CER Group 1 article published in JoVE Bioengineering The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions Marylène Vandevenne*1, Mathieu Dondelinger*1, Sami Yunus2, Astrid Freischels1, Régine Freischels1, Oscar Crasson1, Noureddine Rhazi1, Pierre Bogaerts3, Moreno Galleni1, Patrice Filée4 1Life Science Department, University of Liège, 2Institute of Condensed Matter and Nanoscience, Catholic University of Louvain, 3Laboratory of Clinical Microbiology, Catholic University of Louvain, 4Biotechnology Department, CER Group In this work, we report a new method to study protein-protein interactions using a conductimetric biosensor based on the hybrid β-lactamase technology. This method relies on release of protons upon hydrolysis of β-lactams.