负离子注入技术，因为有着“Charge-up free”的优点，使得在绝缘材料的表面上也不会有电荷积累，一般表面充电电压在正负几伏之间，从而不会形成电荷放电现象。这个优点，使得负离子注入技术相较于正离子注入技术在很多方面有着更好的应用前景，如集成电路、粉末表面改性等。近期这项技术也用于聚合材料细胞相容性改善的研究中。在整形外科临床应用中，硅橡胶（Silicone rubber）因具有优异的理化稳定性、生理惰性、易加工性和耐腐蚀性，目前仍是临床最为常用的填充材料。然而，SR表面呈强烈的疏水性，导致其与组织细胞的相容性较差，使得组织细胞很难与其结合生长。因此，对硅橡胶材料进行合适的材料表面改性，增强其细胞相容性，以提高软组织材料填充后的临床治疗效果，具有重要的意义。在材料表面物理特性的表征中，材料表面的亲水性被认为和细胞相容性有很强的关联，而亲水性可以简单的由水接触角进行表征。本实验对北京师范大学串列加速器实验室GIC4117型串列加速器的前注入器部分进行改装。通过设计安装注入样品台以及静电扫描系统，建立了用于低能负离子及团簇负离子的注入平台。并使用该平台做了碳负离子注入硅橡胶对材料表面细胞相容性改性的研究。通过对硅橡胶样品进行水接触角测量研究了材料亲水性的变化；结合光电子能谱(XPS)，全反射傅里叶红外光谱(ATR-FTIR)，对样品进行定性和定量的分析，通过扫描电镜(SEM)观察了注入前后材料表面形貌的变化情况；最后，在硅橡胶表面进行细胞(HeLa)培养实验。 水接触角测量表明：随着注入剂量增大到1×1016ions/cm2，材料表面的水接触角会从117.6°减小到99.3°，亲水性得到改善。XPS测试表明：随着注量的增加，样品中C含量逐渐减小、而O含量逐渐增加，根据C 1s峰及Si 2p峰的变化，发现注入破坏了硅橡胶中原有的Si-CH4、C-H，同时产生新的官能团如-COOH、-OH、Si-Ox(x=3、4)。ATR-FTIR分析发现注入后Si-CH4、Si-O-Si、C-H键含量均有不同程度的降低，-OH含量升高。基于XPS和FTIR结果，认为负离子注入打断了硅橡胶表面原有的一些疏水的官能团，形成的自由基与空气中的氧原子发生复合反应，形成了亲水的官能团，这是导致其表面亲水性改善的一个原因。SEM观察发现，注入后的硅橡胶表面出现了裂纹和褶皱，使得表面粗糙度增加，这是导致其亲水性改善的另一个原因。最后在样品上进行了细胞培养实验，直观地证明该方法对细胞相容性改善的有效性。

Negative ion-implantation has an advantage of “charge-up free”，for this reason, it doesn’t have charge accumulation on surface of insulator materials during ion implantation. The surface charging voltage is only a few volt, so electric discharge doesn’t happen. For this advantage, negative ion-implantation have more application and prospect in many fields, such as integrated circuit and powder surface modification. Recently, this technology is also used in cell biocompatibility improvement of polymeric material.Because silicone rubber (SR) has excellent stability of physicochemical and physiology, workability and corrosion resistance, it is still the most common filling material in plastic surgery. However, the surface of SR is very hydrophobic, which makes it has bad cell biocompatibility and cell hard to grow with it. Therefore, modifying the surface and improving hydrophilicity of SR is of great significance in improving the property of SR in plastic surgery.In this study, A multi-samples holder and an electrostatic scanner is installed on the injector of the GIC4117 tandem accelerator to establish a negative cluster ion implantation system. Then, the system is used in the study about surface modification of cell biocompatibility of silicone rubber. The measure of water contact angle is used in the research about the change of hydrophilicity. Samples are also Qualitative and quantitative analyzed by X-ray photoelectron spectroscopy (XPS) and Attenuated total reflectance-Fourier transform infrared spectrometry (ATR-FTIR). Scanning electron microscope (SEM) is used for surface morphology observation of the sample. Finally, cells (HeLa) are cultivated on the surface of SR.The measure of water contact angle shows, with an increase in dose up to 1×1016ions/cm2, the contact angle decreased from about 117.6° to 99.3° and surface hydrophilicity is promoted. The XPS results indicate, with an increase in dose, the surface composition of carbon decreased while oxygen increased. The change of C 1s peak and Si 2p peak indicates that ion-implantation breaks Si-CH4 and C-H and generates new functional group such as –COOH, -OH, Si-Ox(x=3,4). ATR-FTIR shows the composition of Si-CH4, Si-O-Si, C-H is decreased while -OH is increased. According to the result of XPS and ATR-FTIR, it can be inferred that ion-implantation break hydrophobic functional group (Si-CH4, Si-O-Si, C-H) of SR and generate hydrophilic functional group (–COOH, -OH, Si-Ox). That is one of reasons which makes the surface of SR more hydrophilic. SEM shows the surface of SR become rough and we think that’s another reason. Finally, cell cultivation proves negative ion-implantation is an effective method to improve the cell biocompatibility.