The Biological Memory Effect in Microbial Fuel Cell Biosensors After Repeated Exposure to Tetracycline

This study investigates the biological memory effect (BME) in microbial fuel cell (MFC) biosensors using tetracycline as a toxic pollutant, aiming to confirm the BME in MFC biosensors. The MFC biosensor is constructed using Ti/Pt thin films and cation exchange membranes, with natural river sediment and raw river water as the inoculum. The experimental design involves three consecutive injections of 10 mg/L tetracycline to observe the BME phenomenon. The current inhibition percentage (CIP) decreases from 77.6% during the first injection to 33.1% and 21.6% during the second and third injections, respectively, which demonstrates the BME in MFC biosensors responding to tetracycline. A kinetic model is developed to describe the interactions between tetracycline and the microbes in the MFC biosensor, and the model is validated with experimental data. This work confirms the BME in MFC biosensors and the kinetic model provides a theoretical foundation for further analysis and optimization of MFC biosensors.