Voltammetric Determination of Chloramphenicol Based on Glassy Carbon Electrode Modified With 3,6-Diethynyl-9H-Carbazole Electrodeposited Functional Layer

Abstract

In this paper, we present an original approach for the voltammetric determination of the antibiotic chloramphenicol on a glassy carbon electrode modified with carbon nanotubes and an electrodeposited layer based on 3,6-diethynyl-9H-carbazole used as a molecular recognition agent. The analytical signal was detected by the electrochemical reduction current of the analyte using differential pulse voltammetry. The nature of the intermolecular interaction of chloramphenicol and 3,6-diethynyl-9H-carbazole was studied using molecular absorption and fluorescence spectroscopy, as well as high-performance liquid chromatography. A molecular mechanism of interaction between the recognition agent and the analyte based on the N-alkylation of carbazole with chloramphenicol was proposed. An original approach has been developed for the surface modification of a glassy carbon electrode with carbon nanotubes and the electrodeposition of 3,6-diethynyl-9H-carbazole. Under chosen operating conditions the developed approach allows the voltammetric determination of chloramphenicol with a linear range of detectable concentrations between 0.1 and 1000 µM and a detection limit of 0.02 µM, which are comparable in sensitivity to other methods described in the literature. It has been successfully tested on both model solutions and real samples of milk.