Conductive imprinted polymeric interfacially modified electrochemical sensors based on covalently bonded layer-by-layer assembly of Gr/Au with flower-like morphology for sensitive detection of 2,4,6-TCP.

Abstract

Polymeric membrane sensors based on molecular imprinted polymers (MIPs) have been attractive analytical tools for detecting organic species. However, the MIPs in electrochemical sensors developed so far are usually prepared by in situ polymerization of pre-polymers and non-covalent adsorption on the surface of the working electrode. Meanwhile, the MIPs in the electrochemical sensors developed are typically made of a non-conductive polymer film. This results in a relatively low current due to the lack of electron transfer. Additionally, the smoothness of the traditional electrochemical substrate results in a low specific surface area, which reduces the sensitivity of the electrochemical sensor. Here, we describe a novel electrochemical sensor with a conductive interface and MIPs modification. The electrochemical sensor was modified by covalent coupled layer by layer self-assembly with the imprinted polymer film. The incorporation of these two conductive functional materials improves the conductivity of the electrodes and provides interface support materials to obtain high specific surface area. By using 2,4,6-trichlorophenol as the model, the sensitivity of the developed conductive sensor was greatly improved compared to that of the traditional MIPs sensor. We believe that the proposed MIPs-based sensing strategy provides a general and convenient method for making sensitive and selective electrochemical sensors.