Interaction of Single E. coli Bacteria and Phage Revealed and Quantified by Electrochemical Collision Technique

Interactions between phage and bacteria play pivotal roles in many fundamental biological processes and practical sensing and therapy applications, while direct in situ observation of their interaction at the single bacterial level remains a great challenge. Herein, the electrochemical collision technique was used to investigate the phage-bacteria interactions at different stages. Besides using a surface blockage strategy to evaluate the phage-induced change in concentration and morphology of the E. coli, we also found very interesting discrete spikes in the current-time recordings during the bacteria damage and lysis processes, ascribing to the released membrane vesicles with H₂O₂ from the host bacteria. This work not only provides valuable insights into the dynamic and complex interactions between phage and bacteria at a single bacterial level but also can be of great potential useful for various phage-based applications, including therapeutic phage screening, sensitive bacteria detection, and H₂O₂ production.