Chirality-Dependent Copper–Diphenylalanine Assemblies with Tough Layered Structure and Enhanced Catalytic Performance

Abstract

Chiral regulation to prepare functional materials has aroused considerable interest in recent years. However, little is known on the effect of chirality of ligands in the metal–organic coordination assembly process. We report the self-assembly of diphenylalanine peptide (Phe-Phe, FF), the core fragment of Aβ protein, with metal copper ion (Cu2+) into metal–organic assemblies with chirality-encoded structures and properties. The chirality-dependent metal–dipeptide assembles with different morphologies and supramolecular chirality were obtained by facile changing of the FF chirality. Single-crystal results indicate that (L)-FF coordinated with Cu2+ into a cross-chain structure with a five-coordinated style, while the racemates of (L+D)-FF with Cu2+ crystallized into an (L)-Cu2+-(D)-Cu2+ alternated four-coordinating structure, enabling a higher mechanical and catalytic performance. The Young’s modulus of (L+D)-FF-Cu is as high as 34.36 GPa, which is 2.45 times higher than that of (L)-FF-Cu. Furthermore, both of them follow the characteristic enzyme kinetics and show higher catalytic activity than natural laccase at the same mass concentration. Specifically, the calculated catalytic efficiency (k cat/K M) of (L+D)-FF-Cu is 1.14 times higher than that of (L)-FF-Cu, and the (L+D)-FF-Cu shows significantly enhanced stability and reusability compared with (L)-FF-Cu. The results reveal that highly functional materials could be constructed by encoding the chirality of molecular building blocks.

Supramolecular chiral polymeric aggregates: Construction and applications

“…[31] In recent years, the supramolecular assembly strategy has become one of the effective ways to design and synthesize novel chiral nanomaterials with special structures and excellent properties. [32][33][34][35][36][37] According to whether chiral units are involved in the supramolecular assembly process, the construction methods of supramolecular chiral assemblies can be roughly divided into the following types: (1) "chiral + chiral" means that only chiral units are used to form ordered supramolecular structure, always exhibiting novel chiral properties beyond a single chiral molecule; [40,41] (2) "chiral + achiral" means that achiral units and chiral units are co-assembled to induce achiral assembly units to show chiral signals in a chiral environment; (3) "achiral + achiral" means complete assembly by achiral units through spontaneous symmetry breakage, leading to exhibiting chirality through their own structural characteristics. [42] Usually, there are two typical amplification effects of chiral induction, namely "Sergeants-and-Soldiers Principle" and "Majority-Rules".…”

“…[ 31 ] In recent years, the supramolecular assembly strategy has become one of the effective ways to design and synthesize novel chiral nanomaterials with special structures and excellent properties. [ 32–37 ]…”

“…Reproduced with permission. [ 37 ] Copyright 2022, American Chemical Society. (C) Scanning electron microscopy images of gold thiolate hierarchically organized particles with different chiral cysteine surface ligands.…”

Coordination-Induced Self-Assembly of a Dipeptide into Multifunctional Chiral Nanostructures

“…The coordination of amino acid residues in peptide chains with metal ions is very common in living organisms, for example, in metalloproteins and metalloenzymes, which perform very important functions in nature, including the storage and transport of oxygen and the transfer and catalysis of electrons. − Inspired by this, peptide-based coordination polymers (CPs), − crystals, and porous metal–organic frameworks (MOFs) − with specific properties have received a lot of attention from researchers in recent years . For example, Ma et al reported flexible peptide-based CPs, that is, Cu­(GT)·2H 2 O, whose crystal structure can be regulated by the breakage and reformation of coordinate bonds .…”

Circularly polarized luminescent organogels based on fluorescence resonance energy transfer in an achiral polymer system

“…[1][2][3] Many chirality-related studies have been intensively carried out to investigate the origin of chirality and fabricate chiral functional materials. [4][5][6][7] Chirality information can be divided into different absorption (ground state) and emission (excited state) of left (L)and right (R)-handed circularly polarized light, respectively. 8 Accordingly, exploring circularly polarized luminescence (CPL) not only facilitates understanding of the nature of chirality in the excited state but also helps us to develop novel chiroptical materials.…”