**4. Conclusions**

The present study demonstrates a rapid, high throughput, and portable screening system for *L. monocytogenes* detection, based on membrane-engineered cells. The newly developed biosensor system is combined with a sophisticated algorithm embedded in user-friendly software that allows the end-user to be instantly informed of the analysis results. The aim of this study was the proof-of-concept of the biosensor system for *L. monocytogenes* detection and the optimization of parameters that affect its performance, such as the type and the concentration of the electroinserted antibody. The newly developed biosensor was proven to be a robust and selective tool for *L. monocytogenes* detection, with a limit of detection as low as 10<sup>2</sup> CFU mL−1. Therefore, in future research, the essay will be optimized in different food substrates and validation of its ability to detect pathogen's presence on actual food samples will be performed, identifying and eradicating potential impediments due to the matrix effect.

**Author Contributions:** Conceptualization, D.T. and K.L.; Data curation, A.H., T.A., L.D., K.L. and A.I.; Investigation, A.H. and T.A.; Methodology, A.H., T.A. and K.L; Supervision, D.T.; Validation, A.H. and T.A.; Visualization, K.L.; Writing—original draft, A.H. and T.A.; Writing—review and editing, D.T. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by RESTART 2016–2020 Programmes for Research, Technological Development and Innovation of the Research and Innovation Foundation (RIF) in Cyprus. (project "Post-Doc/0718/0003", Post Doctoral Researchers Programme).

**Conflicts of Interest:** The authors declare no conflict of interest.
