Research On Chiral Recognition Performance Of Gold Nanorods And Gold Nanocubes

Chirality exists widely in the nature.Many substances in the bio-organism are chiral and the life activities involved in chiral substances often belong to chiral recognition.Therefore,chiral recognition is of great significance.In this paper,gold nanorods and gold nanocubes unmodified with chiral reagents were synthesized.Then their chirality and chiral recognition performance were explored systematically.A simple,fast and low-cost method for the identification of enantiomers was established.1.Research on the chiral recognition performance of gold nanorodsGold nanorods are gold nanoparticles with rod-like structure.Gold nanorods with different aspect ratios will show some differences in optical properties,catalytic properties and biological applications.In this study,we synthesized three kinds of AuNRs with different aspect ratios which coated with CTAB.First,the chirality of gold nanorods with different aspect ratios was systematically studied by circular dichroism spectroscopy.The experimental results show that the chirality of gold nanorods has a significant dependence on the aspect ratio.That is the chirality of gold nanorods increases with the increase of the aspect ratio.In addition,the chiral recognition ability of AuNRs with different aspect ratio for 19 kinds of a-amino acids was studied in detail.Finally,the AuNRs with the aspect ratio of 4.8 were used as colorimetric probes to quantitatively detect the enantiomers of valine,and the mechanism of chiral recognition was investigated through a series of verification experiments.This work studied the main factors affecting the chirality of gold nanorods and established a simple and sensitive new method of chiral analysis.2.Chiral recognition of a-amino acids using gold nanocubes as colorimetric probesGold nanoparticles with different morphologies show different degrees of difference in optical properties,catalytic properties,and surface-enhanced Raman effects.In this paper,we synthesized CTAB-coated gold nanocubes and measured its circular dichroism spectrumin in this experiment.The results show that the AuNCs are chiral.Since CTAB on the surface of AuNCs is a achiral reagent,we believe that the chirality of gold nanocubes is its intrinsic chirality.Using the AuNCs as chiral recognition probe,the results show that AuNCs have a recognition function for some amino acids.In this paper,the AuNCs were used as colorimetric probes to quantitatively detect the enantiomers of leucine,and the mechanism of chiral recognition was investigated through a series of verification experiments.The experimental results show that AuNCs are a very promising chiral recognition probe.This method based on the inherent chirality of AuNCs is simple,fast and low cost,which provides a new direction for the identification and detection of other chiral enantiomers.