CCS Chem, 2022, 4, 2816–2828. 

Abstract: Dynamic transitions of supramolecular assemblies between lower-order structures and higher-order superhelical structures (e.g., double-helical DNA, helical biopolymers) are of vital importance in many physiological processes, but still remain a great challenge to be realized in artificially assembled systems. Herein, a novel biphenyl central core symmetrically coupled with phenylalanine groups drives the construction of the dynamic superhelix. The rotary packing of biphenyl central units allows π–π stacking under the molecular aggregation state, which combines with hydrogen bonding between phenylalanine moieties to contribute to the formation of the superhelix. Notably, the coordination between carboxyl moieties and metal ions enables the in situ morphological transition between the superhelix and nanospheres, which is regulated by the redox reaction. The superhelical fibers mimicking the extracellular matrix exhibit stronger stereospecific interactions with proteins than primary fibers, facilitating cell adhesion and proliferation. Moreover, the dynamic superhelical fibers as cell culture scaffolds can induce cell release via change of morphology from superhelix to nanospheres. This study provides an innovative approach to explore the supramolecular assembly-related biological processes by the dynamic variation of the superstructured helix in artificial systems.

https://dx.doi.org/10.31635/ccschem.021.202101284