π-π作用诱导的胶原纳米纤维分级自组装

Hierarchical self-assembly of collagen nanofibril via π-π interaction

类胶原多肽(collagen-like peptides)具有来源清洁和可调控等优点,是研究胶原蛋白分子的理想模型.本研究将两个含有不同芳香环数量的有机小分子3,3′-二甲基-4,4′-联苯二异氰酸酯和1,4-苯二异氰酸酯修饰在类胶原多肽的氮端,形成杂合肽,利用有机小分子提供的π-π作用力促进其自组装,并研究芳香环数量对胶原三股螺旋进一步高聚的影响.通过原子力显微镜(atomic force microscope,AFM)和透射电子显微镜(transmission electron microscope,TEM)对高聚组装的类胶原杂合肽进行形貌表征.结果表明,经3,3′-二甲基-4,4′-联苯二异氰酸酯分子修饰的类胶原杂合肽可以高聚组装形成纳米纤维结构,其氮端含有两个芳香环,分子空间结构较大,可能实现三股螺旋交错堆叠组装,这为胶原纳米纤维分级自组装提供了一种新思路.

With advantages of clean source and controllability,collagen-like peptides represent a desirable model for collagen molecule research.In this paper,two small organic molecules containing different numbers of aromatic rings,3,3′-dimethyl-4,4′-biphenylene diisocyanate and 1,4-phenyl diisocyanate,were used to modify the N-terminal of the collagen-like peptides and formed hybrid peptides.It was point out that theπ-πinteraction provided by the small organic molecules could promote the self-assembly of these hybrid peptides.The effect of the number of aromatic rings on the high-polymerization of collagen triple helix was studied.The morphology of the aggregation states was characterized with atomic force microscope(AFM)and transmission electron microscope(TEM).The results showed that the collagen-like hybrid peptide modified by 3,3′-dimethyl-4,4′-biphenylene diisocyanate could assemble into nanofibril structures,and its large molecular structure with two aromatic rings at the N-terminal could promote the collagen triple helix staggered stack assembly,which provides a new strategy for the hierarchical self-assembly of collagen nanofibrils.