胶原蛋白在LB膜上的吸附行为研究

基底的性质和制备方法对吸附胶原层的超分子自组装过程有很大的影响,将一种Gemini表面活性剂C18H37(CH3)2N+-(CH2)12-N+(CH3)2C18H37·2Br-(简写为18-12-18)利用LB技术在零压下转移到云母片上制成基底,浸入到pH值为3.0的胶原溶液中37℃恒温吸附不同的时间,样品用原子力显微镜(AFM)进行表征。结果表明:在恒温过程中,LB膜上的表面活性剂分子会发生移动和翻转,胶原分子优先吸附在LB膜上形成单层网状结构,随吸附时间的延长,胶原分子也会在云母上发生吸附,最后两者会交织成无序的胶原纤维。

Study of the adsorption of type I collagen on LB film

The supra-molecular organization of the adsorbed collagen layer depends on the properties of the substrate surface and the preparation procedure.Langmuir-Blodgett(LB) film of dodecanediyl-bis(dimethyl octadecyl ammonium bromide),a Gemini surfactant,transferred onto mica at zero surface pressure was utilized as the substrate,which was incubated into the solution in the presence of type I collagen at pH3.0 and 37 ℃.The morphologies of these samples were characterized by atomic force microscopy(AFM).After a given adsorption time,the movement and the turnover of some surfactant molecules in the monolayer led to exposure of the part of mica substrates to the collagen solution.The adsorbed collagen could readily and rapidly combine and form the network structure in the region of the monomolecular film,while it might gradually evolve into the network structure in the region of the relatively blank substrate with increasing adsorption time.Finally,both of them could come to be disordered intertwining collagen fibrils.