摘要

Alfa-cyclodextrin (alpha-CD) based chiral sensing device is proposed for electrochemical recognition of tyrosine (Tyr) isomers. alpha-CD was first modified with Cu2+, and then the obtained Cu2+-modified alpha-CD (Cu-2-alpha-CD) was integrated to chitosan (CS) to form a coordination-driven self-assembly. The amino group and phenolic hydroxyl group of Tyr could form three intermolecular H-bonds with the high-energy water molecules confined in the cavity of Cu-2-alpha-CD. The host (self-assembly)-guest (Tyr isomers) interactions are different for D- and L-Tyr due to the opposite steric configurations of the Tyr isomers, resulting in significantly discernable electrochemical differences in both peak currents and peak potentials and consequently effective chiral recognition of Tyr isomers. The temperature-sensitivity and chiral specificity of the proposed self-assembly are also investigated in this work. Finally, the percentage of D-Tyr in a racemic mixture can be accurately predicted with the CS/Cu-2-alpha-CD self-assembly, showing its potential in practical applications.