title: Detection of Pseudomonas aeruginosa using a wireless magnetoelastic sensing device.
abstract: This paper describes the real-time quantification of Pseudomonas aeruginosa (P. aeru) concentrations using a wireless magnetoelastic sensing device. The sensor is fabricated by coating a magnetoelastic ribbon with a polyurethane protecting film. In response to an externally applied time varying magnetic field, the magnetoelastic sensor vibrates at a resonance frequency that can be remotely determined by monitoring the magnetic flux emitted by the sensor. The resonance frequency changes in response to properties changes of a liquid culture medium and bacteria adhesion to the sensor as P. aeru consumes nutrients from the culture medium in growth and reproduction. The effects of properties (conductivity, viscosity, mass) are investigated with quartz crystal microbalance (QCM), microscopy imaging, and conductivity measurement. Using the described technique we are able to directly quantify P. aeru concentrations of 10(3) to 10(8)cells/ml, with a detection limit of 10(3)cells/ml at a noise level of approximately 20 Hz. The lack of any physical connections between the sensor and the monitoring electronics facilitates aseptic operation, and makes the sensor platform ideally suited for monitoring bacteria from within, for example, sealed food containers.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, Department of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, PR China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Pang
authors.forename: Sijing
authors.initials: S
authors.lastname: Huang
authors.forename: Qingyun
authors.initials: Q
authors.lastname: Cai
authors.forename: Shouzhuo
authors.initials: S
authors.lastname: Yao
authors.forename: Kefeng
authors.initials: K
authors.lastname: Zeng
authors.forename: Craig A
authors.initials: CA
authors.lastname: Grimes
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D015169:Colony Count, Microbial / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008280:Magnetics / Q000295:instrumentation*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013686:Telemetry / Q000295:instrumentation*; D014159:Transducers