Ingenious construction of an electrochemical aptasensor based on a Au@COF/GO-NH2 composite with excellent detection performance

Abstract

A great deal of attention has been devoted to the design and synthesis of novel hybrid materials because of their superior performance in far-ranging applications. For the first time, an Au nanoparticle (NP)@covalent organic framework (COF)/amine-functionalized graphene oxide (GO-NH₂) composite (Au@COF/GO-NH₂) has been fabricated, which served as a functional material to modify the electrode surface and load aptamers for fabricating an electrochemical aptasensor. Chloramphenicol (CAP) is selected as an analyte to explore the electrochemical detectability of this aptasensor, which is able to quantificationally detect ultra-trace CAP from 0.0001 to 1 ng mL⁻¹via electrochemical impedance spectroscopy with a limit of detection (LOD) of 16.13 fg mL⁻¹ (49.91 fM). Moroever, this aptasensor exhibits high selectivity, good reproducibility, and fine long-term stability. This study can provide an effective approach to prepare novel composites and expand their potential applications in electrochemical detection.