Self-Assembly of Peptide Hierarchical Helical Arrays with Sequence-Encoded Circularly Polarized Luminescence

Self-assembled peptide materials with sequence-encoded properties have attracted great interest. Despite their intrinsic chirality, the generation of circularly polarized luminescence (CPL) based on the self-assembly of simple peptides has been rarely reported. Here, we report the self-assembly of peptides into hierarchical helical arrays (HHAs) with controlled supramolecular handedness. The HHAs can emit full-color CPL signals after the incorporation of various achiral fluorescent molecules, and the g(lum) value is 40 times higher than that of the CPL signal from the solutions. By simply changing the amino acid sequence of the peptides, CPL signals with opposite handedness can be generated within the HHAs. The peptide HHAs can provide hydrophobic pockets to accommodate the fluorescent molecules with helical arrangement through strong aromatic stacking interactions, which are responsible for the CPL signals. This work provides a pathway to construct highly ordered chiral materials, which have broad applications in the chiroptical field.

Automated summary

This study reports the self-assembly of peptides into hierarchical helical arrays capable of emitting circularly polarized luminescence (CPL), with the handedness of the CPL signals controlled by changing the amino acid sequence. The peptide HHAs provide hydrophobic pockets for accommodating fluorescent molecules with helical arrangement, leading to the generation of CPL signals with high g(lum) values. This work paves the way for constructing highly ordered chiral materials with potential applications in the chiroptical field.