Derivative chiral copper(Ⅱ) complexes as template of an electrochemical molecular imprinting sol-gel sensor for enantiorecognition of aspartic acid

Abstract

In this work, we reported a novel electrochemical sensor for enantiorecognition of electrochemically inactive aspartic acid (Asp) enantiomers. By combining sol-gel processing with molecular imprinting technology, an enantioselective interface of molecularly imprinted sol-gel (MIS) films with imprinted cavities was prepared on the surface of a glassy carbon electrode (GCE). In order to obtain the electrochemical responses of electrochemically inactive Asp, the ternary derivative of L-aspartic, (l-aspartic acid)Cu2+(N-carbobenzoxy-l-aspartic acid), was used as the template for fabrication of MIS. The stripping currents of target molecules could be detected by square-wave stripping voltammetry due to the reduction of cupric ion on the modified electrode. The resulted sensor showed good adsorbability to L-Asp derivative, and the recognition efficiency was obtained as 2.1. Meanwhile, the L-Asp was quantitatively determined by the MIS sensor. As a result, the proposed electrochemical sensor could be regarded as a potential platform for enantiorecognition of electrochemically inactive chiral compounds.