Ultrasonic deposition of cells on a surface.
Bacteria in water have been driven to a glass surface by an ultrasonic standing wave. On an antibody coated surface capture of Bacillus subtilis var niger (BG) spores (6.6 x 10(6) ml(-1)) was increased more than 200-fold over above the efficiency in the absence of ultrasound. In microfluidic (non-turbulent) systems detection of particles by sensors operating at a surface is diffusion limited. This results in very low detection abilities particularly for particles with diameters greater than 1 microm. Ultrasound is used here to drive bacterial spores to a wall and overcome this limitation. The results confirm: (1) pressure nodes can be formed close to the water-glass interface when the glass thickness is near half the ultrasonic wavelength; (2) the antibody used was able to capture spores in the presence of an ultrasonic standing wave.
Hawkes
Jeremy J
JJ
Department of Instrumentation and Analytical Science, UMIST, P.O. Box 88, Manchester M60 1QD, UK. j.hawkes@umist.ac.uk
Long
Michael J
MJ
Coakley
W Terence
WT
McDonnell
Martin B
MB
D001412:Bacillus subtilis; D001422:Bacterial Adhesion; D005898:Glass; D013171:Spores, Bacterial; D014465:Ultrasonics