. The coating stability was investigated and the interaction between coating and underlying material studied by FT-IR. All the stable coatings showed the ability to bind as much heparin as PUPA material by itself.     

Effect of dental material HEMA monomer on human dental pulp cells

The purpose of this study was the cytotoxicity assay of dental material HEMA monomer to human dental pulp cell by MTT method and application of the flow cytometry to analyze effect of dental material on the cell cycle progression. The result of MTT method showed the inhibition of cell growth and 50% inhibitory concentration (IC50) of HEMA monomer in human dental pulp cell was 815.19 micrograms/ml. The result of the flow cytometry showed that there was a perturbation on human dental pulp cell cycle progression at the phases of Sand G2M with a dose-dependent manner. Biomaterials including dental materials should be safety to human bodies. Presently, many methods for testing the cytotoxicity of biomaterials were suggested. [1-2] MTT method is one of the cytotoxicity assay. It was provided by Monsmnn. [3] MTT is a kind of tetrazolium salt [3-(4,5-dimethylthiazol-2yi)-2,5-diphenyl tetrazolium bromide]. MTT method is the rapid, precision and quantitative colorimetric assay for cytotoxicity. It can be used to measure the proliferation, cytotoxicity or activation of living cells and is capable of handling large number of samples. Many investigators have used this advanced method.[4] Flow cytometry (FCM) analyzes the quantity of DNA bonded with dyes in each cell. It can provided the information of the cell cycle progression in detail. Currently, flow cytometry has been widely and successfully used in various fields of basic science research and clinical medicine. This FCM technology also can be used to study the cytotoxicity of dental materials and evaluate the biocompatibility of dental materials.[5-6] The contents of the study were (1) cytotoxicity assay on dental material HEMA monomer in human dental pulp cells by MTT method. (2) application flow cytometry to analyze the effect of dental material HEMA monomer on the cell cycle progression of the human dental pulp cells.