title: An integrated dielectrophoretic quartz crystal microbalance (DEP-QCM) device for rapid biosensing applications.
abstract: A factor limiting the detection time of biological particles using a quartz crystal microbalance (QCM) system is the kinetics of the particles arriving within the sensing region of the crystal surface. A device has been developed which, for the first time, combines ac electro-kinetic particle manipulation with simultaneous acoustic sensing on an electrode surface. We have termed this device a dielectrophoretic quartz crystal microbalance (DEP-QCM). Particles within the system are rapidly driven by electro-hydrodynamic and dielectrophoretic forces on to the crystal surface. Frequency shift analysis of mass-loaded DEP-QCM, induced by fluid motion, has shown significant improvements in rates of detection based on particle concentration, with steady-state responses established by a factor of five times faster than other quartz crystal microbalance surface loading techniques described in the literature. Comparisons of the static fluid case for QCM devices revealed that particles with a concentration of less than 10(8) nano-spheres/ml could not be detected within a 1h time period when allowed to sediment.
authors.affiliation: Centre for Biomedical Engineering, School of Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK.
authors.forename: Henry O
authors.initials: HO
authors.lastname: Fatoyinbo
authors.forename: Kai F
authors.initials: KF
authors.lastname: Hoettges
authors.forename: Subrayal M
authors.initials: SM
authors.lastname: Reddy
authors.forename: Michael P
authors.initials: MP
authors.lastname: Hughes
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D003199:Computer Systems; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004586:Electrophoresis / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D011791:Quartz; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018511:Systems Integration; D014159:Transducers
chemical_list: D011791:Quartz