▎ 摘　　要

A stable and effective chiral electrochemical sensor was designed to selectively identify tyrosine (Tyr) enantiomers by square wave voltammetry (SWV). Single-layer graphene oxide (SGO) and amino-beta-cyclodextrin (NH2-beta CD) were integrated through an amidation reaction and then assembled with black phosphorus nanosheets (BPNSs) with a puckered orthorhombic layered structure to construct a chiral composite, which was used to modify a glassy carbon electrode to obtain a chiral electrochemical sensor (SGO-NH2-beta CD/BPNSs/GCE). Compared with the previously reported results, the covalent coupling and self-assembly methodologies for the preparation of SGO-NH2-beta CD/ BPNSs/GCE greatly improved its recognition efficiency for Tyr enantiomers. SGO-NH2-beta CD/BPNSs/GCE showed a relatively higher affinity for D-Tyr with a lower oxidation peak potential and a higher oxidation peak current. Due to the different steric hindrances, the selective formation of hydrogen bonds among the hydroxyl/carboxyl groups of SGO-NH2-beta CD/BPNSs and the amino/carboxyl/phenolic hydroxyl groups of D-Tyr derived from the more suitable intermolecular distances, and the P-O interaction between SGO-NH2-beta CD/BPNSs and the phenolic hydroxyl/carboxyl groups of Tyr, better identification efficiency (Delta E-p = E-D - E-L = 36 mV and I-D/I-L = 1.94/Delta I = 8.89 mu A) could be observed. Importantly, the concentrations of Tyr enantiomers had a good linear relationship with the peak currents, and the percentages of D-Tyr in racemic Tyr mixtures could be predicted at SGO-NH2-beta CD/BPNSs/GCE, confirming its ability in detection and quantitative analysis of Tyr enantiomers.