Surface Topographical Engineering of Chiral Au Nanocrystals with Chiral Hot Spots for Plasmon-Enhanced Chiral Discrimination

Abstract

Surface roughness in chiral plasmonic nanostructures generates asymmetrical localized electromagnetic fields, which hold great promise for applications in chiral recognition, chiroptical spectroscopic sensing, and enantioselective photocatalysis. In this study, we develop a surface topographical engineering approach to precisely manipulate the surface structures of chiral Au nanocrystals. Through carefully controlling the amounts of l- or d-cystine (Cys) and the seed solution in the growth process, we successfully synthesize chiral Au nanocrystals with highly disordered, ordered, and less ordered wrinkled surfaces. An underlying principle governing the relationship between surface roughness, orderliness, and chiroptical response is also proposed. More importantly, the chiral ordered wrinkles on the surfaces of the nanocrystals generate asymmetrical localized electronic fields with enhanced intensity, which achieve excellent plasmon-enhanced chiral discrimination ability for penicillamine (Pen) enantiomers. This work offers exciting prospects for manipulating the surface structures of chiral nanocrystals and designing highly sensitive plasmon-enhanced enantioselective sensors with chiral hot spots.

A Liquid–Liquid Interfacial Strategy for Construction of Electroactive Chiral Covalent–Organic Frameworks with the Aim to Enlarge the Testing Scope of Chiral Electroanalysis

“…Given that, it is of great importance to determine the configurations and enantiomeric excess (ee) of chiral molecules. Up to date, different kinds of techniques have been widely employed for enantioselective sensing, including chromatography, − spectroscopy, − and electrochemistry. − Among them, chiral electroanalysis has the advantages of simple operation and high sensitivity, which only needs testing samples to supply electrochemical signals by themselves. The common recognition chiral molecules include dopamine, acids, , and part of amino acids (tryptophan, phenylalanine, and cysteine). − ,, However, it is still difficult to perform chiral discrimination with respect to the molecules in the absence of electroactive units.…”

Fe Single-Atom Carbon Dots Nanozyme Collaborated with Nucleic Acid Exonuclease III-Driven DNA Walker Cascade Amplification Strategy for Circulating Tumor DNA Detection

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Enantiomer-Selective Magnetoresistance in Chiral Gold Nanocrystals by Magnetic Control of Surface Potentials

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