Simple electrochemical detection of Listeria monocytogenes based on a surface-imprinted polymer-modified electrode

Abstract

Listeria monocytogenes (LM) is a foodborne pathogen, and it can pose a risk of serious diseases to the human health. Hence, the development of an effective method for the detection of LM is very important. In this study, by selecting LM as the template and 3-thiopheneacetic acid as the functional monomer, an LM-imprinted polymer (LIP)-based sensor was proposed for the first time to detect LM by electropolymerizing TPA on the glassy carbon electrode (GCE) surface in the presence of LM. After the removal of the LM template from the electrode surface, the obtained sensor was denoted as LIP/GCE, which could effectively recognize and capture LM cells. By using [Fe(CN)₆]^4−/3− as the probe, its peak current at LIP/GCE could be restricted when the LM cells were captured into the imprinted cavity of LIP/GCE, and the current value decreased with an increase in the LM concentration. Serious conditions were optimized for achieving highly sensitive detection, and a low detection limit (6 CFU mL⁻¹) coupled with a wide linear range (10 to 10⁶ CFU mL⁻¹) was obtained for LM. Finally, the inter-electrode reproducibility, stability, selectivity, and applicability of LIP/GCE were also investigated, and the obtained results were acceptable.