Self-Assembly of Earth-Abundant Supraparticles with Chiral Interstices for Enantioselective Photocatalysis

Abstract

Chiral nanostructures have been extensively studied for bioanalysis and optoelectronics because of their high rotatory optical activity but not for enantioselective catalysis because of the chirality mismatch of geometric scales. Here, we investigate whether the catalytic activity of supraparticles (SPs) made from ZnS NPs could provide a general pathway to reconcile the difficulties. SPs synthesized by two different pathways could enantioselectively oxidize tyrosine (Tyr). Upon illumination with 300–450 nm photons, SPs could convert Tyr into the catechol derivative dihydroxyphenylalanine (DOPA) and Tyr–Tyr dimers coupled via a C–C bond. The enantiomeric preference of substrate conversion is 23–26%, which is an order of magnitude greater than that with metalorganic compounds for the comparable catalytic process in organic solvents. Chiral catalysis substantiated by a photocatalytic oxidation of tryptophan (Trp) could predominantly lead to catechol derivatives with similar enantiomeric preference of 21–25%. This study opens the door to enantioselective catalysts for aqueous mediums taking advantage of the catalytic, photonic, and self-assembly properties of chiral NPs.

Unique Chiro-optical Properties of the Weakly-2D (R-/S-MBA)2CuBr4 Hybrid Material

“…Many chiral materials exist in nature, ranging from small amino acids to macromolecular proteins and macroscopic crystals. Due to a lack of inversion symmetry, chiral materials exhibit various interesting physical properties such as circular dichroism (CD), circularly polarized photoluminescence (CPL), nonlinear optical (NLO) effects, ferroelectricity, bulk photovoltaic effects (BPVE), and the ability to rotate the polarization plane of light. , Chiral organic molecules are abundantly available; however, these generally have very large bandgaps, thereby exhibiting chiro-optical activities in the UV region . In addition, the structural softness of such organic molecules makes it difficult to stack them suitably, and this inability often results in a poor charge transport capability in optoelectronic devices made from such molecules.…”

Peroxidase-Mimicking Hierarchically Organized Gold Particles for Glucose Detection

“…So far, many reports have explored the synthesis of HOPs . HOPs have good dispersion, stability, , bionic behavior, and optical properties. , In this study, we first constructed gold–thiolate hierarchically organized particles (Au HOPs) using cysteine as the surface ligand, which were then reduced using sodium borohydride (NaBH 4 ). Au HOPs-X with different degrees of reduction were synthesized (where X is the concentration of NaBH 4 used, 2, 4, 6, 8, and 10 mM).…”

Planar Chirality for Acid/Base Responsive Macrocyclic Pillararenes Induced by Amino Acid Derivatives: Molecular Dynamics Simulations and Machine Learning

“…Chirality, a fundamental feature of organisms and living systems, has been infiltrated into various research areas, such as chemistry, biochemistry, medicine, and materials . Much effort has been devoted to controlling chirality due to the increasing importance in the fields of chiral recognition/sensing, enantioselective catalysis, and chiral optoelectronics . The enantiomers often exhibit different physiological behaviors or different pharmacological activities. , Most biomolecules exhibit a stereoselective preference for specific biochemical interactions. , The understanding of chirality in nanostructures, such as mesoporous silica, carbon nanotubes, and quantum dots, facilitates the fabrication of well-ordered nanostructures in chiral nanotechnology .…”