纳米铁显影增强硅橡胶的制备及影像可视性评价

Preparation and X-ray visibility evaluation of radiopacity enhanced silicone rubber by ironic nanopartides

目的 探讨纳米铁微粒作为显影标记物对医用硅橡胶改性的可行性并评价复合材料的影像可视性.方法 硅油与纯铁粉、碳包铁粉混合,按预定的配方比分别与甲基乙烯基硅橡胶共混、密炼、模压、硫化,得到纳米纯铁粉增强硅橡胶（第1组）、纳米碳包铁粉增强硅橡胶（第2组）,空白对照组为医用硅橡胶.CT扫描体外各组材料试件,获取图像并测得CT值,比较组间CT值均值的差异性;将2组材料试件植入犬皮下,获得标准X-线图像;X射线衍射技术分析材料内铁微粒的组分稳定性.结果 分别制备出铁粉显影增强硅橡胶和碳包铁粉显影增强硅橡胶,新材料在体内外的X-线图像清晰可见,复合材料的CT值随金属纳米粉体量和纳米微粒原子量的增加而增加,2组材料的CT值均值、组间配方比相同的材料的CT值均值差异显著（P＜0.001）;材料放置180 d后,单质铁出现衍射峰的位置基本没有变化,分散在硅橡胶中的纳米纯铁微粒、碳包铁微粒较为稳定.结论 金属纳米铁粉、碳包铁粉可作为硅橡胶显影性改良的标记物.

Objective To explore the feasibility of iron nanoparticles as radiopaque agents for modifying medical silicone rubber and to evaluate image visibility of modified materials.Methods Methyl vinyl silicone elastomer was mixed with iron nanoparticles,carbon-coated ferric nanoparticles,respectively,in accordance with the designed formula ratios.The composites were blended,mixed,molded and vulcanized with.Two groups of new materials,iron nanoparticle enhanced silicone rubber （INESR,Group1） and carbon-coated ferric nanoparticle enhanced silicone rubber（Fe/CESR,Group2）,were harvested.Medical silicone rubber was as a negative control group.CT scanning of each group of material samples in vitro was performed,and both CT images and measured CT values were collected.Differences in CT mean values between the groups were compared.Samples of new material groups were implanted subcutaneously in a dog and standardized radiographic images were obtained.X-Ray Diffraction was used to analyze the component stability of iron nanoparticles dispersing in the silicone rubber.Results Two groups of radiographic image enhanced silicone rubber were prepared.The X-ray images of new composites were clearly visible both in vitro and in vivo.CT values were increased with the increase of added metal nanoparticles and metal atomic weight.CT mean values of each group and the materials in Group 1 and Group2 with the same material formulation were significantly different （P〈0.001）.After placed for 180 days,the diffraction peak positions of elemental iron in both groups of materials remained essentially unchanged,and it showed that dispersed iron nanoparticles and carbon-coated iron nanopaarticles in silicone rubber were stable.Conclusion The metal nanoparticles of iron and carbon-coated ferrum can be used as radiographic markers for improving quality of X-Ray image of the medical silicone rubber.