Magnesium Zinc Oxide Nanostructure-Modified Multifunctional Sensors for Full-Scale Dynamic Monitoring ofPseudomonas aeruginosaBiofilm Formation

We demonstrate magnesium zinc oxide nanostructure (MZO(nano)) modified multifunctional devices for the full-scale dynamic monitoring ofPseudomonas aeruginosa(P. aeruginosa) biofilm formation: the dual-gate thin film transistor (DGTFT) as an electrical sensor for early stage detection and the quartz crystal microbalance (QCM) as an acoustic sensor for long-term monitoring. The sensing surfaces of both devices were modified with MZO(nano)to enhance their sensitivity and biocompatibility.P. aeruginosabacteria were cultured in vitro on both sensing surfaces. The early stage detection is realized by sensing the charge transfer from cell membrane to the MZO(nano)during bacterial adhesion using the DGTFT biosensor while the monitoring of the long-term evolution is achieved through the sensing of mass loading and viscoelastic transition during biofilm development using the MZO(nano)QCM. The drain current of DGTFT starts to change at the beginning of the test and levels off after similar to 6.5 h of bacterial inoculation, whereas the signals of MZO(nano)QCM become detectable after similar to 5 h and then lasts for 24 h. The full-scale process of biofilm development covering from bacterial adhesion to maturation is thus dynamically monitored using this MZO(nano)modified multifunctional sensing technology.