*Article* **Newly Developed System for the Robust Detection of** *Listeria monocytogenes* **Based on a Bioelectric Cell Biosensor**

**Agni Hadjilouka 1,2,\*, Konstantinos Loizou 1, Theofylaktos Apostolou 1, Lazaros Dougiakis 1, Antonios Inglezakis 1 and Dimitrios Tsaltas 2**


Received: 12 October 2020; Accepted: 14 November 2020; Published: 17 November 2020

**Abstract:** Human food-borne diseases caused by pathogenic bacteria have been significantly increased in the last few decades causing numerous deaths worldwide. The standard analyses used for their detection have significant limitations regarding cost, special facilities and equipment, highly trained sta ff, and a long procedural time that can be crucial for foodborne pathogens with high hospitalization and mortality rates, such as *Listeria monocytogenes*. This study aimed to develop a biosensor that could detect *L. monocytogenes*rapidly and robustly. For this purpose, a cell-based biosensor technology based on the Bioelectric Recognition Assay (BERA) and a portable device developed by EMBIO Diagnostics, called B.EL.D (Bio Electric Diagnostics), were used. Membrane engineering was performed by electroinsertion of *Listeria monocytogenes* homologous antibodies into the membrane of African green monkey kidney (Vero) cells. The newly developed biosensor was able to detect the pathogen's presence rapidly (3 min) at concentrations as low as 10<sup>2</sup> CFU mL−1, demonstrating a higher sensitivity than most existing biosensor-based methods. In addition, lack of cross-reactivity with other *Listeria* species, as well as with *Escherichia coli,* was shown, thus, indicating biosensor's significant specificity against *L. monocytogenes*.

**Keywords:** *Listeria monocytogenes*; cell-based biosensor; bioelectric recognition assay; membrane-engineering
