Detecting that goo on your teeth in the morning

Bacterial biofilms form when bacteria adhere to a surface and secrete extracellular polymeric substances, forming an extremely robust protective gelatinous shell around the bacteria under stress. Such biofilms are 1000 times more resistant to antibiotics than free-floating planktonic bacteria. Given sufficient time bacteria biofilms are capable of forming on virtually any surface, including those of a wound bed in health care and inner walls of water pipes in industry. An approach to detect and characterize bacterial biofilms using Polypyrrole (PPy) enhanced flexible biofilm sensors based on organic substrate of Polyethylene terephthalate (PET) is being developed. PPy film as functionalization material on electrodes is applied to enhance the strength of electrochemical signals. Flexible PET substrate will enable sensors to be placed in systems with complex geometries and to be produced in the ultra cost roll-to-roll method. Measurements of electrochemical impedance microscopy (EIS) using the PET flexible biofilm sensors on the development of green fluorescent protein (GFP) modified Pseudomonas aeruginosa biofilm were carried out. The measurements successfully capture the changes of charge transfer resistance and capacitance corresponding to the biofilm maturing stages.