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 glum 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.