Self-assembled nanotube via control over polypeptoid helix

Chirality effect plays a crucial role in life science by underpinning the formation of chiral structures across all length scales, which further manifests itself in material properties, but is notoriously difficult to leverage in synthetic systems. Here, bioinspired polypeptoids-poly(N-substituted glycines) incorporating a chiral center on the backbone were designed and synthesized to understand the effect of chirality on self-assembly in bioinspired peptidomimics devoid of hydrogen bonding. As demonstrated in this study, polypeptoid helices display sergeants-and-soldiers behaviour to give chiral amplification. In addition, the rotational strength of polypeptoid helix was tuned by the numbers of chiral centers incorporated on the backbone. Stable helical conformational as examined by electron circular dichroism (ECD) and vibrational circular dichroism (VCD) results in strong inter-chain interactions, giving rise to self-assembled nanotube in good solvent as driven by orientational packing.