二期翻修术目前是治疗关节假体周围感染的“金标准”，但术后再感染率可达25%。二期翻修术中取出假体、彻底清创、使用抗生素骨水泥虽可有效清除游离菌及生物膜，但不能杀灭躲入正常细胞内的细菌--“胞内菌”，是翻修术的盲区。最近的研究证实，“胞内菌”是导致假体周围感染治疗失败的关键原因！这主要是由于绝大多数抗生素难以有效进入细胞和杀灭“胞内菌”。针对该问题，本研究将利用国际相关领域前沿进展--“有序多级孔氧化硅”技术，研发新型“胞内菌特异性抗感染生物材料”，并验证材料体系在感染翻修术中的抗菌性能。新型材料具有以下优势：1）“胞内菌”特异性：材料颗粒与游离菌靶向结合，并随细菌特异性进入含“胞内菌”的细胞，不进入健康细胞；2）智能控释：材料在细胞外环境不释放抗生素而作为储存抗生素的药库，进入细胞内后才持续、有序释放；3）载药量大：材料颗粒可加载约自身重量5倍的抗生素；4）载药种类多：对药物无热稳定要求。

Periprosthetic joint infection remains one of the leading causes of revision following hip or knee arthroplasty. The two-stage revision procedure is currently the "gold standard" for the treatment of prosthetic joint infections. However, the re-infection rate after two-stage revision has been reported to be as high as 25%. During the two-stage revision procedure, the infected tissues were thoroughly debrided, the prostheses were removed, and the antibiotic-laden bone cement was applied. These operations could effectively remove the planktonic bacteria and their biofilm, but be unable to kill the "intracellular bacteria", which hided in the local cells such as the osteoblasts. The recent studies have confirmed that most of the commonly used antibiotics could not effectively enter into the cells to kill the "intracellular bacteria", and these "intracellular bacteria" are the major cause of infection relapse after the revision surgery. ..Aiming at the above problems, the current research will utilize the international cutting-edge technologies of the related fields – "Mesoporous Materials", to develop a new intelligent biomaterial with the function of "Intracellular bacteria specific and lysosomal enzyme - response controlled release of antibiotic". The new material has the following advantages:Ⅰ) The nanoparticles of the material can selectively connect to the anionic surfaces of planktonic bacterial, and not combine the exterior zwitterionic surfaces of most healthy animal cells. Therefore, along with the planktonic bacteria, the material particles are able to specifically enter into the cells containing the "intracellular bacteria", but does not enter into the normal cells without the "intracellular bacteria"; Ⅱ) The material nanoparticles does not release the antibiotics in the extracellular environment, but serve as storage depot of the antibiotics. After entering the cells, the material starts releasing antibiotics continuously; Ⅲ) The material nanoparticles can be loaded with large volume of antibiotics, and extend the release of antibiotics inside the cell to provide continuous effective antimicrobial activity to thoroughly kill the "intracellular bacteria"; Ⅳ) The material does not require the thermal stability of the antibiotics, which is different from the bone cement, therefore, almost all kinds of antibiotics can be loaded.