种植体表面液相沉积法构建聚多巴@氯己定抗菌涂层

Antibacterial coating of polyDopa@Chlorhexidine constructed by liquid deposition on implant surface

目的为了预防种植体周围因细菌感染导致的种植失败问题,在纯钛表面液相沉积聚多巴后接枝氯己定形成聚多巴@氯己定涂层(pDA@CHX)来实现纯钛表面的抗菌化处理。方法采用液相沉积法将纯钛浸泡在多巴Tris碱性缓冲溶液中,在纯钛表面沉积聚多巴涂层,然后再次浸泡于氯己定水溶液中,在聚多巴涂层上接枝氯己定,得到pDA@CHX涂层。扫描电镜(SEM)观察涂层的表面形貌;X射线电子能谱(XPS)表征了涂层表面元素组成;水接触角(WCA)检测了涂层的亲水性能;抑菌环(ZOI)和平板涂布实验对涂层的抗菌性能进行了探究;细胞实验采用荧光染色法检验了涂层的生物相容性。结果扫描电镜下与纯钛表面相比构建涂层后纯钛表面分散了很多颗粒状物质;XPS结果显示纯钛表面聚多巴涂层的构建以及氯己定的成功接枝;水接触角实验结果显示聚多巴涂层改善了纯钛表面的亲水性能,在接枝氯己定后,由于氯己定的疏水性样品表面的亲水性降低了,与XPS的结果相符合。抑菌环实验可见在接枝氯己定后可形成直径14 mm左右的抑菌环;平板涂布实验同样证实了在接枝氯己定后涂层具有良好的抗菌性能。体外细胞实验结果显示该涂层具有良好的生物相容性。结论研究结果表明,pDA@CHX涂层在拥有较强的抗菌能力的同时仍然能保持良好的生物相容性,为提高种植体植入成功率提供了新的策略。

Objective Peri-implant bacterial infection contributed to a number of implant failure cases.In this work,a specific antibacterial coating of polyDopa@Chlorhexidine was constructed by liquid deposition on titanium surface.Methods The pure titanium discs was immersed in Dopa Tris alkaline buffer solution by liquid phase deposition method,and the polyDopa coating was deposited on the surface,then polyDopa modified titanium discs were immersed in chlorhexidine solution to covalently immobilized with chlorhexidine.The surface properties were evaluated by scanning electron microscopy,X-ray electron spectroscopy and water contact angle.Antibacterial activity was assessed by plate counting method and inhibition zone method.Biocompatibility was evaluated by fluorescence staining.Results After chlorhexidine grafting,granular substance dispersed on the titanium surface appeared,while the atom ratio of C,N,Cl and the water contact angle increased.A transparent inhibition zone(the diameter of 14 mm)could be observed,which was consistent with the results of plate counting,demonstrating that the modified surface could suppress bacteria multiplication from surrounding environment.When incubating for 1 and 3 days,the cell viability exhibited no significant difference between chlorhexidine groups and control group.Conclusion pDA@CHX coating displayed an exceptional antibacterial activity while possessing an admirable biocompatibility,providing a new strategy for improving the implantation success.