Quartz Tuning Fork as in-situ Sensor of Bacterial Biofilm

Piezoelectric Quartz Tuning Forks (QTFs) were used as a biofilm formation sensors. Modulated excitation technique allowed to measure the current generated by the QTF during the ringdown of the oscillations at conductive environments such as a liquid culture growth medium. New algorithm of the digital analysis of the ring-down signal was elaborated and used to determine the decay time constant of the vibrations and the damped vibration frequency. The dependence of these parameters on the time for QTF placed in liquid growth medium contained four strains of Pseudomonas aeruginosa was measured. It allowed to detect the biofilm formation at the QTF after few hours of incubation for all used strains (2 hours for PA01 strain).