Development of a novel electrochemical inhibition sensor array based on bacteria immobilized on modified screen-printed gold electrodes for water pollution detection

The development of a novel and simple inhibition biosensor array for detection of water pollutants based on bacteria immobilized on the surface of the electrodes is the main goal of this work. A series of electrochemical measurements (i.e., cyclic voltammograms) were carried out on modified screen-printed gold electrodes with three types of bacteria, namely Escherichia coli, Shewanella oneidensis, and Methylococcus capsulatus (Bath), immobilized via poly l-lysine. For comparison purposes, similar measurements were carried out on bacteria samples in solutions; also optical measurements (fluorescence microscopy, optical density, and flow cytometry) were performed on the same bacteria in both liquid and immobilized forms. The study of the effect of heavy metal ions (lead), pesticides (atrazine), and petrochemicals (hexane) on DC electrochemical characteristics of immobilized bacteria revealed a possibility of pattern recognition of the above inhibition agents in an aquatic environment.