钛表面接枝 大分子季铵盐抗菌性的研究

目的:在钛表面接枝大分子季铵盐,以增强钛种植体的表面抗菌效果。方法:采用表面引发原子转移自由基聚合反应(ATRP)引发甲基丙烯酸 N,N-二甲氨基乙酯 (DMAEMA)单体在钛片表面聚合,获得含叔胺基团的高分子聚合物刷,然后与十六烷基溴发生季铵化反应,在钛表面形成通过共价键连接的季铵盐涂层。用用静态接触角仪、傅立叶红外光谱仪(FTIR)、X射线光电子能谱(XPS)对改性的钛表面进行表征;以纯钛为对照组,季铵化后的钛片作实验组,分别在其表面进行变形链球菌(S.m)和大肠杆菌(E. coli )培养,4、 24 h后用荧光显微镜和扫描电镜 检测钛片表面的细菌活性。 结果:静态接触角仪、傅立叶红外光谱仪、X射线光电子能谱仪等结果证明大分子季铵盐被接枝到钛片表面。荧光显微镜显示无论是G⁺变形链球菌还是G^-大肠杆菌,纯钛表面均有大量的活细菌;而实验组上细菌几乎全为死菌。SEM显示实验组钛片表面的细菌比空白组钛表面量明显少些,结果与荧光显微镜结果一致。结论:钛表面成功接枝大分子季铵盐物季铵盐,接枝大分子季铵盐的钛表面对变形链球菌和大肠杆菌具有显著的杀菌作用。

Titanium Surface Modified with Polymeric Quaternary Ammonium Compound by Atrp and Its Antibacterial Properties.

Objective: To evaluate the antibacterial ability of a kind of polymeric quaternary ammonium compound grafted on titanium surface by ATRP. Methods: Titanium surface was grafted with poly(dimethylaminoethyl methacrylate) brush (PDMAEMA) by ATRP and further decorated with 1-bromohexadecane to synthesis polyquaternium. The modified surfaces were characterized using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and attenuated total reflectance Fourier transform infrared (FTIR). The antibacterial performance of the modified surfaces was evaluated with the streptococcus mutans (S.m) and Escherichia coli (E. coli) attachment test by fluorescence microscope and scanning electron microscope. Results: Contact angle measurements, XPS, and FTIR showed the aimed products were successfully deposited on Ti surface. No matter gram-positive S.m or gram-negative E. coli, there were a lot of live bacteria and little dead bacteria on the Ti surface, however, almost full of dead bacteria on the modified Ti surface. Furthermore, modified surface showed great antibacterial ability after 4h and 24h. The results of SEM were the same as that of FM that the bacteria on modified surface were much less than bare titanium. Conclusion: A kind of polymeric quaternary ammonium compound was successfully grafted on the titanium surface. And the modified surface possessed great antibacterial ability.