Development of Circularly Polarized Luminescence (CPL) Peptides Containing Pyrenylalanines and 2-Aminoisobutyric Acid

Abstract

Chiral organic and organometallic luminophores that possess circularly polarized luminescence (CPL) properties in the near-ultraviolet to near-infrared region have several useful applications. However, the CPL properties are subject to inherent factors of the compounds; to date, studies on the CPL properties influenced by amino acids and peptides are scarce. Consequently, we developed peptide-pyrene organic luminophores exhibiting various CPL properties. It is conceivable that the peptide-pyrene organic luminophores can be obtained as aggregates when dissolved in a solution. It is also possible that the formation of aggregates makes it difficult to accurately examine the CPL of the peptide in the solution. This study showed that the introduction of sterically hindered 2-aminoisobutyric acid (Aib) units into the peptide backbone inhibits aggregate formation. The resulting luminophores exhibit CPL properties owing to the presence of pyrene units. The results of this study can form a basis for the design of future materials that use peptide-pyrene organic luminophores.

Non-Classical Circularly Polarized Luminescence Control of Peptide Luminophore Based on Precise Chiral Space Control

“…Peptide-Pyrene Organoluminescent Materials [33] The effect of the number of pyrene rings located within a peptide on the chiroptical properties of optically active peptide-pyrene luminescent materials was investigated. Peptide-pyrene luminescent materials (L)-4 to (L)-6 and (D)-4 to (D)-6 were synthesized with fixed distances between the pyrenylalanine units and different numbers of pyrene rings in the peptides: two, four, and six (Figure 7).…”

Special Issue: Advances of Peptide Engineering

“…Mimura et al (Y. Imai lab.) [7] developed peptide-pyrene organic luminophores containing the 2-aminoisobutyric acid (Aib) units. The Aib peptide-pyrene exhibited excimer CPL (circularly polarized luminescence) in organic solvent upon increasing the number of pyrene units.…”