Enhanced Polychromatic Luminescence of Bionic Peptidyl Nanoparticles Driven by Hydrogen Bonds

Abstract

AbstractOwing to their good biocompatibility, flexible structure, and ease of assembling, peptide nanomaterials have become one of the excellent candidates for the construction of fluorescent molecules and attracted much attention in the field of biomedicine. Inspired by green fluorescent protein and its mutants, a series of dipeptide derivatives are designed. The dipeptides aggregate into nanoparticles and bind together by intermolecular forces to produce multicolor fluorescence. Aromatic stacking and hydrogen bond networks may cause the residues on the side chains of dipeptides to form charge transfer configurations with cyclopentadiene in the nanoparticles. In particular, the ferrocene‐phenylalanine histidine (Fc–FH) dipeptide assembly contains abundant hydrogen bonds. Hydrogen atoms in hydrogen bonds can shuttle between donor and acceptor groups, causing changes in electron configuration to reduce bandgap energy, resulting in an obvious redshift of the emission spectrum and effectively extending the fluorescence spectrum to the visible light range. The stable fluorescence of ferrocene‐diphenylalanine, ferrocene‐phenylalanine tyrosine, and Fc–FH dipeptides can be detected in the visible light range and used for cell imaging, which shows great potential applications in the field of bioimaging.