OECT-Based Real-Time Monitoring of Biofilms Enabling Online Evaluation of Antibiofilm Agents in Flow Culture

Here, we report a novel organic electrochemical transistor (OECT)-based strategy for the real-time monitoring of biofilms in flow culture. Bacteria commonly form biofilms to survive an unfavorable environment. Protected by their featured extracellular polymeric substances (EPS), biofilm-related diseases are difficult to treat using normal antibacterial treatments like antibiotics. The development of new antibiofilm agents requires real-time monitoring techniques to evaluate the response of biofilms to treatments. The OECT-based platform reported here realized the online investigation of biofilms by utilizing the intrinsic sensitivity of OECTs in non-faradic impedimetric biosensing. It achieved the capability of distinguishing different stages in the biofilm life cycle through an extended-gate design of the OECT device integrated with a microfluidic-based flow culture chip. We further explored using this system as an evaluation platform for novel antibiofilm agent development. The OECT platform successfully identified the unique effectiveness of extracted porcine gastric mucin (PGM) in treating mature biofilms in flow culture, outperforming polymyxin B.