Shanghai Key Laboratory of Advanced Polymeric Materials, Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Angew Chem Int Ed Engl. 2020 Aug 17;59(34):14281-14285. doi: 10.1002/anie.202004102. Epub 2020 Jul 1.
Toroids and helices are fundamental geometrical structures in nature. Polymers can self-assemble into various nanostructures, including both toroids and helices; however, nanostructures combining toroidal and helical morphologies (that is, helical toroids) are rarely observed. A binary system is reported containing polypeptide homopolymer and its block copolymer, which can hierarchically self-assemble into uniform helical nanotoroids in solution. The formation of the helical toroids is a successive two-step process. First, the homopolymers aggregate into fibrils and convolve into toroids, thereby resembling the toroidal condensation of deoxyribonucleic acid (DNA) chains. Second, the block copolymers self-assemble on the homopolymer toroids and result in helical surface patterns. Additionally, the chirality of the surface helical patterns can be varied by the chirality of the polypeptide block copolymers.
环和螺旋是自然界中的基本几何结构。聚合物可以自组装成各种纳米结构，包括环和螺旋；然而，很少观察到同时具有环和螺旋形态的纳米结构（即螺旋环）。本文报道了一种包含多肽均聚物及其嵌段共聚物的二元体系，该体系可以在溶液中分级自组装成均匀的螺旋纳米环。螺旋环的形成是一个连续的两步过程。首先，均聚物聚集形成原纤维并卷曲成环，类似于脱氧核糖核酸（DNA）链的环凝聚。其次，嵌段共聚物在均聚物环上自组装，形成螺旋表面图案。此外，通过多肽嵌段共聚物的手性可以改变表面螺旋图案的手性。
